• Re: William T. Parry gets rid of Disjunction introduction

    From Mikko@mikko.levanto@iki.fi to comp.theory,sci.logic,sci.math,comp.ai.philosophy on Sat Jun 27 10:08:10 2026
    From Newsgroup: comp.theory

    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier
    statements by a truth-preserving transformation. Or-intrduction
    discussed above is a truth-preserving transformation.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to comp.theory,sci.logic,sci.math,comp.ai.philosophy on Sat Jun 27 10:11:18 2026
    From Newsgroup: comp.theory

    On 26/06/2026 16:22, dbush wrote:
    On 6/26/2026 9:17 AM, olcott wrote:
    On 6/26/2026 8:14 AM, dbush wrote:
    On 6/26/2026 8:49 AM, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.


    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.


    Given that the following statement is true:

    --------------------------------------
    There is a Walmart bag at the deepest point of the Mariana Trench.
    --------------------------------------

    And the following statement has an unknown truth value:
    --------------------------------------
    There is a Walmart bag at the deepest point of the Mariana Trench.
    --------------------------------------

    When put together in the following natural language sentence:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - There is a Walmart bag at the deepest point of the Mariana Trench.
    --------------------------------------

    Is the condition "At least one of the following statements is true"
    satisfied?


    You either are not bright enough to understand
    the deep meaning of Disjunction introduction or
    you are playing head games. Unless you want an
    honest dialogue please fuck off.

    Why is it a head game?

    Because you are playing Olcott's game.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Ross Finlayson@ross.a.finlayson@gmail.com to comp.theory,sci.logic,sci.math,comp.ai.philosophy on Sat Jun 27 07:18:26 2026
    From Newsgroup: comp.theory

    On 06/26/2026 06:24 AM, dbush wrote:
    On 6/26/2026 9:22 AM, dbush wrote:
    On 6/26/2026 9:17 AM, olcott wrote:
    On 6/26/2026 8:14 AM, dbush wrote:
    On 6/26/2026 8:49 AM, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.


    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.


    Given that the following statement is true:

    --------------------------------------
    There is a Walmart bag at the deepest point of the Mariana Trench.
    --------------------------------------

    And the following statement has an unknown truth value:
    --------------------------------------
    There is a Walmart bag at the deepest point of the Mariana Trench.
    --------------------------------------

    When put together in the following natural language sentence:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - There is a Walmart bag at the deepest point of the Mariana Trench.
    --------------------------------------

    Is the condition "At least one of the following statements is true"
    satisfied?


    You either are not bright enough to understand
    the deep meaning of Disjunction introduction or
    you are playing head games. Unless you want an
    honest dialogue please fuck off.



    Why is it a head game? It's a simple question:

    Is the condition "At least one of the following statements is true"
    satisfied?

    Not answering this question can only be seen as dishonest. Do you
    intend to be dishonest?

    Copy/paste error above: the following statement is given as true:

    --------------------------------------
    Earth is the third planet from the sun. --------------------------------------




    The "conjunctive normal form" (CNF) is a rather simple thing,
    being able to write things in terms of "AND" instead of "OR",
    for things like satisfiability (SAT problems, SAT solvers),
    that in terms of

    AND

    and

    OR

    and sometimes

    XOR

    and not so often

    NOR and XNOR

    with the

    NOT

    being a sort of predicate while then the above are combinators
    and operators, point being CNF while it simplifies some things,
    makes other things impossible, basically limits and completions.


    So, "getting rid of it" as part of the "term-free, constant-free, variable-free, parameter-free", also loses some expressive power,
    so this is also broken open and "PO" will again have to find a
    new one, as Prawitz et alia's "recovery" is an extensions, and
    this Parry's "truncation" is a fragment.

    Nobody needs "eliminating disjunctive introduction" to
    cut out "material implication" and its fiend "principle of explosion",
    it's like saying gonads are dirty and the best solution is to
    have them removed. It's like when people have prostatitis and
    end up getting prostatectomies when they should work it out.




    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From polcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 10:11:15 2026
    From Newsgroup: comp.theory

    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier statements

    Except with Disjunction introduction, that is its problem.

    by a truth-preserving transformation. Or-intrduction
    discussed above is a truth-preserving transformation.


    We know that "Not all lemons are yellow", as it has been assumed to be true.

    We know that "All lemons are yellow", as it has been assumed to be true.

    Therefore, the two-part statement "All lemons are yellow or unicorns exist"

    https://en.wikipedia.org/wiki/Principle_of_explosion

    I don't get why this was not tossed out as a psychotic
    break from reality the first moment that the first
    person thought of the POE. Human minds must be hard
    wired with short-circuits.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 13:54:21 2026
    From Newsgroup: comp.theory

    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a statement X
    such that the condition "At least one of the following statements is
    true" is false.

    Name it.




    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 13:03:01 2026
    From Newsgroup: comp.theory

    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 14:24:12 2026
    From Newsgroup: comp.theory

    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-topic.

    Failure to do so in your next reply or within one hour of your next post
    in this newsgroup will be taken as your official, on-the-record
    admission that Disjunction introduction is valid, and by extension that
    so is the Principle of Explosion.


    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a statement X
    such that the condition "At least one of the following statements is
    true" is false.

    Name it.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 13:29:43 2026
    From Newsgroup: comp.theory

    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier >>>>> statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 14:34:12 2026
    From Newsgroup: comp.theory

    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition, >>>>>>>>> sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier >>>>>> statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-
    topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a contradiction is
    given as true, any statement can be proven as true.

    The principle of explosion is a demonstration of *why* a formal system
    whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 18:30:44 2026
    From Newsgroup: comp.theory

    On 6/27/2026 2:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition, >>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>> other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>> formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier >>>>>>> statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-
    topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a contradiction is given as true, any statement can be proven as true.

    The principle of explosion is a demonstration of *why* a formal system
    whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.


    Given that you still haven't responded to this, I (and others reading
    this) can only conclude that you agree that Disjunction introduction is
    valid, and therefore so is the Principle of Explosion.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 17:40:47 2026
    From Newsgroup: comp.theory

    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition, >>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>> other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>> formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier >>>>>>> statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-
    topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a contradiction is given as true, any statement can be proven as true.

    The principle of explosion is a demonstration of *why* a formal system
    whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 18:52:25 2026
    From Newsgroup: comp.theory

    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more
    earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a contradiction
    is given as true, any statement can be proven as true.

    The principle of explosion is a demonstration of *why* a formal system
    whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of
    non-contradiction goes away as it looses its basis.

    We *want* the principle of explosion because it shows us what can happen
    when we have a system that can prove a contradiction.


    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 18:22:31 2026
    From Newsgroup: comp.theory

    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a contradiction
    is given as true, any statement can be proven as true.

    The principle of explosion is a demonstration of *why* a formal
    system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction.

    We *want* the principle of explosion because it shows us what can happen when we have a system that can prove a contradiction.



    It *is* and actual psychotic break from reality
    to prove any damned thing from a contradiction
    besides ⊥ falsum.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 19:30:53 2026
    From Newsgroup: comp.theory

    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as true.

    The principle of explosion is a demonstration of *why* a formal
    system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction.

    Which you can't do because it's a truth-preserving operation.

    That would also means getting rid of any proof that uses it, which is
    probably most, so most mathematical systems would collapse.


    We *want* the principle of explosion because it shows us what can
    happen when we have a system that can prove a contradiction.



    It *is* and actual psychotic break from reality
    to prove any damned thing from a contradiction
    besides ⊥ falsum.

    In other words, you want to be able to use a system that can prove a contradiction.


    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 18:56:37 2026
    From Newsgroup: comp.theory

    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as true. >>>>>
    The principle of explosion is a demonstration of *why* a formal
    system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction.

    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P // Premise
    2) P // Conjunction elimination
    3) ¬P // Conjunction elimination
    4) P ∨ Q // Disjunction introduction
    5) Q // Disjunctive syllogism https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    P = "The Moon is made from green cheese"
    Q = Donald Trump is the one any only Lord
    and savior Jesus Christ.

    P ∨ Q // Q comes from out of nowhere
    ∴ Q by Disjunctive syllogism
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 21:08:28 2026
    From Newsgroup: comp.theory

    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>
    So you're saying that in the following natural language
    statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as true. >>>>>>
    The principle of explosion is a demonstration of *why* a formal
    system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of >>>>>> explosion is to be able to use a system that has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction.

    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a statement X
    such that the condition "At least one of the following statements is
    true" is false.

    Name it.




    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 20:24:12 2026
    From Newsgroup: comp.theory

    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere >>>>>>>>>>>>>> (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>>> eachstatement either is a premis or follows from one or >>>>>>>>>>>>> more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as true. >>>>>>>
    The principle of explosion is a demonstration of *why* a formal >>>>>>> system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of >>>>>>> explosion is to be able to use a system that has a contradiction. >>>>>>>

    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction.

    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a statement X
    such that the condition "At least one of the following statements is
    true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 21:29:37 2026
    From Newsgroup: comp.theory

    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when >>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>> where eachstatement either is a premis or follows from one >>>>>>>>>>>>>> or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid. >>>>>>>>
    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as >>>>>>>> true.

    The principle of explosion is a demonstration of *why* a formal >>>>>>>> system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle >>>>>>>> of explosion is to be able to use a system that has a
    contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction. >>>>
    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a statement
    X such that the condition "At least one of the following statements is
    true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following
    statements is true" is false?

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 20:40:42 2026
    From Newsgroup: comp.theory

    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>> where eachstatement either is a premis or follows from >>>>>>>>>>>>>>> one or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid. >>>>>>>>>
    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as >>>>>>>>> true.

    The principle of explosion is a demonstration of *why* a formal >>>>>>>>> system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle >>>>>>>>> of explosion is to be able to use a system that has a
    contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction. >>>>>
    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a statement
    X such that the condition "At least one of the following statements
    is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun. --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following statements is true" is false?


    Where X is "What time is it?"
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 21:42:10 2026
    From Newsgroup: comp.theory

    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>>> where eachstatement either is a premis or follows from >>>>>>>>>>>>>>>> one or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid. >>>>>>>>>>
    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as >>>>>>>>>> true.

    The principle of explosion is a demonstration of *why* a
    formal system whose axioms lead to a contradiction is useless. >>>>>>>>>>
    The only reason someone would want to get rid of the principle >>>>>>>>>> of explosion is to be able to use a system that has a
    contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non- >>>>>>>> contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction
    introduction.

    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a
    statement X such that the condition "At least one of the following
    statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following
    statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 20:49:29 2026
    From Newsgroup: comp.theory

    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of the >>>>>>>>>>>>>>>>>>>> many
    systems of analytic implication belonging to its >>>>>>>>>>>>>>>>>>>> ilk) is
    the rejection of the classically valid principle of >>>>>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula ϕ >>>>>>>>>>>>>>>>>>>> to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>>>> where eachstatement either is a premis or follows from >>>>>>>>>>>>>>>>> one or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid. >>>>>>>>>>>
    Through a series of truth preserving operations, when a >>>>>>>>>>> contradiction is given as true, any statement can be proven >>>>>>>>>>> as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>> formal system whose axioms lead to a contradiction is useless. >>>>>>>>>>>
    The only reason someone would want to get rid of the
    principle of explosion is to be able to use a system that has >>>>>>>>>>> a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non- >>>>>>>>> contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction
    introduction.

    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a
    statement X such that the condition "At least one of the following
    statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following
    statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 21:53:28 2026
    From Newsgroup: comp.theory

    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of the >>>>>>>>>>>>>>>>>>>>> many
    systems of analytic implication belonging to its >>>>>>>>>>>>>>>>>>>>> ilk) is
    the rejection of the classically valid principle of >>>>>>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula ϕ >>>>>>>>>>>>>>>>>>>>> to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given that >>>>>>>>>>>>>>>>>>>>> it is
    famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>>>>> where eachstatement either is a premis or follows from >>>>>>>>>>>>>>>>>> one or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid. >>>>>>>>>>>>
    Through a series of truth preserving operations, when a >>>>>>>>>>>> contradiction is given as true, any statement can be proven >>>>>>>>>>>> as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>>> formal system whose axioms lead to a contradiction is useless. >>>>>>>>>>>>
    The only reason someone would want to get rid of the
    principle of explosion is to be able to use a system that >>>>>>>>>>>> has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non- >>>>>>>>>> contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction
    introduction.

    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement: >>>>>>
    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a
    statement X such that the condition "At least one of the following >>>>>> statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following
    statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it can't be
    used in logic. I didn't think I had to make that explicit.

    However, let's go with it anyway because it still illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 22:02:44 2026
    From Newsgroup: comp.theory

    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of >>>>>>>>>>>>>>>>>>>>>> the many
    systems of analytic implication belonging to its >>>>>>>>>>>>>>>>>>>>>> ilk) is
    the rejection of the classically valid principle >>>>>>>>>>>>>>>>>>>>>> of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula >>>>>>>>>>>>>>>>>>>>>> ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given that >>>>>>>>>>>>>>>>>>>>>> it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>>>>>> where eachstatement either is a premis or follows >>>>>>>>>>>>>>>>>>> from one or more earlier
    statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural language >>>>>>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when a >>>>>>>>>>>>> contradiction is given as true, any statement can be proven >>>>>>>>>>>>> as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>>>> formal system whose axioms lead to a contradiction is useless. >>>>>>>>>>>>>
    The only reason someone would want to get rid of the >>>>>>>>>>>>> principle of explosion is to be able to use a system that >>>>>>>>>>>>> has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents >>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non- >>>>>>>>>>> contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction
    introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement: >>>>>>>
    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a
    statement X such that the condition "At least one of the
    following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following
    statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it can't be
    used in logic.  I didn't think I had to make that explicit.

    However, let's go with it anyway because it still illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement, does
    there exist a statement X such that the condition "At least one of the following statements is true" is false?

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 22:23:04 2026
    From Newsgroup: comp.theory

    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of >>>>>>>>>>>>>>>>>>>>>>> the many
    systems of analytic implication belonging to its >>>>>>>>>>>>>>>>>>>>>>> ilk) is
    the rejection of the classically valid principle >>>>>>>>>>>>>>>>>>>>>>> of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula >>>>>>>>>>>>>>>>>>>>>>> ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given that >>>>>>>>>>>>>>>>>>>>>>> it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a premis or >>>>>>>>>>>>>>>>>>>> follows from one or more earlier
    statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when a >>>>>>>>>>>>>> contradiction is given as true, any statement can be >>>>>>>>>>>>>> proven as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>>>>> formal system whose axioms lead to a contradiction is >>>>>>>>>>>>>> useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>> principle of explosion is to be able to use a system that >>>>>>>>>>>>>> has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents >>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of >>>>>>>>>>>> non- contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement: >>>>>>>>
    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a
    statement X such that the condition "At least one of the
    following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following >>>>>> statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it can't be
    used in logic.  I didn't think I had to make that explicit.

    However, let's go with it anyway because it still illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement, does
    there exist a statement X such that the condition "At least one of the following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sat Jun 27 23:34:37 2026
    From Newsgroup: comp.theory

    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of >>>>>>>>>>>>>>>>>>>>>>>> the many
    systems of analytic implication belonging to its >>>>>>>>>>>>>>>>>>>>>>>> ilk) is
    the rejection of the classically valid principle >>>>>>>>>>>>>>>>>>>>>>>> of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given >>>>>>>>>>>>>>>>>>>>>>>> that it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a premis or >>>>>>>>>>>>>>>>>>>>> follows from one or more earlier
    statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when a >>>>>>>>>>>>>>> contradiction is given as true, any statement can be >>>>>>>>>>>>>>> proven as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>>>>>> formal system whose axioms lead to a contradiction is >>>>>>>>>>>>>>> useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>>> principle of explosion is to be able to use a system that >>>>>>>>>>>>>>> has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of >>>>>>>>>>>>> non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>

    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement: >>>>>>>>>
    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a >>>>>>>>> statement X such that the condition "At least one of the
    following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a >>>>>>> statement X such that the condition "At least one of the
    following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it can't
    be used in logic.  I didn't think I had to make that explicit.

    However, let's go with it anyway because it still illustrates the point. >>>
    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement, does
    there exist a statement X such that the condition "At least one of the
    following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a head
    game in your next reply or within one hour of you next post in this
    newsgroup will be taken as your official, on-the-record admission that Disjunction introduction is in fact truth preserving and valid, and
    therefore so is the Principle of Explosion.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Sun Jun 28 12:04:36 2026
    From Newsgroup: comp.theory

    On 27/06/2026 18:11, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier
    statements

    Except with Disjunction introduction, that is its problem.

    by a truth-preserving transformation. Or-intrduction
    discussed above is a truth-preserving transformation.


    We know that "Not all lemons are yellow", as it has been assumed to be
    true.

    We know that "All lemons are yellow", as it has been assumed to be true.

    Therefore, the two-part statement "All lemons are yellow or unicorns exist"

    Can you prove that there are no uniconrns in any world where all lemons
    are yellow and some lemons are not yellow?

    A system with contradictory postulates has no model. Therefore no
    sentence is false in any of its models.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Sun Jun 28 12:13:16 2026
    From Newsgroup: comp.theory

    On 28/06/2026 01:40, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more
    earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a contradiction
    is given as true, any statement can be proven as true.

    The principle of explosion is a demonstration of *why* a formal system
    whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of
    explosion is to be able to use a system that has a contradiction.

    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.

    The principle of explosion does not prevent infallible reasoning.
    It merely provides a simple way to detect and expose some failures
    to reason correctly.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Sun Jun 28 12:18:13 2026
    From Newsgroup: comp.theory

    On 28/06/2026 02:56, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>
    So you're saying that in the following natural language
    statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't make it invalid.

    Through a series of truth preserving operations, when a
    contradiction is given as true, any statement can be proven as true. >>>>>>
    The principle of explosion is a demonstration of *why* a formal
    system whose axioms lead to a contradiction is useless.

    The only reason someone would want to get rid of the principle of >>>>>> explosion is to be able to use a system that has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non-
    contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction introduction.

    Which you can't do because it's a truth-preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    The same without disjunction introduction:

    1) P ∧ ¬P // Premise
    2) (P ∧ ¬P) -> Q // Tautology
    3) Q // Modus ponens
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Sun Jun 28 12:22:11 2026
    From Newsgroup: comp.theory

    On 28/06/2026 04:53, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of >>>>>>>>>>>>>>>>>>>>>> the many
    systems of analytic implication belonging to its >>>>>>>>>>>>>>>>>>>>>> ilk) is
    the rejection of the classically valid principle >>>>>>>>>>>>>>>>>>>>>> of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula >>>>>>>>>>>>>>>>>>>>>> ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given that >>>>>>>>>>>>>>>>>>>>>> it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>>>>>> where eachstatement either is a premis or follows >>>>>>>>>>>>>>>>>>> from one or more earlier
    statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural language >>>>>>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when a >>>>>>>>>>>>> contradiction is given as true, any statement can be proven >>>>>>>>>>>>> as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>>>> formal system whose axioms lead to a contradiction is useless. >>>>>>>>>>>>>
    The only reason someone would want to get rid of the >>>>>>>>>>>>> principle of explosion is to be able to use a system that >>>>>>>>>>>>> has a contradiction.


    My reason to get rid of the principle of explosion
    it to get rid of anything and everything that prevents >>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of non- >>>>>>>>>>> contradiction goes away as it looses its basis.


    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction
    introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language statement: >>>>>>>
    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a
    statement X such that the condition "At least one of the
    following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a
    statement X such that the condition "At least one of the following
    statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.

    You made it. It's up to you to correct it. Or you can interprete
    any non-claim as false or assume a third thruth value.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Sun Jun 28 12:23:19 2026
    From Newsgroup: comp.theory

    On 28/06/2026 06:34, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of >>>>>>>>>>>>>>>>>>>>>>>>> the many
    systems of analytic implication belonging to >>>>>>>>>>>>>>>>>>>>>>>>> its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given >>>>>>>>>>>>>>>>>>>>>>>>> that it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a premis >>>>>>>>>>>>>>>>>>>>>> or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when a >>>>>>>>>>>>>>>> contradiction is given as true, any statement can be >>>>>>>>>>>>>>>> proven as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>>>>>>> formal system whose axioms lead to a contradiction is >>>>>>>>>>>>>>>> useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>>>> principle of explosion is to be able to use a system >>>>>>>>>>>>>>>> that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of >>>>>>>>>>>>>> non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>

    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language
    statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a >>>>>>>>>> statement X such that the condition "At least one of the
    following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a >>>>>>>> statement X such that the condition "At least one of the
    following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it can't
    be used in logic.  I didn't think I had to make that explicit.

    However, let's go with it anyway because it still illustrates the
    point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Of course it is. It is Olcott's game.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Sun Jun 28 12:32:12 2026
    From Newsgroup: comp.theory

    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition, >>>>>>>>> sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier >>>>>> statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-
    topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math on Sun Jun 28 22:17:48 2026
    From Newsgroup: comp.theory

    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition, >>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>> other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>> formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier >>>>>>> statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-
    topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.


    That my proof to the contrary was simply erased
    is dishonest. Relevance logic also gets rid of
    the POE a different way.

    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Sun Jun 28 23:56:13 2026
    From Newsgroup: comp.theory

    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and of >>>>>>>>>>>>>>>>>>>>>>>>> the many
    systems of analytic implication belonging to >>>>>>>>>>>>>>>>>>>>>>>>> its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given >>>>>>>>>>>>>>>>>>>>>>>>> that it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a premis >>>>>>>>>>>>>>>>>>>>>> or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when a >>>>>>>>>>>>>>>> contradiction is given as true, any statement can be >>>>>>>>>>>>>>>> proven as true.

    The principle of explosion is a demonstration of *why* a >>>>>>>>>>>>>>>> formal system whose axioms lead to a contradiction is >>>>>>>>>>>>>>>> useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>>>> principle of explosion is to be able to use a system >>>>>>>>>>>>>>>> that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of >>>>>>>>>>>>>> non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>

    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language
    statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a >>>>>>>>>> statement X such that the condition "At least one of the
    following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a >>>>>>>> statement X such that the condition "At least one of the
    following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it can't
    be used in logic.  I didn't think I had to make that explicit.

    However, let's go with it anyway because it still illustrates the
    point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a head
    game in your next reply or within one hour of you next post in this newsgroup will be taken as your official, on-the-record admission that Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above
    question or explain why it is a head game. Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Sun Jun 28 23:13:14 2026
    From Newsgroup: comp.theory

    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and >>>>>>>>>>>>>>>>>>>>>>>>>> of the many
    systems of analytic implication belonging to >>>>>>>>>>>>>>>>>>>>>>>>>> its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given >>>>>>>>>>>>>>>>>>>>>>>>>> that it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ ∧ >>>>>>>>>>>>>>>>>>>>>>>>>> ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a premis >>>>>>>>>>>>>>>>>>>>>>> or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when a >>>>>>>>>>>>>>>>> contradiction is given as true, any statement can be >>>>>>>>>>>>>>>>> proven as true.

    The principle of explosion is a demonstration of *why* >>>>>>>>>>>>>>>>> a formal system whose axioms lead to a contradiction is >>>>>>>>>>>>>>>>> useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>>>>> principle of explosion is to be able to use a system >>>>>>>>>>>>>>>>> that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of >>>>>>>>>>>>>>> non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>>

    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language >>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a >>>>>>>>>>> statement X such that the condition "At least one of the >>>>>>>>>>> following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist a >>>>>>>>> statement X such that the condition "At least one of the
    following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it can't >>>>> be used in logic.  I didn't think I had to make that explicit.

    However, let's go with it anyway because it still illustrates the
    point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game.  Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL
    --


    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math on Mon Jun 29 12:29:59 2026
    From Newsgroup: comp.theory

    On 29/06/2026 06:17, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more
    earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    That my proof to the contrary was simply erased
    is dishonest.

    No, it is not. To pretend having presented a proof when no proof
    has been presented is dishonest. As is to present false claims
    about a presented proof, or abaut anything.

    The comment
    In any sensible logic every tautology is provable.
    Then the principle of explosion follows.
    is perfectly honest.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Mon Jun 29 08:08:39 2026
    From Newsgroup: comp.theory

    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and >>>>>>>>>>>>>>>>>>>>>>>>>>> of the many
    systems of analytic implication belonging to >>>>>>>>>>>>>>>>>>>>>>>>>>> its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given >>>>>>>>>>>>>>>>>>>>>>>>>>> that it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ >>>>>>>>>>>>>>>>>>>>>>>>>>> ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a premis >>>>>>>>>>>>>>>>>>>>>>>> or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is its >>>>>>>>>>>>>>>>>>>>>>> problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make it >>>>>>>>>>>>>>>>>> invalid.

    Through a series of truth preserving operations, when >>>>>>>>>>>>>>>>>> a contradiction is given as true, any statement can be >>>>>>>>>>>>>>>>>> proven as true.

    The principle of explosion is a demonstration of *why* >>>>>>>>>>>>>>>>>> a formal system whose axioms lead to a contradiction >>>>>>>>>>>>>>>>>> is useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>>>>>> principle of explosion is to be able to use a system >>>>>>>>>>>>>>>>>> that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law of >>>>>>>>>>>>>>>> non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>>>

    You keep failing to pay close enough attention.
    I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving operation. >>>>>>>>>>>>>>
    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING.

    So you're saying that in the following natural language >>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a >>>>>>>>>>>> statement X such that the condition "At least one of the >>>>>>>>>>>> following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist >>>>>>>>>> a statement X such that the condition "At least one of the >>>>>>>>>> following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it
    can't be used in logic.  I didn't think I had to make that explicit. >>>>>>
    However, let's go with it anyway because it still illustrates the >>>>>> point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least
    one of the following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record
    admission that Disjunction introduction is in fact truth preserving
    and valid, and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this
    newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above
    question or explain why it is a head game.  Therefore, as per the
    above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.

    If you want to make up your own system, you need to throw out every that depends on any definition or rule that you changed and prove everything
    *from scratch*.

    As you've demonstrated on countless occasions, you don't even have a
    high school understanding of logic, so this is far beyond your abilities.

    In the system everyone works in, Disjunction introduction is truth
    preserving and valid, and therefore so is the Principle of Explosion, as
    you have just admitted on the record above.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From polcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Mon Jun 29 08:17:44 2026
    From Newsgroup: comp.theory

    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent calculus >>>>>>>>>>>>>>>>>>>>>>>>>>>> for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI (and >>>>>>>>>>>>>>>>>>>>>>>>>>>> of the many
    systems of analytic implication belonging to >>>>>>>>>>>>>>>>>>>>>>>>>>>> its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an >>>>>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication—given >>>>>>>>>>>>>>>>>>>>>>>>>>>> that it is
    famously featured in Lewis’ derivation of an >>>>>>>>>>>>>>>>>>>>>>>>>>>> arbitrary
    formula ψ from a contradiction of the form ϕ >>>>>>>>>>>>>>>>>>>>>>>>>>>> ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is >>>>>>>>>>>>>>>>>>>>>>>> its problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic.


    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make >>>>>>>>>>>>>>>>>>> it invalid.

    Through a series of truth preserving operations, when >>>>>>>>>>>>>>>>>>> a contradiction is given as true, any statement can >>>>>>>>>>>>>>>>>>> be proven as true.

    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>>>>>>> principle of explosion is to be able to use a system >>>>>>>>>>>>>>>>>>> that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law >>>>>>>>>>>>>>>>> of non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>>>>

    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination
    3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction
    5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists a >>>>>>>>>>>>> statement X such that the condition "At least one of the >>>>>>>>>>>>> following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there exist >>>>>>>>>>> a statement X such that the condition "At least one of the >>>>>>>>>>> following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it
    can't be used in logic.  I didn't think I had to make that explicit. >>>>>>>
    However, let's go with it anyway because it still illustrates the >>>>>>> point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true?


    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement, >>>>>> does there exist a statement X such that the condition "At least
    one of the following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record
    admission that Disjunction introduction is in fact truth preserving
    and valid, and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this
    newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above
    question or explain why it is a head game.  Therefore, as per the
    above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.


    The bearing that it has on existing systems is that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    https://en.wikipedia.org/wiki/Relevance_logic
    Does this same sort of thing in that they limit logic
    in a different way. If the conclusion is semantically
    irrelevant to its premises then the conclusion is not
    derived.

    If you want to make up your own system, you need to throw out every that depends on any definition or rule that you changed and prove everything *from scratch*.


    In my system we toss out and reject any and all
    logical inference that is not semantic entailment.

    Good: Bobby cut his hair therefore Bobby has less hair.
    Bad: Bobby cut his hair therefore Bobby filled his gas tank.

    The Prolog way to look at this is that in any system
    when the expression x cannot reach Facts though its
    Rules counts as untrue.

    Prolog goes a step further with its "closed world"
    "negation as failure" assumption that unprovable means false.
    I only say that unprovable means untrue it does not
    mean false.

    As you've demonstrated on countless occasions, you don't even have a
    high school understanding of logic, so this is far beyond your abilities.

    In the system everyone works in, Disjunction introduction is truth preserving and valid, and therefore so is the Principle of Explosion, as
    you have just admitted on the record above.

    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Mon Jun 29 09:23:34 2026
    From Newsgroup: comp.theory

    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many
    systems of analytic implication belonging >>>>>>>>>>>>>>>>>>>>>>>>>>>>> to its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is >>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula. Parry blamed on this principle the >>>>>>>>>>>>>>>>>>>>>>>>>>>>> derivability
    of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is
    famously featured in Lewis’ derivation of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula ψ from a contradiction of the form >>>>>>>>>>>>>>>>>>>>>>>>>>>>> ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is >>>>>>>>>>>>>>>>>>>>>>>>> its problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make >>>>>>>>>>>>>>>>>>>> it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any statement >>>>>>>>>>>>>>>>>>>> can be proven as true.

    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of the >>>>>>>>>>>>>>>>>>>> principle of explosion is to be able to use a system >>>>>>>>>>>>>>>>>>>> that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law >>>>>>>>>>>>>>>>>> of non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>>>>>

    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of Disjunction >>>>>>>>>>>>>>>>> introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination
    4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism
    https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists >>>>>>>>>>>>>> a statement X such that the condition "At least one of the >>>>>>>>>>>>>> following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with
    Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>> exist a statement X such that the condition "At least one of >>>>>>>>>>>> the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>> can't be used in logic.  I didn't think I had to make that
    explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>

    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language statement, >>>>>>> does there exist a statement X such that the condition "At least >>>>>>> one of the following statements is true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in >>>>> this newsgroup will be taken as your official, on-the-record
    admission that Disjunction introduction is in fact truth preserving >>>>> and valid, and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in
    this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the
    above question or explain why it is a head game.  Therefore, as per
    the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting with
    the precondition that a contradiction has been proven, as you have
    admitted above on the record.


    https://en.wikipedia.org/wiki/Relevance_logic
    Does this same sort of thing in that they limit logic
    in a different way. If the conclusion is semantically
    irrelevant to its premises then the conclusion is not
    derived.

    If you want to make up your own system, you need to throw out every
    that depends on any definition or rule that you changed and prove
    everything *from scratch*.


    In my system we toss out and reject any and all
    logical inference that is not semantic entailment.

    Good: Bobby cut his hair therefore Bobby has less hair.
    Bad: Bobby cut his hair therefore Bobby filled his gas tank.

    The Prolog way to look at this is that in any system
    when the expression x cannot reach Facts though its
    Rules counts as untrue.

    Prolog goes a step further with its "closed world"
    "negation as failure" assumption that unprovable means false.
    I only say that unprovable means untrue it does not
    mean false.

    As you've demonstrated on countless occasions, you don't even have a
    high school understanding of logic, so this is far beyond your abilities.

    In the system everyone works in, Disjunction introduction is truth
    preserving and valid, and therefore so is the Principle of Explosion,
    as you have just admitted on the record above.




    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Mon Jun 29 08:55:48 2026
    From Newsgroup: comp.theory

    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition, >>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>> other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>> formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more earlier >>>>>>> statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is off-
    topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.


    POE is unprovable in both of these more sensible systems
    of logic. The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    Model theory was created only because keeping semantics
    directly within logic at the time was too complicated.
    It did make logic easier to work with and it also made
    logic diverge from correct reasoning.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    Relevance logic, also called relevant logic, is a
    kind of non-classical logic requiring the antecedent
    and consequent of implications to be relevantly related. https://en.wikipedia.org/wiki/Relevance_logic

    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is
    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Mon Jun 29 09:59:30 2026
    From Newsgroup: comp.theory

    On 6/29/2026 9:55 AM, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more
    earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.


    POE is unprovable in both of these more sensible systems
    of logic. The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    It does follow from the semantics, as you have admitted on the record
    (see below):

    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game. Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.


    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory on Mon Jun 29 09:00:12 2026
    From Newsgroup: comp.theory

    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many
    systems of analytic implication belonging >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability
    of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is
    famously featured in Lewis’ derivation of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula ψ from a contradiction of the form >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that >>>>>>>>>>>>>>>>>>>>>>>>>>>> when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is >>>>>>>>>>>>>>>>>>>>>>>>>> its problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make >>>>>>>>>>>>>>>>>>>>> it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>> statement can be proven as true.

    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use a >>>>>>>>>>>>>>>>>>>>> system that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law >>>>>>>>>>>>>>>>>>> of non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>>>>>>

    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists >>>>>>>>>>>>>>> a statement X such that the condition "At least one of >>>>>>>>>>>>>>> the following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>> exist a statement X such that the condition "At least one >>>>>>>>>>>>> of the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>>> can't be used in logic.  I didn't think I had to make that >>>>>>>>> explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>

    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the
    condition "At least one of the following statements is true" is >>>>>>>> false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a >>>>>> head game in your next reply or within one hour of you next post
    in this newsgroup will be taken as your official, on-the-record
    admission that Disjunction introduction is in fact truth
    preserving and valid, and therefore so is the Principle of Explosion. >>>>>>

    Let the record show that Peter Olcott made the following post in
    this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the
    above question or explain why it is a head game.  Therefore, as per >>>>> the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and
    valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting with
    the precondition that a contradiction has been proven, as you have
    admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory on Mon Jun 29 10:01:25 2026
    From Newsgroup: comp.theory

    On 6/29/2026 10:00 AM, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication belonging >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even know >>>>>>>>>>>>>>>>>>>>>>>>>>>>> that
    anyone else ever did this. I just knew that >>>>>>>>>>>>>>>>>>>>>>>>>>>>> when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is >>>>>>>>>>>>>>>>>>>>>>>>>>> its problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction enables >>>>>>>>>>>>>>>>>>>>>>> the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>>> statement can be proven as true.

    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use a >>>>>>>>>>>>>>>>>>>>>> system that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses its >>>>>>>>>>>>>>>>>>>> basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>> exists a statement X such that the condition "At least >>>>>>>>>>>>>>>> one of the following statements is true" is false. >>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>> exist a statement X such that the condition "At least one >>>>>>>>>>>>>> of the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>>>> can't be used in logic.  I didn't think I had to make that >>>>>>>>>> explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>

    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the
    condition "At least one of the following statements is true" is >>>>>>>>> false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is >>>>>>> a head game in your next reply or within one hour of you next
    post in this newsgroup will be taken as your official, on-the-
    record admission that Disjunction introduction is in fact truth >>>>>>> preserving and valid, and therefore so is the Principle of
    Explosion.


    Let the record show that Peter Olcott made the following post in
    this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the
    above question or explain why it is a head game.  Therefore, as
    per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and
    valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting with
    the precondition that a contradiction has been proven, as you have
    admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.


    And it seems you are one of those people, as you have admitted on the
    record above.


    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Tue Jun 30 10:55:17 2026
    From Newsgroup: comp.theory

    On 29/06/2026 16:23, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many
    systems of analytic implication belonging >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability
    of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is
    famously featured in Lewis’ derivation of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula ψ from a contradiction of the form >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that >>>>>>>>>>>>>>>>>>>>>>>>>>>> when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is >>>>>>>>>>>>>>>>>>>>>>>>>> its problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction enables the >>>>>>>>>>>>>>>>>>>>>> Principle of Explosion.


    Rejected, as you not liking the result doesn't make >>>>>>>>>>>>>>>>>>>>> it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>> statement can be proven as true.

    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use a >>>>>>>>>>>>>>>>>>>>> system that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the law >>>>>>>>>>>>>>>>>>> of non- contradiction goes away as it looses its basis. >>>>>>>>>>>>>>>>>>>

    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there exists >>>>>>>>>>>>>>> a statement X such that the condition "At least one of >>>>>>>>>>>>>>> the following statements is true" is false.

    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>> exist a statement X such that the condition "At least one >>>>>>>>>>>>> of the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>>> can't be used in logic.  I didn't think I had to make that >>>>>>>>> explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>

    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the
    condition "At least one of the following statements is true" is >>>>>>>> false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a >>>>>> head game in your next reply or within one hour of you next post
    in this newsgroup will be taken as your official, on-the-record
    admission that Disjunction introduction is in fact truth
    preserving and valid, and therefore so is the Principle of Explosion. >>>>>>

    Let the record show that Peter Olcott made the following post in
    this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the
    above question or explain why it is a head game.  Therefore, as per >>>>> the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and
    valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.

    One can construct a system where a truth-preserving operation is not
    valid, and must if one wants to construct a paraconsistent system,
    where some but not every sentence can be both PTS-true and PTS-false.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Tue Jun 30 11:10:22 2026
    From Newsgroup: comp.theory

    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who don't >>>>>>>>>> understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where
    eachstatement either is a premis or follows from one or more
    earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.

    Model theory was created only because keeping semantics
    directly within logic at the time was too complicated.
    It did make logic easier to work with and it also made
    logic diverge from correct reasoning.

    In a formal context the formal system specifies what reasoning is
    correct. In real world application the sules of ordinary logic are
    empirically correct, i.e., no situation is observed where the rules
    of logic are violated.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    A proof in a formal system is a finite string that satisfies certain
    syntactic rules specifiec for the system. There is no reference to
    any semantics.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory on Tue Jun 30 11:48:51 2026
    From Newsgroup: comp.theory

    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication belonging >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even know >>>>>>>>>>>>>>>>>>>>>>>>>>>>> that
    anyone else ever did this. I just knew that >>>>>>>>>>>>>>>>>>>>>>>>>>>>> when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is >>>>>>>>>>>>>>>>>>>>>>>>>>> its problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction enables >>>>>>>>>>>>>>>>>>>>>>> the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>>> statement can be proven as true.

    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use a >>>>>>>>>>>>>>>>>>>>>> system that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses its >>>>>>>>>>>>>>>>>>>> basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>> exists a statement X such that the condition "At least >>>>>>>>>>>>>>>> one of the following statements is true" is false. >>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>> exist a statement X such that the condition "At least one >>>>>>>>>>>>>> of the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>>>> can't be used in logic.  I didn't think I had to make that >>>>>>>>>> explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>

    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the
    condition "At least one of the following statements is true" is >>>>>>>>> false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is >>>>>>> a head game in your next reply or within one hour of you next
    post in this newsgroup will be taken as your official, on-the-
    record admission that Disjunction introduction is in fact truth >>>>>>> preserving and valid, and therefore so is the Principle of
    Explosion.


    Let the record show that Peter Olcott made the following post in
    this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the
    above question or explain why it is a head game.  Therefore, as
    per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and
    valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting with
    the precondition that a contradiction has been proven, as you have
    admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and
    the Moon is not made from green cheese and Donald Trump is not the one
    and only Lord and Savior Jesus Christ?
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Tue Jun 30 08:45:32 2026
    From Newsgroup: comp.theory

    On 6/30/2026 2:55 AM, Mikko wrote:
    On 29/06/2026 16:23, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote:
    On 6/27/2026 1:34 PM, dbush wrote:
    On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication belonging >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to its ilk) is
    the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> an arbitrary
    formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even know >>>>>>>>>>>>>>>>>>>>>>>>>>>>> that
    anyone else ever did this. I just knew that >>>>>>>>>>>>>>>>>>>>>>>>>>>>> when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that is >>>>>>>>>>>>>>>>>>>>>>>>>>> its problem.

    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>>>>>> language statement:


    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all.

    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction enables >>>>>>>>>>>>>>>>>>>>>>> the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>>> statement can be proven as true.

    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use a >>>>>>>>>>>>>>>>>>>>>> system that has a contradiction.


    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that prevents >>>>>>>>>>>>>>>>>>>>> infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses its >>>>>>>>>>>>>>>>>>>> basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/Principle_of_explosion#Proof >>>>>>>>>>>>>>>>>
    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>> exists a statement X such that the condition "At least >>>>>>>>>>>>>>>> one of the following statements is true" is false. >>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction.


    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>> exist a statement X such that the condition "At least one >>>>>>>>>>>>>> of the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>>
    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>>>> can't be used in logic.  I didn't think I had to make that >>>>>>>>>> explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>

    On second though, let's back up as that might confuse you.

    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the
    condition "At least one of the following statements is true" is >>>>>>>>> false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is >>>>>>> a head game in your next reply or within one hour of you next
    post in this newsgroup will be taken as your official, on-the-
    record admission that Disjunction introduction is in fact truth >>>>>>> preserving and valid, and therefore so is the Principle of
    Explosion.


    Let the record show that Peter Olcott made the following post in
    this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the
    above question or explain why it is a head game.  Therefore, as
    per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and
    valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different rules.
    That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.

    One can construct a system where a truth-preserving operation is not
    valid, and must if one wants to construct a paraconsistent system,
    where some but not every sentence can be both PTS-true and PTS-false.


    Current semantic entailment is the only inference step allowed.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Tue Jun 30 08:55:47 2026
    From Newsgroup: comp.theory

    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.


    Only because semantics is ignored.
    There is nothing semantically meaningful about a
    contradiction that derives anything at all besides FALSE.

    There is nothing semantically meaningful about FALSE
    that derives anything at all besides FALSE.

    Model theory was created only because keeping semantics
    directly within logic at the time was too complicated.
    It did make logic easier to work with and it also made
    logic diverge from correct reasoning.

    In a formal context the formal system specifies what reasoning is
    correct. In real world application the sules of ordinary logic are empirically correct, i.e., no situation is observed where the rules
    of logic are violated.


    The POE derives that Donald Trump is the one and only Lord
    and Savior Jesus Christ and Trump is not Christ therefore
    the POE is incorrect reasoning.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    A proof in a formal system is a finite string that satisfies certain syntactic rules specifiec for the system. There is no reference to
    any semantics.


    It makes the huge mistake of ignoring semantics.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Tue Jun 30 10:01:15 2026
    From Newsgroup: comp.theory

    On 6/30/2026 9:55 AM, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.


    Only because semantics is ignored.
    There is nothing semantically meaningful about a
    contradiction that derives anything at all besides FALSE.

    There is nothing semantically meaningful about FALSE
    that derives anything at all besides FALSE.

    False, as you have admitted otherwise on the record (see below):

    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game. Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Tue Jun 30 09:37:53 2026
    From Newsgroup: comp.theory

    On 6/30/2026 3:48 AM, Mikko wrote:
    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even know >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that >>>>>>>>>>>>>>>>>>>>>>>>>>>> is its problem.

    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>>>> statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use a >>>>>>>>>>>>>>>>>>>>>>> system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses >>>>>>>>>>>>>>>>>>>>> its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>> exists a statement X such that the condition "At least >>>>>>>>>>>>>>>>> one of the following statements is true" is false. >>>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>>> exist a statement X such that the condition "At least one >>>>>>>>>>>>>>> of the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>> true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>>>>> can't be used in logic.  I didn't think I had to make that >>>>>>>>>>> explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>>

    On second though, let's back up as that might confuse you. >>>>>>>>>>
    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the
    condition "At least one of the following statements is true" >>>>>>>>>> is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is >>>>>>>> a head game in your next reply or within one hour of you next >>>>>>>> post in this newsgroup will be taken as your official, on-the- >>>>>>>> record admission that Disjunction introduction is in fact truth >>>>>>>> preserving and valid, and therefore so is the Principle of
    Explosion.


    Let the record show that Peter Olcott made the following post in >>>>>>> this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the >>>>>>> above question or explain why it is a head game.  Therefore, as >>>>>>> per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and
    valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different
    rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting with
    the precondition that a contradiction has been proven, as you have
    admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and
    the Moon is not made from green cheese and Donald Trump is not the one
    and only Lord and Savior Jesus Christ?


    Counter-factual
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Wed Jul 1 09:46:49 2026
    From Newsgroup: comp.theory

    On 30/06/2026 17:37, olcott wrote:
    On 6/30/2026 3:48 AM, Mikko wrote:
    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of statement where eachstatement either is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that >>>>>>>>>>>>>>>>>>>>>>>>>>>>> is its problem.

    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>>>>> statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use >>>>>>>>>>>>>>>>>>>>>>>> a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses >>>>>>>>>>>>>>>>>>>>>> its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>> language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At least >>>>>>>>>>>>>>>>>> one of the following statements is true" is false. >>>>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is >>>>>>>>>>>>>>>> true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>>>> exist a statement X such that the condition "At least >>>>>>>>>>>>>>>> one of the following statements is true" is false? >>>>>>>>>>>>>>>>

    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>>> true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so >>>>>>>>>>>> it can't be used in logic.  I didn't think I had to make >>>>>>>>>>>> that explicit.

    However, let's go with it anyway because it still
    illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>>>

    On second though, let's back up as that might confuse you. >>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the >>>>>>>>>>> condition "At least one of the following statements is true" >>>>>>>>>>> is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it >>>>>>>>> is a head game in your next reply or within one hour of you >>>>>>>>> next post in this newsgroup will be taken as your official, on- >>>>>>>>> the- record admission that Disjunction introduction is in fact >>>>>>>>> truth preserving and valid, and therefore so is the Principle >>>>>>>>> of Explosion.


    Let the record show that Peter Olcott made the following post in >>>>>>>> this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the >>>>>>>> above question or explain why it is a head game.  Therefore, as >>>>>>>> per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and >>>>>>>> valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different
    rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting
    with the precondition that a contradiction has been proven, as you
    have admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and
    the Moon is not made from green cheese and Donald Trump is not the one
    and only Lord and Savior Jesus Christ?


    Counter-factual

    For logic the distinction between factual and counter-factual is not
    as imortant as the distinction between consistent and contradictory.
    As long as the premises are consistent they may be true about
    somesituation even if they are false in the intended interpretation. Contradictory premises cannot be all true in any interpretation.
    From contradictory or otherwise false premises it is possible to
    infer both true and false conclusions.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Wed Jul 1 09:50:02 2026
    From Newsgroup: comp.theory

    On 30/06/2026 16:45, olcott wrote:
    On 6/30/2026 2:55 AM, Mikko wrote:
    On 29/06/2026 16:23, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for
    Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even know >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence of >>>>>>>>>>>>>>>>>>>>>>>>>>>>> statement where eachstatement either is a >>>>>>>>>>>>>>>>>>>>>>>>>>>>> premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that >>>>>>>>>>>>>>>>>>>>>>>>>>>> is its problem.

    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>>>> statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use a >>>>>>>>>>>>>>>>>>>>>>> system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses >>>>>>>>>>>>>>>>>>>>> its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the
    propositional variables it is as obvious
    as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>>>>> statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>> exists a statement X such that the condition "At least >>>>>>>>>>>>>>>>> one of the following statements is true" is false. >>>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is true: >>>>>>>>>>>>>>>
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>>> exist a statement X such that the condition "At least one >>>>>>>>>>>>>>> of the following statements is true" is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>> true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so it >>>>>>>>>>> can't be used in logic.  I didn't think I had to make that >>>>>>>>>>> explicit.

    However, let's go with it anyway because it still illustrates >>>>>>>>>>> the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>>

    On second though, let's back up as that might confuse you. >>>>>>>>>>
    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the
    condition "At least one of the following statements is true" >>>>>>>>>> is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is >>>>>>>> a head game in your next reply or within one hour of you next >>>>>>>> post in this newsgroup will be taken as your official, on-the- >>>>>>>> record admission that Disjunction introduction is in fact truth >>>>>>>> preserving and valid, and therefore so is the Principle of
    Explosion.


    Let the record show that Peter Olcott made the following post in >>>>>>> this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the >>>>>>> above question or explain why it is a head game.  Therefore, as >>>>>>> per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and
    valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different
    rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.

    One can construct a system where a truth-preserving operation is not
    valid, and must if one wants to construct a paraconsistent system,
    where some but not every sentence can be both PTS-true and PTS-false.


    Current semantic entailment is the only inference step allowed.

    Every truth-prserving transformation is a correct semantic entailment.
    In particular, disjunction introduction is.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Wed Jul 1 09:53:39 2026
    From Newsgroup: comp.theory

    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.

    Only because semantics is ignored.

    A break from reality is a break from reality, no matter whether
    the semantics is ignored or considered. Though if there is no
    semantics, even any ignored one, there is no connection to
    reality to break.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Wed Jul 1 10:32:18 2026
    From Newsgroup: comp.theory

    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is
    off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Wed Jul 1 10:01:12 2026
    From Newsgroup: comp.theory

    On 7/1/2026 1:46 AM, Mikko wrote:
    On 30/06/2026 17:37, olcott wrote:
    On 6/30/2026 3:48 AM, Mikko wrote:
    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 5:52 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PAI (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> — given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of statement where eachstatement either >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is a premis or follows from one or more >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is its problem.

    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving >>>>>>>>>>>>>>>>>>>>>>>>> operations, when a contradiction is given as >>>>>>>>>>>>>>>>>>>>>>>>> true, any statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration >>>>>>>>>>>>>>>>>>>>>>>>> of *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid >>>>>>>>>>>>>>>>>>>>>>>>> of the principle of explosion is to be able to >>>>>>>>>>>>>>>>>>>>>>>>> use a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses >>>>>>>>>>>>>>>>>>>>>>> its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>> language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>> - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At >>>>>>>>>>>>>>>>>>> least one of the following statements is true" is false. >>>>>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is >>>>>>>>>>>>>>>>> true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement: >>>>>>>>>>>>>>>>>
    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>>>>> exist a statement X such that the condition "At least >>>>>>>>>>>>>>>>> one of the following statements is true" is false? >>>>>>>>>>>>>>>>>

    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>>>> true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so >>>>>>>>>>>>> it can't be used in logic.  I didn't think I had to make >>>>>>>>>>>>> that explicit.

    However, let's go with it anyway because it still
    illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>> true?


    On second though, let's back up as that might confuse you. >>>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language >>>>>>>>>>>> statement, does there exist a statement X such that the >>>>>>>>>>>> condition "At least one of the following statements is true" >>>>>>>>>>>> is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it >>>>>>>>>> is a head game in your next reply or within one hour of you >>>>>>>>>> next post in this newsgroup will be taken as your official, >>>>>>>>>> on- the- record admission that Disjunction introduction is in >>>>>>>>>> fact truth preserving and valid, and therefore so is the
    Principle of Explosion.


    Let the record show that Peter Olcott made the following post >>>>>>>>> in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the >>>>>>>>> above question or explain why it is a head game.  Therefore, as >>>>>>>>> per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and >>>>>>>>> valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different
    rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting
    with the precondition that a contradiction has been proven, as you
    have admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and
    the Moon is not made from green cheese and Donald Trump is not the one
    and only Lord and Savior Jesus Christ?


    Counter-factual

    For logic the distinction between factual and counter-factual is not
    as imortant as the distinction between consistent and contradictory.

    Counter-factual may indicate a psychotic break from reality.

    As long as the premises are consistent they may be true about
    some situation even if they are false in the intended interpretation. Contradictory premises cannot be all true in any interpretation.
    From contradictory or otherwise false premises it is possible to
    infer both true and false conclusions.

    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Wed Jul 1 10:04:37 2026
    From Newsgroup: comp.theory

    On 7/1/2026 1:50 AM, Mikko wrote:
    On 30/06/2026 16:45, olcott wrote:
    On 6/30/2026 2:55 AM, Mikko wrote:
    On 29/06/2026 16:23, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote:
    On 6/27/2026 5:52 PM, dbush wrote:
    On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of PAI >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication— >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of statement where eachstatement either is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a premis or follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, that >>>>>>>>>>>>>>>>>>>>>>>>>>>>> is its problem.

    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving operations, >>>>>>>>>>>>>>>>>>>>>>>> when a contradiction is given as true, any >>>>>>>>>>>>>>>>>>>>>>>> statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration of >>>>>>>>>>>>>>>>>>>>>>>> *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid of >>>>>>>>>>>>>>>>>>>>>>>> the principle of explosion is to be able to use >>>>>>>>>>>>>>>>>>>>>>>> a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses >>>>>>>>>>>>>>>>>>>>>> its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>> language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At least >>>>>>>>>>>>>>>>>> one of the following statements is true" is false. >>>>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is >>>>>>>>>>>>>>>> true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>>>> exist a statement X such that the condition "At least >>>>>>>>>>>>>>>> one of the following statements is true" is false? >>>>>>>>>>>>>>>>

    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>>> true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so >>>>>>>>>>>> it can't be used in logic.  I didn't think I had to make >>>>>>>>>>>> that explicit.

    However, let's go with it anyway because it still
    illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" true? >>>>>>>>>>>>

    On second though, let's back up as that might confuse you. >>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language
    statement, does there exist a statement X such that the >>>>>>>>>>> condition "At least one of the following statements is true" >>>>>>>>>>> is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it >>>>>>>>> is a head game in your next reply or within one hour of you >>>>>>>>> next post in this newsgroup will be taken as your official, on- >>>>>>>>> the- record admission that Disjunction introduction is in fact >>>>>>>>> truth preserving and valid, and therefore so is the Principle >>>>>>>>> of Explosion.


    Let the record show that Peter Olcott made the following post in >>>>>>>> this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the >>>>>>>> above question or explain why it is a head game.  Therefore, as >>>>>>>> per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and >>>>>>>> valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different
    rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.

    One can construct a system where a truth-preserving operation is not
    valid, and must if one wants to construct a paraconsistent system,
    where some but not every sentence can be both PTS-true and PTS-false.


    Current semantic entailment is the only inference step allowed.

    Every truth-prserving transformation is a correct semantic entailment.
    In particular, disjunction introduction is.


    That is counter-factual. POE is misconstrued as truth preserving.
    Every element of logic is utterly discarded and only the underlying
    semantics is preserved.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Wed Jul 1 10:06:02 2026
    From Newsgroup: comp.theory

    On 7/1/2026 1:53 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.

    Only because semantics is ignored.

    A break from reality is a break from reality, no matter whether
    the semantics is ignored or considered. Though if there is no
    semantics, even any ignored one, there is no connection to
    reality to break.


    Ignoring semantics is always a break from reality.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Wed Jul 1 10:25:09 2026
    From Newsgroup: comp.theory

    On 7/1/2026 2:32 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>> the rejection of the classically valid principle of Addition, >>>>>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people who >>>>>>>>>>>>> don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem.

    So you're saying that in the following natural language statement: >>>>>>>>>

    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.


    Parry’s logic of Analytic Implication
    and Relevance logic are two sensible systems
    that get rid of the Principle of Explosion.

    It was dead-obviously correct to anyone paying
    any attention at all that every contradiction
    only semantically entails FALSE.

    The only reason that it took more than five minutes
    for everyone to agree to this is that logicians are
    a herd of sheep and mindlessly obey what they have
    been taught even if this means that they must jump
    off a cliff.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Wed Jul 1 13:34:58 2026
    From Newsgroup: comp.theory

    On 7/1/2026 11:04 AM, olcott wrote:
    On 7/1/2026 1:50 AM, Mikko wrote:
    On 30/06/2026 16:45, olcott wrote:
    On 6/30/2026 2:55 AM, Mikko wrote:
    On 29/06/2026 16:23, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 5:52 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PAI (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> — given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of statement where eachstatement either >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is a premis or follows from one or more >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is its problem.

    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving >>>>>>>>>>>>>>>>>>>>>>>>> operations, when a contradiction is given as >>>>>>>>>>>>>>>>>>>>>>>>> true, any statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration >>>>>>>>>>>>>>>>>>>>>>>>> of *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid >>>>>>>>>>>>>>>>>>>>>>>>> of the principle of explosion is to be able to >>>>>>>>>>>>>>>>>>>>>>>>> use a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses >>>>>>>>>>>>>>>>>>>>>>> its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>> language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>> - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At >>>>>>>>>>>>>>>>>>> least one of the following statements is true" is false. >>>>>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is >>>>>>>>>>>>>>>>> true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement: >>>>>>>>>>>>>>>>>
    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>>>>> exist a statement X such that the condition "At least >>>>>>>>>>>>>>>>> one of the following statements is true" is false? >>>>>>>>>>>>>>>>>

    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>>>> true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so >>>>>>>>>>>>> it can't be used in logic.  I didn't think I had to make >>>>>>>>>>>>> that explicit.

    However, let's go with it anyway because it still
    illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>> true?


    On second though, let's back up as that might confuse you. >>>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language >>>>>>>>>>>> statement, does there exist a statement X such that the >>>>>>>>>>>> condition "At least one of the following statements is true" >>>>>>>>>>>> is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it >>>>>>>>>> is a head game in your next reply or within one hour of you >>>>>>>>>> next post in this newsgroup will be taken as your official, >>>>>>>>>> on- the- record admission that Disjunction introduction is in >>>>>>>>>> fact truth preserving and valid, and therefore so is the
    Principle of Explosion.


    Let the record show that Peter Olcott made the following post >>>>>>>>> in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the >>>>>>>>> above question or explain why it is a head game.  Therefore, as >>>>>>>>> per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and >>>>>>>>> valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different
    rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.

    One can construct a system where a truth-preserving operation is not
    valid, and must if one wants to construct a paraconsistent system,
    where some but not every sentence can be both PTS-true and PTS-false.


    Current semantic entailment is the only inference step allowed.

    Every truth-prserving transformation is a correct semantic entailment.
    In particular, disjunction introduction is.


    That is counter-factual. POE is misconstrued as truth preserving.

    False, as you have admitted on the record (see below):

    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game. Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Wed Jul 1 13:37:13 2026
    From Newsgroup: comp.theory

    On 7/1/2026 11:25 AM, olcott wrote:
    On 7/1/2026 2:32 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>
    So you're saying that in the following natural language
    statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.


    Parry’s logic of Analytic Implication
    and Relevance logic are two sensible systems
    that get rid of the Principle of Explosion.

    It was dead-obviously correct to anyone paying
    any attention at all that every contradiction
    only semantically entails FALSE.

    False, as you have admitted on the record:

    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game. Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Wed Jul 1 13:02:21 2026
    From Newsgroup: comp.theory

    On 7/1/2026 12:37 PM, dbush wrote:
    On 7/1/2026 11:25 AM, olcott wrote:
    On 7/1/2026 2:32 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere >>>>>>>>>>>>>> (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>>> eachstatement either is a premis or follows from one or >>>>>>>>>>>>> more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.


    Parry’s logic of Analytic Implication
    and Relevance logic are two sensible systems
    that get rid of the Principle of Explosion.

    It was dead-obviously correct to anyone paying
    any attention at all that every contradiction
    only semantically entails FALSE.

    False, as you have admitted on the record:


    Liar

    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
      > Q also can't bake a birthday cake, this does not make
      > Q in any way "incomplete" relative to what it was
      > defined to do.
      > ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game.  Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.

    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Wed Jul 1 14:17:01 2026
    From Newsgroup: comp.theory

    On 7/1/2026 2:02 PM, olcott wrote:
    On 7/1/2026 12:37 PM, dbush wrote:
    On 7/1/2026 11:25 AM, olcott wrote:
    On 7/1/2026 2:32 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when >>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>> where eachstatement either is a premis or follows from one >>>>>>>>>>>>>> or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable. >>>>>>>> Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.


    Parry’s logic of Analytic Implication
    and Relevance logic are two sensible systems
    that get rid of the Principle of Explosion.

    It was dead-obviously correct to anyone paying
    any attention at all that every contradiction
    only semantically entails FALSE.

    False, as you have admitted on the record:


    Liar

    And now you lie about making such an admission when the evidence is
    right there below in black and white for all to see.

    Your dishonestly knows no bounds.


    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:
    ;
    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------
    ;
    In the following natural language statement:
    ;
    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------
    ;
    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least
    one
    of the following statements is true" is false?
    ;
    ;
    Head games will be ignored.
    ;
    ;
    Explain in detail how this is a head game.
    ;
    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record
    admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.
    ;
    ;
    Let the record show that Peter Olcott made the following post in this
    newsgroup:
    ;
    On 6/28/2026 10:52 PM, olcott wrote:
    ;  > Q also can't bake a birthday cake, this does not make
    ;  > Q in any way "incomplete" relative to what it was
    ;  > defined to do.
    ;  > ...
    ;
    And more that one hour has passed with no attempt to answer the above
    question or explain why it is a head game.  Therefore, as per the
    above
    criteria:
    ;
    Let The Record Show
    ;
    That Peter Olcott
    ;
    Has *Officially* Admitted:
    ;
    That Disjunction introduction is in fact truth preserving and
    valid, and
    therefore so is the Principle of Explosion.




    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Thu Jul 2 09:21:35 2026
    From Newsgroup: comp.theory

    On 01/07/2026 18:01, olcott wrote:
    On 7/1/2026 1:46 AM, Mikko wrote:
    On 30/06/2026 17:37, olcott wrote:
    On 6/30/2026 3:48 AM, Mikko wrote:
    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 5:52 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PAI (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> valid principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ψ is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> implication — given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derivation of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of statement where eachstatement either >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is a premis or follows from one or more >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that is its problem. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving >>>>>>>>>>>>>>>>>>>>>>>>>> operations, when a contradiction is given as >>>>>>>>>>>>>>>>>>>>>>>>>> true, any statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration >>>>>>>>>>>>>>>>>>>>>>>>>> of *why* a formal system whose axioms lead to >>>>>>>>>>>>>>>>>>>>>>>>>> a contradiction is useless. >>>>>>>>>>>>>>>>>>>>>>>>>>
    The only reason someone would want to get rid >>>>>>>>>>>>>>>>>>>>>>>>>> of the principle of explosion is to be able to >>>>>>>>>>>>>>>>>>>>>>>>>> use a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning. >>>>>>>>>>>>>>>>>>>>>>>>>

    If you get rid of the principle of explosion, >>>>>>>>>>>>>>>>>>>>>>>> the law of non- contradiction goes away as it >>>>>>>>>>>>>>>>>>>>>>>> looses its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>> language statement:

    -------------------------------------- >>>>>>>>>>>>>>>>>>>> At least one of the following statements is true: >>>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>> - <X>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>>
    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At >>>>>>>>>>>>>>>>>>>> least one of the following statements is true" is >>>>>>>>>>>>>>>>>>>> false.

    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is >>>>>>>>>>>>>>>>>> true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement: >>>>>>>>>>>>>>>>>>
    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does >>>>>>>>>>>>>>>>>> there exist a statement X such that the condition "At >>>>>>>>>>>>>>>>>> least one of the following statements is true" is false? >>>>>>>>>>>>>>>>>>

    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the >>>>>>>>>>>>>>>> sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so >>>>>>>>>>>>>> it can't be used in logic.  I didn't think I had to make >>>>>>>>>>>>>> that explicit.

    However, let's go with it anyway because it still >>>>>>>>>>>>>> illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>>> true?


    On second though, let's back up as that might confuse you. >>>>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language >>>>>>>>>>>>> statement, does there exist a statement X such that the >>>>>>>>>>>>> condition "At least one of the following statements is >>>>>>>>>>>>> true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it >>>>>>>>>>> is a head game in your next reply or within one hour of you >>>>>>>>>>> next post in this newsgroup will be taken as your official, >>>>>>>>>>> on- the- record admission that Disjunction introduction is in >>>>>>>>>>> fact truth preserving and valid, and therefore so is the >>>>>>>>>>> Principle of Explosion.


    Let the record show that Peter Olcott made the following post >>>>>>>>>> in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer >>>>>>>>>> the above question or explain why it is a head game.
    Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and >>>>>>>>>> valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition, >>>>>>>>> sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different >>>>>>>> rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting
    with the precondition that a contradiction has been proven, as you >>>>>> have admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and
    the Moon is not made from green cheese and Donald Trump is not the one >>>> and only Lord and Savior Jesus Christ?


    Counter-factual

    For logic the distinction between factual and counter-factual is not
    as imortant as the distinction between consistent and contradictory.

    Counter-factual may indicate a psychotic break from reality.

    No, it does not. It is much more common than anything psychotic.
    Besudes, any mention of anything psychotic is off-topic in these
    groups.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Thu Jul 2 09:27:07 2026
    From Newsgroup: comp.theory

    On 01/07/2026 18:04, olcott wrote:
    On 7/1/2026 1:50 AM, Mikko wrote:
    On 30/06/2026 16:45, olcott wrote:
    On 6/30/2026 2:55 AM, Mikko wrote:
    On 29/06/2026 16:23, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote:
    On 6/27/2026 6:30 PM, dbush wrote:
    On 6/27/2026 7:22 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 5:52 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PAI (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically valid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> — given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way to >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. I >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> figured
    all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> a set of
    premises that you cannot pop in another >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sentence
    from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion.

    By popping in another sentence from out >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of nowhere
    (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is
    derived.

    The usual meaning of proof is a sequence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of statement where eachstatement either >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is a premis or follows from one or more >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> is its problem.

    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion.


    Rejected, as you not liking the result doesn't >>>>>>>>>>>>>>>>>>>>>>>>> make it invalid.

    Through a series of truth preserving >>>>>>>>>>>>>>>>>>>>>>>>> operations, when a contradiction is given as >>>>>>>>>>>>>>>>>>>>>>>>> true, any statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration >>>>>>>>>>>>>>>>>>>>>>>>> of *why* a formal system whose axioms lead to a >>>>>>>>>>>>>>>>>>>>>>>>> contradiction is useless.

    The only reason someone would want to get rid >>>>>>>>>>>>>>>>>>>>>>>>> of the principle of explosion is to be able to >>>>>>>>>>>>>>>>>>>>>>>>> use a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>> it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning.


    If you get rid of the principle of explosion, the >>>>>>>>>>>>>>>>>>>>>>> law of non- contradiction goes away as it looses >>>>>>>>>>>>>>>>>>>>>>> its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth-preserving >>>>>>>>>>>>>>>>>>>>> operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>> language statement:

    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>> - <X>
    --------------------------------------

    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At >>>>>>>>>>>>>>>>>>> least one of the following statements is true" is false. >>>>>>>>>>>>>>>>>>>
    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then.

    Given that the following natural language statement is >>>>>>>>>>>>>>>>> true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement: >>>>>>>>>>>>>>>>>
    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>> - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Where <X> is any natural language statement, does there >>>>>>>>>>>>>>>>> exist a statement X such that the condition "At least >>>>>>>>>>>>>>>>> one of the following statements is true" is false? >>>>>>>>>>>>>>>>>

    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>>>> true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, so >>>>>>>>>>>>> it can't be used in logic.  I didn't think I had to make >>>>>>>>>>>>> that explicit.

    However, let's go with it anyway because it still
    illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>> true?


    On second though, let's back up as that might confuse you. >>>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language >>>>>>>>>>>> statement, does there exist a statement X such that the >>>>>>>>>>>> condition "At least one of the following statements is true" >>>>>>>>>>>> is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it >>>>>>>>>> is a head game in your next reply or within one hour of you >>>>>>>>>> next post in this newsgroup will be taken as your official, >>>>>>>>>> on- the- record admission that Disjunction introduction is in >>>>>>>>>> fact truth preserving and valid, and therefore so is the
    Principle of Explosion.


    Let the record show that Peter Olcott made the following post >>>>>>>>> in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the >>>>>>>>> above question or explain why it is a head game.  Therefore, as >>>>>>>>> per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and >>>>>>>>> valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition,
    sometimes also referred to as Disjunction Introduction. In

    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary
    formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different
    rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.

    One can construct a system where a truth-preserving operation is not
    valid, and must if one wants to construct a paraconsistent system,
    where some but not every sentence can be both PTS-true and PTS-false.


    Current semantic entailment is the only inference step allowed.

    Every truth-prserving transformation is a correct semantic entailment.
    In particular, disjunction introduction is.

    That is counter-factual. POE is misconstrued as truth preserving.

    No, it is not. Nobody has claimed that POE preserves anythjing. The
    iimportance of POE is in what it reveals.

    POE is the equivalnet of the common understanding that a liar cannot
    be trusted even though a good liar tells the truth more often than a
    lie.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Thu Jul 2 09:29:11 2026
    From Newsgroup: comp.theory

    On 01/07/2026 18:06, olcott wrote:
    On 7/1/2026 1:53 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>
    So you're saying that in the following natural language
    statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.

    Only because semantics is ignored.

    A break from reality is a break from reality, no matter whether
    the semantics is ignored or considered. Though if there is no
    semantics, even any ignored one, there is no connection to
    reality to break.


    Ignoring semantics is always a break from reality.

    So is any semantics other than real world semantics.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Thu Jul 2 09:31:33 2026
    From Newsgroup: comp.theory

    On 01/07/2026 18:25, olcott wrote:
    On 7/1/2026 2:32 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere
    (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>> eachstatement either is a premis or follows from one or more >>>>>>>>>>>> earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>
    So you're saying that in the following natural language
    statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed is >>>>>>>> off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.

    Parry’s logic of Analytic Implication
    and Relevance logic are two sensible systems
    that get rid of the Principle of Explosion.

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Thu Jul 2 09:37:54 2026
    From Newsgroup: comp.theory

    On 7/2/2026 1:21 AM, Mikko wrote:
    On 01/07/2026 18:01, olcott wrote:
    On 7/1/2026 1:46 AM, Mikko wrote:
    On 30/06/2026 17:37, olcott wrote:
    On 6/30/2026 3:48 AM, Mikko wrote:
    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:30 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 7:22 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 5:52 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PAI (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> valid principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ψ is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> implication — given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derivation of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> I figured
    all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that
    anyone else ever did this. I just knew >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that when
    trying to find out what is deduced >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a set of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> another sentence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> out of nowhere >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sequence of statement where >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> eachstatement either is a premis or >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> statements

    Except with Disjunction introduction, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that is its problem. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion. >>>>>>>>>>>>>>>>>>>>>>>>>>>>

    Rejected, as you not liking the result >>>>>>>>>>>>>>>>>>>>>>>>>>> doesn't make it invalid. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    Through a series of truth preserving >>>>>>>>>>>>>>>>>>>>>>>>>>> operations, when a contradiction is given as >>>>>>>>>>>>>>>>>>>>>>>>>>> true, any statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a demonstration >>>>>>>>>>>>>>>>>>>>>>>>>>> of *why* a formal system whose axioms lead to >>>>>>>>>>>>>>>>>>>>>>>>>>> a contradiction is useless. >>>>>>>>>>>>>>>>>>>>>>>>>>>
    The only reason someone would want to get rid >>>>>>>>>>>>>>>>>>>>>>>>>>> of the principle of explosion is to be able >>>>>>>>>>>>>>>>>>>>>>>>>>> to use a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of >>>>>>>>>>>>>>>>>>>>>>>>>> explosion
    it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning. >>>>>>>>>>>>>>>>>>>>>>>>>>

    If you get rid of the principle of explosion, >>>>>>>>>>>>>>>>>>>>>>>>> the law of non- contradiction goes away as it >>>>>>>>>>>>>>>>>>>>>>>>> looses its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth- >>>>>>>>>>>>>>>>>>>>>>> preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>> language statement:

    -------------------------------------- >>>>>>>>>>>>>>>>>>>>> At least one of the following statements is true: >>>>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>>> - <X>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>>>
    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At >>>>>>>>>>>>>>>>>>>>> least one of the following statements is true" is >>>>>>>>>>>>>>>>>>>>> false.

    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then. >>>>>>>>>>>>>>>>>>>
    Given that the following natural language statement >>>>>>>>>>>>>>>>>>> is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement: >>>>>>>>>>>>>>>>>>>
    --------------------------------------
    At least one of the following statements is true: >>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>> - <X>
    --------------------------------------

    Where <X> is any natural language statement, does >>>>>>>>>>>>>>>>>>> there exist a statement X such that the condition "At >>>>>>>>>>>>>>>>>>> least one of the following statements is true" is false? >>>>>>>>>>>>>>>>>>>

    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the >>>>>>>>>>>>>>>>> sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, >>>>>>>>>>>>>>> so it can't be used in logic.  I didn't think I had to >>>>>>>>>>>>>>> make that explicit.

    However, let's go with it anyway because it still >>>>>>>>>>>>>>> illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the sun" >>>>>>>>>>>>>>> true?


    On second though, let's back up as that might confuse you. >>>>>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language >>>>>>>>>>>>>> statement, does there exist a statement X such that the >>>>>>>>>>>>>> condition "At least one of the following statements is >>>>>>>>>>>>>> true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how >>>>>>>>>>>> it is a head game in your next reply or within one hour of >>>>>>>>>>>> you next post in this newsgroup will be taken as your >>>>>>>>>>>> official, on- the- record admission that Disjunction
    introduction is in fact truth preserving and valid, and >>>>>>>>>>>> therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post >>>>>>>>>>> in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make >>>>>>>>>>>  > Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer >>>>>>>>>>> the above question or explain why it is a head game.
    Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and >>>>>>>>>>> valid, and therefore so is the Principle of Explosion.



    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many
    systems of analytic implication belonging to its ilk) is

    the rejection of the classically valid principle of Addition, >>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>
    other words, the principle leading from a formula ϕ to a
    disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>> formula. Parry blamed on this principle the derivability
    of the paradoxes of strict implication—given that it is
    famously featured in Lewis’ derivation of an arbitrary
    formula ψ from a contradiction of the form ϕ ∧ ¬ϕ.

    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different >>>>>>>>> rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting >>>>>>> with the precondition that a contradiction has been proven, as
    you have admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and >>>>> the Moon is not made from green cheese and Donald Trump is not the one >>>>> and only Lord and Savior Jesus Christ?


    Counter-factual

    For logic the distinction between factual and counter-factual is not
    as imortant as the distinction between consistent and contradictory.

    Counter-factual may indicate a psychotic break from reality.

    No, it does not. It is much more common than anything psychotic.
    Besudes, any mention of anything psychotic is off-topic in these
    groups.


    x = "The Moon is made from green cheese"
    y = "Donald Trump is the one and only Lord and Savior Jesus Christ:
    POE concludes (x ∧ ¬x) ⊢ y

    "the principle of explosion is the theorem according to
    which any statement can be proven from a contradiction" https://en.wikipedia.org/wiki/Principle_of_explosion

    When you pay attention to the meaning of the words
    and correctly apply correct semantic entailment on
    the basis of the meaning of those words then the
    principle of explosion is a PSYCHOTIC BREAK FROM REALITY.
    Relevance logic solved this by requiring relevance. https://plato.stanford.edu/entries/logic-relevance/

    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    https://philarchive.org/archive/SZMASL
    So that a new premise cannot be inserted in
    a chain-of-reasoning from out of nowhere

    The terrible mistake that logic made was to remove
    semantics from logical inference. This does result in
    a PSYCHOTIC BREAK FROM REALITY, making it relevant to
    these groups.

    Also the computation groups are relevant to sci.logic
    and sci.math because computation exposes gaps in the
    reasoning that logic and math assumes away.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Thu Jul 2 09:40:00 2026
    From Newsgroup: comp.theory

    On 7/2/2026 1:29 AM, Mikko wrote:
    On 01/07/2026 18:06, olcott wrote:
    On 7/1/2026 1:53 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere >>>>>>>>>>>>>> (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>>> eachstatement either is a premis or follows from one or >>>>>>>>>>>>> more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.

    Only because semantics is ignored.

    A break from reality is a break from reality, no matter whether
    the semantics is ignored or considered. Though if there is no
    semantics, even any ignored one, there is no connection to
    reality to break.


    Ignoring semantics is always a break from reality.

    So is any semantics other than real world semantics.


    Hypotheticals are useful for making decisions.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Thu Jul 2 09:40:57 2026
    From Newsgroup: comp.theory

    On 7/2/2026 1:31 AM, Mikko wrote:
    On 01/07/2026 18:25, olcott wrote:
    On 7/1/2026 2:32 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when
    trying to find out what is deduced from a set of
    premises that you cannot pop in another sentence
    from out of nowhere and get a correct conclusion.

    By popping in another sentence from out of nowhere >>>>>>>>>>>>>> (as it shows above) the principle of explosion is
    derived.

    The usual meaning of proof is a sequence of statement where >>>>>>>>>>>>> eachstatement either is a premis or follows from one or >>>>>>>>>>>>> more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable.
    Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.

    Parry’s logic of Analytic Implication
    and Relevance logic are two sensible systems
    that get rid of the Principle of Explosion.

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.


    Then you are irrational
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Thu Jul 2 10:42:10 2026
    From Newsgroup: comp.theory

    On 7/2/2026 10:37 AM, olcott wrote:
    On 7/2/2026 1:21 AM, Mikko wrote:
    On 01/07/2026 18:01, olcott wrote:
    On 7/1/2026 1:46 AM, Mikko wrote:
    On 30/06/2026 17:37, olcott wrote:
    On 6/30/2026 3:48 AM, Mikko wrote:
    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:30 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 7:22 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 5:52 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PAI (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> valid principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> where ψ is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> implication — given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derivation of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> I figured >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> knew that when >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a set of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> another sentence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> out of nowhere >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sequence of statement where >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> eachstatement either is a premis or >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> statements >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Except with Disjunction introduction, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that is its problem. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    Rejected, as you not liking the result >>>>>>>>>>>>>>>>>>>>>>>>>>>> doesn't make it invalid. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Through a series of truth preserving >>>>>>>>>>>>>>>>>>>>>>>>>>>> operations, when a contradiction is given as >>>>>>>>>>>>>>>>>>>>>>>>>>>> true, any statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a >>>>>>>>>>>>>>>>>>>>>>>>>>>> demonstration of *why* a formal system whose >>>>>>>>>>>>>>>>>>>>>>>>>>>> axioms lead to a contradiction is useless. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The only reason someone would want to get >>>>>>>>>>>>>>>>>>>>>>>>>>>> rid of the principle of explosion is to be >>>>>>>>>>>>>>>>>>>>>>>>>>>> able to use a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>> explosion
    it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning. >>>>>>>>>>>>>>>>>>>>>>>>>>>

    If you get rid of the principle of explosion, >>>>>>>>>>>>>>>>>>>>>>>>>> the law of non- contradiction goes away as it >>>>>>>>>>>>>>>>>>>>>>>>>> looses its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth- >>>>>>>>>>>>>>>>>>>>>>>> preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>> language statement:

    -------------------------------------- >>>>>>>>>>>>>>>>>>>>>> At least one of the following statements is true: >>>>>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>>>> - <X>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>>>>
    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At >>>>>>>>>>>>>>>>>>>>>> least one of the following statements is true" is >>>>>>>>>>>>>>>>>>>>>> false.

    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then. >>>>>>>>>>>>>>>>>>>>
    Given that the following natural language statement >>>>>>>>>>>>>>>>>>>> is true:

    -------------------------------------- >>>>>>>>>>>>>>>>>>>> Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>> -------------------------------------- >>>>>>>>>>>>>>>>>>>>
    In the following natural language statement: >>>>>>>>>>>>>>>>>>>>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>> At least one of the following statements is true: >>>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>> - <X>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>>
    Where <X> is any natural language statement, does >>>>>>>>>>>>>>>>>>>> there exist a statement X such that the condition >>>>>>>>>>>>>>>>>>>> "At least one of the following statements is true" >>>>>>>>>>>>>>>>>>>> is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the >>>>>>>>>>>>>>>>>> sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, >>>>>>>>>>>>>>>> so it can't be used in logic.  I didn't think I had to >>>>>>>>>>>>>>>> make that explicit.

    However, let's go with it anyway because it still >>>>>>>>>>>>>>>> illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the >>>>>>>>>>>>>>>> sun" true?


    On second though, let's back up as that might confuse you. >>>>>>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language >>>>>>>>>>>>>>> statement, does there exist a statement X such that the >>>>>>>>>>>>>>> condition "At least one of the following statements is >>>>>>>>>>>>>>> true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how >>>>>>>>>>>>> it is a head game in your next reply or within one hour of >>>>>>>>>>>>> you next post in this newsgroup will be taken as your >>>>>>>>>>>>> official, on- the- record admission that Disjunction >>>>>>>>>>>>> introduction is in fact truth preserving and valid, and >>>>>>>>>>>>> therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following >>>>>>>>>>>> post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make >>>>>>>>>>>>  > Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer >>>>>>>>>>>> the above question or explain why it is a head game.
    Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving >>>>>>>>>>>> and valid, and therefore so is the Principle of Explosion. >>>>>>>>>>>>


    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>
    the rejection of the classically valid principle of Addition, >>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>
    other words, the principle leading from a formula ϕ to a >>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>
    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different >>>>>>>>>> rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting >>>>>>>> with the precondition that a contradiction has been proven, as >>>>>>>> you have admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and >>>>>> the Moon is not made from green cheese and Donald Trump is not the >>>>>> one
    and only Lord and Savior Jesus Christ?


    Counter-factual

    For logic the distinction between factual and counter-factual is not
    as imortant as the distinction between consistent and contradictory.

    Counter-factual may indicate a psychotic break from reality.

    No, it does not. It is much more common than anything psychotic.
    Besudes, any mention of anything psychotic is off-topic in these
    groups.


    x = "The Moon is made from green cheese"
    y = "Donald Trump is the one and only Lord and Savior Jesus Christ:
    POE concludes (x ∧ ¬x) ⊢ y

    "the principle of explosion is the theorem according to
     which any statement can be proven from a contradiction" https://en.wikipedia.org/wiki/Principle_of_explosion

    Which you agreed on the record is a vaild truth preserving line of
    reasoning (see below):

    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game. Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.


    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Fri Jul 3 11:17:10 2026
    From Newsgroup: comp.theory

    On 02/07/2026 17:37, olcott wrote:
    On 7/2/2026 1:21 AM, Mikko wrote:
    On 01/07/2026 18:01, olcott wrote:
    On 7/1/2026 1:46 AM, Mikko wrote:
    On 30/06/2026 17:37, olcott wrote:
    On 6/30/2026 3:48 AM, Mikko wrote:
    On 29/06/2026 17:00, olcott wrote:
    On 6/29/2026 8:23 AM, dbush wrote:
    On 6/29/2026 9:17 AM, polcott wrote:
    On 6/29/2026 7:08 AM, dbush wrote:
    On 6/29/2026 12:13 AM, olcott wrote:
    On 6/28/2026 10:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    On 6/27/2026 9:24 PM, olcott wrote:
    On 6/27/2026 8:08 PM, dbush wrote:
    On 6/27/2026 7:56 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:30 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 7:22 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 5:52 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 6:40 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:34 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:29 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 1:24 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:03 PM, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 12:54 PM, dbush wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 11:11 AM, polcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/27/2026 2:08 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 15:49, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 6/26/2026 1:49 AM, Mikko wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> On 26/06/2026 04:32, olcott wrote: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> William T. Parry, Entailment Logics >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> gets rid of Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to prevent the principle of explosion >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    A simple logical matrix and sequent >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> calculus for >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The main and distinctive feature of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PAI (and of the many >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> systems of analytic implication >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> belonging to its ilk) is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the rejection of the classically >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> valid principle of Addition, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sometimes also referred to as >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Disjunction Introduction. In >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> other words, the principle leading >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a formula ϕ to a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> where ψ is an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula. Parry blamed on this >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> principle the derivability >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> of the paradoxes of strict >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> implication — given that it is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> famously featured in Lewis’ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derivation of an arbitrary >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    He also gets rid of an efficient way >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> to convince people who don't >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> understand much of logic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    As I recently showed in another post. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> I figured >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> all this out on my own. I didn't even >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> know that >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> anyone else ever did this. I just >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> knew that when >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> trying to find out what is deduced >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from a set of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> premises that you cannot pop in >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> another sentence >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> from out of nowhere and get a correct >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> conclusion. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    By popping in another sentence from >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> out of nowhere >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> (as it shows above) the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> explosion is >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> sequence of statement where >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> eachstatement either is a premis or >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> follows from one or more earlier >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> statements >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Except with Disjunction introduction, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> that is its problem. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> natural language statement: >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    It is a key issue in that it creates the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> psychotic break from reality known as the >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Principle of Explosion, otherwise it may >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> make no difference at all. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Stay on topic or I will block you. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Explain in detail how the below which you >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> dishonestly trimmed is off- topic. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    The topic is how Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>>>>>>>> enables the
    Principle of Explosion. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>

    Rejected, as you not liking the result >>>>>>>>>>>>>>>>>>>>>>>>>>>> doesn't make it invalid. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Through a series of truth preserving >>>>>>>>>>>>>>>>>>>>>>>>>>>> operations, when a contradiction is given as >>>>>>>>>>>>>>>>>>>>>>>>>>>> true, any statement can be proven as true. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The principle of explosion is a >>>>>>>>>>>>>>>>>>>>>>>>>>>> demonstration of *why* a formal system whose >>>>>>>>>>>>>>>>>>>>>>>>>>>> axioms lead to a contradiction is useless. >>>>>>>>>>>>>>>>>>>>>>>>>>>>
    The only reason someone would want to get >>>>>>>>>>>>>>>>>>>>>>>>>>>> rid of the principle of explosion is to be >>>>>>>>>>>>>>>>>>>>>>>>>>>> able to use a system that has a contradiction. >>>>>>>>>>>>>>>>>>>>>>>>>>>>

    My reason to get rid of the principle of >>>>>>>>>>>>>>>>>>>>>>>>>>> explosion
    it to get rid of anything and everything that >>>>>>>>>>>>>>>>>>>>>>>>>>> prevents
    infallibly correct reasoning. >>>>>>>>>>>>>>>>>>>>>>>>>>>

    If you get rid of the principle of explosion, >>>>>>>>>>>>>>>>>>>>>>>>>> the law of non- contradiction goes away as it >>>>>>>>>>>>>>>>>>>>>>>>>> looses its basis.


    You keep failing to pay close enough attention. >>>>>>>>>>>>>>>>>>>>>>>>> I only get rid of the POE by getting rid of >>>>>>>>>>>>>>>>>>>>>>>>> Disjunction introduction.

    Which you can't do because it's a truth- >>>>>>>>>>>>>>>>>>>>>>>> preserving operation.

    1) P ∧ ¬P    // Premise
    2) P          // Conjunction elimination >>>>>>>>>>>>>>>>>>>>>>> 3) ¬P        // Conjunction elimination >>>>>>>>>>>>>>>>>>>>>>> 4) P ∨ Q      // Disjunction introduction >>>>>>>>>>>>>>>>>>>>>>> 5) Q          // Disjunctive syllogism >>>>>>>>>>>>>>>>>>>>>>> https://en.wikipedia.org/wiki/
    Principle_of_explosion#Proof

    When you insert English meanings into the >>>>>>>>>>>>>>>>>>>>>>> propositional variables it is as obvious >>>>>>>>>>>>>>>>>>>>>>> as a pie in the fact the DI IS NOT TRUTH PRESERVING. >>>>>>>>>>>>>>>>>>>>>>
    So you're saying that in the following natural >>>>>>>>>>>>>>>>>>>>>> language statement:

    -------------------------------------- >>>>>>>>>>>>>>>>>>>>>> At least one of the following statements is true: >>>>>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>>>> - <X>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>>>>
    Where <X> is any natural language statement, there >>>>>>>>>>>>>>>>>>>>>> exists a statement X such that the condition "At >>>>>>>>>>>>>>>>>>>>>> least one of the following statements is true" is >>>>>>>>>>>>>>>>>>>>>> false.

    Name it.


    That is not Disjunction introduction combined with >>>>>>>>>>>>>>>>>>>>> Disjunctive syllogism, it is bare Disjunction. >>>>>>>>>>>>>>>>>>>>>

    Let me spell it out more explicitly then. >>>>>>>>>>>>>>>>>>>>
    Given that the following natural language statement >>>>>>>>>>>>>>>>>>>> is true:

    -------------------------------------- >>>>>>>>>>>>>>>>>>>> Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>> -------------------------------------- >>>>>>>>>>>>>>>>>>>>
    In the following natural language statement: >>>>>>>>>>>>>>>>>>>>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>> At least one of the following statements is true: >>>>>>>>>>>>>>>>>>>> - Earth is the third planet from the sun. >>>>>>>>>>>>>>>>>>>> - <X>
    -------------------------------------- >>>>>>>>>>>>>>>>>>>>
    Where <X> is any natural language statement, does >>>>>>>>>>>>>>>>>>>> there exist a statement X such that the condition >>>>>>>>>>>>>>>>>>>> "At least one of the following statements is true" >>>>>>>>>>>>>>>>>>>> is false?


    Where X is "What time is it?"



    Is the statement "Earth is the third planet from the >>>>>>>>>>>>>>>>>> sun" true?

    We have a type mismatch error.



    The statement you gave isn't a truth-bearing statement, >>>>>>>>>>>>>>>> so it can't be used in logic.  I didn't think I had to >>>>>>>>>>>>>>>> make that explicit.

    However, let's go with it anyway because it still >>>>>>>>>>>>>>>> illustrates the point.

    So I'll ask again:

    Is the statement "Earth is the third planet from the >>>>>>>>>>>>>>>> sun" true?


    On second though, let's back up as that might confuse you. >>>>>>>>>>>>>>>
    Given that <X> is any *truth bearing* natural language >>>>>>>>>>>>>>> statement, does there exist a statement X such that the >>>>>>>>>>>>>>> condition "At least one of the following statements is >>>>>>>>>>>>>>> true" is false?


    Head games will be ignored.
    That you did so well on the other things
    so I will not block you.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how >>>>>>>>>>>>> it is a head game in your next reply or within one hour of >>>>>>>>>>>>> you next post in this newsgroup will be taken as your >>>>>>>>>>>>> official, on- the- record admission that Disjunction >>>>>>>>>>>>> introduction is in fact truth preserving and valid, and >>>>>>>>>>>>> therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following >>>>>>>>>>>> post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make >>>>>>>>>>>>  > Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer >>>>>>>>>>>> the above question or explain why it is a head game.
    Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving >>>>>>>>>>>> and valid, and therefore so is the Principle of Explosion. >>>>>>>>>>>>


    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for
    Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>
    the rejection of the classically valid principle of Addition, >>>>>>>>>>> sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>
    other words, the principle leading from a formula ϕ to a >>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>
    https://philarchive.org/archive/SZMASL


    So someone came up with a different system that has different >>>>>>>>>> rules. That has no bearing on existing systems.


    The bearing that it has on existing systems is

    None, as you can't remove a truth-preserving operation.



    that
    it corrects their psychotic break from reality that
    allows one to prove that Donald Trump is the one and
    only Lord and Savior on the basis of a totally irrelevant
    contradiction.

    It follows from a series of truth-preserving operations starting >>>>>>>> with the precondition that a contradiction has been proven, as >>>>>>>> you have admitted above on the record.

    Only people having actual psychosis would conclude
    that "The Moon is made from green cheese" AND
    "The Moon is NOT made from green cheese" SEMANTICALLY
    PROVES that Donald Trump is the one and only Lord
    and Savior Jesus Christ.

    How do you know that somewhere the Moon is made from green cheese and >>>>>> the Moon is not made from green cheese and Donald Trump is not the >>>>>> one
    and only Lord and Savior Jesus Christ?


    Counter-factual

    For logic the distinction between factual and counter-factual is not
    as imortant as the distinction between consistent and contradictory.

    Counter-factual may indicate a psychotic break from reality.

    No, it does not. It is much more common than anything psychotic.
    Besudes, any mention of anything psychotic is off-topic in these
    groups.

    x = "The Moon is made from green cheese"
    y = "Donald Trump is the one and only Lord and Savior Jesus Christ:
    POE concludes (x ∧ ¬x) ⊢ y

    "the principle of explosion is the theorem according to
     which any statement can be proven from a contradiction" https://en.wikipedia.org/wiki/Principle_of_explosion

    When you pay attention to the meaning of the words
    and correctly apply correct semantic entailment on
    the basis of the meaning of those words then the
    principle of explosion is a PSYCHOTIC BREAK FROM REALITY.

    No, it is not. The premise x above is a break from reality. But that
    is not in logic, it was introduced by you. Even without the principle
    of explosion it is possible to infer a false conclusion from a false
    premise. The principle of explosion merely facilitates tinding a
    conclusion that is so obviously false that it convincingly proves
    that the remise is false. But false is false even if the proof is
    something less obvious.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Fri Jul 3 11:22:14 2026
    From Newsgroup: comp.theory

    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:29 AM, Mikko wrote:
    On 01/07/2026 18:06, olcott wrote:
    On 7/1/2026 1:53 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when >>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>> where eachstatement either is a premis or follows from one >>>>>>>>>>>>>> or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable. >>>>>>>> Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies
    of a false premise, which already is a break from reality even
    when no consequence is inferred.

    Only because semantics is ignored.

    A break from reality is a break from reality, no matter whether
    the semantics is ignored or considered. Though if there is no
    semantics, even any ignored one, there is no connection to
    reality to break.


    Ignoring semantics is always a break from reality.

    So is any semantics other than real world semantics.

    Hypotheticals are useful for making decisions.

    Which is an example of the usefulness of a break from reality. It
    als shows that calling a break from reality "psychotic" without
    further consideration.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,sci.math,comp.theory,comp.ai.philosophy on Fri Jul 3 11:24:20 2026
    From Newsgroup: comp.theory

    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:31 AM, Mikko wrote:
    On 01/07/2026 18:25, olcott wrote:
    On 7/1/2026 2:32 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction Introduction. In >>>>>>>>>>>>>>>>> other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured
    all this out on my own. I didn't even know that
    anyone else ever did this. I just knew that when >>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>> where eachstatement either is a premis or follows from one >>>>>>>>>>>>>> or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable. >>>>>>>> Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.

    Parry’s logic of Analytic Implication

    If the intent was to include that in the denotation you failed
    to say something important.

    Parry’s logic of Analytic Implication
    and Relevance logic are two sensible systems
    that get rid of the Principle of Explosion.

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.

    Then you are irrational

    Matter of opinion, but I think that most of people would consder
    getting rid of fires is more rational that getting rid of fire
    alarms.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Fri Jul 3 09:46:43 2026
    From Newsgroup: comp.theory

    On 7/3/2026 3:17 AM, Mikko wrote:
    On 02/07/2026 17:37, olcott wrote:

    x = "The Moon is made from green cheese"
    y = "Donald Trump is the one and only Lord and Savior Jesus Christ:
    POE concludes (x ∧ ¬x) ⊢ y

    "the principle of explosion is the theorem according to
      which any statement can be proven from a contradiction"
    https://en.wikipedia.org/wiki/Principle_of_explosion

    When you pay attention to the meaning of the words
    and correctly apply correct semantic entailment on
    the basis of the meaning of those words then the
    principle of explosion is a PSYCHOTIC BREAK FROM REALITY.

    No, it is not. The premise x above is a break from reality. But that
    is not in logic, it was introduced by you. Even without the principle
    of explosion it is possible to infer a false conclusion from a false
    premise.

    Yes. From "I am 35 feet tall" ⊢ "I am 35 feet tall"
    and as you said my premise is literally FALSE
    (P ∧ ~P) ⊢ FALSE

    The principle of explosion merely facilitates tinding a
    conclusion that is so obviously false that it convincingly proves
    that the remise is false.

    There is nothing semantically relevant that can be
    proven from a contradiction besides bare FALSE and
    bare FALSE only entails bare FALSE.

    But false is false even if the proof is
    something less obvious.

    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.logic,comp.ai.philosophy on Fri Jul 3 09:50:26 2026
    From Newsgroup: comp.theory

    On 7/3/2026 3:22 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:29 AM, Mikko wrote:
    On 01/07/2026 18:06, olcott wrote:
    On 7/1/2026 1:53 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince people >>>>>>>>>>>>>>>>> who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>> where eachstatement either is a premis or follows from >>>>>>>>>>>>>>> one or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly trimmed >>>>>>>>>>> is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable. >>>>>>>>> Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies >>>>>>> of a false premise, which already is a break from reality even
    when no consequence is inferred.

    Only because semantics is ignored.

    A break from reality is a break from reality, no matter whether
    the semantics is ignored or considered. Though if there is no
    semantics, even any ignored one, there is no connection to
    reality to break.


    Ignoring semantics is always a break from reality.

    So is any semantics other than real world semantics.

    Hypotheticals are useful for making decisions.

    Which is an example of the usefulness of a break from reality. It
    als shows that calling a break from reality "psychotic" without
    further consideration.


    That Donald Trump might start WW III is a hypothetical
    that can possibly be is useful. That Donald Trump is
    the one and only Lord and Savior Jesus Christ is a
    hypothetical that cannot possible be making it useless.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Fri Jul 3 10:04:51 2026
    From Newsgroup: comp.theory

    On 7/3/2026 3:24 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:31 AM, Mikko wrote:

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.

    Then you are irrational

    Matter of opinion,

    Matter of correctly and coherently computing the notion
    of truth. My correction to the Principle of Explosion:
    (P ∧ ~P) ⊢ FALSE
    FALSE ⊢ FALSE

    but I think that most of people would consder
    getting rid of fires is more rational that getting rid of fire
    alarms.


    It is not a fire alarm it is getting rid of semantics
    within inference. My correct reasoning correction to
    logic gets rid of every type of inference besides
    semantic entailment.

    Validity and Soundness
    A deductive argument is said to be valid if
    and only if it takes a form that makes it
    impossible for the premises to be true and
    the conclusion nevertheless to be false.
    Otherwise, a deductive argument is said to
    be invalid. https://iep.utm.edu/val-snd/

    *That big mistake is corrected thusly*
    A deductive argument is said to be valid if
    and only if its conclusion is a necessary
    consequence of all of its premises Otherwise,
    a deductive argument is said to be invalid.

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 09:37:45 2026
    From Newsgroup: comp.theory

    On 03/07/2026 17:46, olcott wrote:
    On 7/3/2026 3:17 AM, Mikko wrote:
    On 02/07/2026 17:37, olcott wrote:

    x = "The Moon is made from green cheese"
    y = "Donald Trump is the one and only Lord and Savior Jesus Christ:
    POE concludes (x ∧ ¬x) ⊢ y

    "the principle of explosion is the theorem according to
      which any statement can be proven from a contradiction"
    https://en.wikipedia.org/wiki/Principle_of_explosion

    When you pay attention to the meaning of the words
    and correctly apply correct semantic entailment on
    the basis of the meaning of those words then the
    principle of explosion is a PSYCHOTIC BREAK FROM REALITY.

    No, it is not. The premise x above is a break from reality. But that
    is not in logic, it was introduced by you. Even without the principle
    of explosion it is possible to infer a false conclusion from a false
    premise.

    Yes. From "I am 35 feet tall" ⊢ "I am 35 feet tall"
    and as you said my premise is literally FALSE
    (P ∧ ~P) ⊢ FALSE

    The principle of explosion merely facilitates tinding a
    conclusion that is so obviously false that it convincingly proves
    that the remise is false.

    There is nothing semantically relevant that can be
    proven from a contradiction besides bare FALSE and
    bare FALSE only entails bare FALSE.

    Yes, there is. From the contradiction "I have blue eyes and
    I don't have blue eyes" one can prove "I have blue eyes" and
    "I don't have blue eyes", both of which are semantically
    relevant, and one of which in addition is false.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 09:47:28 2026
    From Newsgroup: comp.theory

    On 03/07/2026 18:04, olcott wrote:
    On 7/3/2026 3:24 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:31 AM, Mikko wrote:

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.

    Then you are irrational

    Matter of opinion,

    Matter of correctly and coherently computing the notion
    of truth. My correction to the Principle of Explosion:
    (P ∧ ~P) ⊢ FALSE
    FALSE ⊢ FALSE

    but I think that most of people would consder
    getting rid of fires is more rational that getting rid of fire
    alarms.

    It is not a fire alarm it is getting rid of semantics
    within inference. My correct reasoning correction to
    logic gets rid of every type of inference besides
    semantic entailment.

    Getting rid of any type of inference does not make much difference
    as long as you get the same conclusions through other inferences.
    Only getting rid of some conscusions it makes a significant
    difference. But you have never shown an example of getting rid of
    a conclusion without losing a semantic entailment.

    Validity and Soundness
    A deductive argument is said to be valid if
    and only if it takes a form that makes it
    impossible for the premises to be true and
    the conclusion nevertheless to be false.
    Otherwise, a deductive argument is said to
    be invalid. https://iep.utm.edu/val-snd/

    *That big mistake is corrected thusly*
    A deductive argument is said to be valid if
    and only if its conclusion is a necessary
    consequence of all of its premises Otherwise,
    a deductive argument is said to be invalid.

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    You don't need any of above if you have ¬, ∨, and ∧.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.logic,comp.ai.philosophy on Sat Jul 4 11:15:00 2026
    From Newsgroup: comp.theory

    On 03/07/2026 17:50, olcott wrote:
    On 7/3/2026 3:22 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:29 AM, Mikko wrote:
    On 01/07/2026 18:06, olcott wrote:
    On 7/1/2026 1:53 AM, Mikko wrote:
    On 30/06/2026 16:55, olcott wrote:
    On 6/30/2026 3:10 AM, Mikko wrote:
    On 29/06/2026 16:55, olcott wrote:
    On 6/28/2026 4:32 AM, Mikko wrote:
    On 27/06/2026 21:29, olcott wrote:
    On 6/27/2026 1:24 PM, dbush wrote:
    On 6/27/2026 2:03 PM, olcott wrote:
    On 6/27/2026 12:54 PM, dbush wrote:
    On 6/27/2026 11:11 AM, polcott wrote:
    On 6/27/2026 2:08 AM, Mikko wrote:
    On 26/06/2026 15:49, olcott wrote:
    On 6/26/2026 1:49 AM, Mikko wrote:
    On 26/06/2026 04:32, olcott wrote:
    William T. Parry, Entailment Logics
    gets rid of Disjunction introduction
    to prevent the principle of explosion

    A simple logical matrix and sequent calculus for >>>>>>>>>>>>>>>>>>> Parry’s logic of Analytic Implication

    The main and distinctive feature of PAI (and of the many >>>>>>>>>>>>>>>>>>> systems of analytic implication belonging to its ilk) is >>>>>>>>>>>>>>>>>>> the rejection of the classically valid principle of >>>>>>>>>>>>>>>>>>> Addition,
    sometimes also referred to as Disjunction >>>>>>>>>>>>>>>>>>> Introduction. In
    other words, the principle leading from a formula ϕ to a >>>>>>>>>>>>>>>>>>> disjunction of the form ϕ ∨ ψ, where ψ is an arbitrary >>>>>>>>>>>>>>>>>>> formula. Parry blamed on this principle the derivability >>>>>>>>>>>>>>>>>>> of the paradoxes of strict implication—given that it is >>>>>>>>>>>>>>>>>>> famously featured in Lewis’ derivation of an arbitrary >>>>>>>>>>>>>>>>>>> formula ψ from a contradiction of the form ϕ ∧ ¬ϕ. >>>>>>>>>>>>>>>>>>>
    https://philarchive.org/archive/SZMASL

    He also gets rid of an efficient way to convince >>>>>>>>>>>>>>>>>> people who don't
    understand much of logic.

    As I recently showed in another post. I figured >>>>>>>>>>>>>>>>> all this out on my own. I didn't even know that >>>>>>>>>>>>>>>>> anyone else ever did this. I just knew that when >>>>>>>>>>>>>>>>> trying to find out what is deduced from a set of >>>>>>>>>>>>>>>>> premises that you cannot pop in another sentence >>>>>>>>>>>>>>>>> from out of nowhere and get a correct conclusion. >>>>>>>>>>>>>>>>>
    By popping in another sentence from out of nowhere >>>>>>>>>>>>>>>>> (as it shows above) the principle of explosion is >>>>>>>>>>>>>>>>> derived.

    The usual meaning of proof is a sequence of statement >>>>>>>>>>>>>>>> where eachstatement either is a premis or follows from >>>>>>>>>>>>>>>> one or more earlier
    statements

    Except with Disjunction introduction, that is its problem. >>>>>>>>>>>>>>
    So you're saying that in the following natural language >>>>>>>>>>>>>> statement:


    It is a key issue in that it creates the
    psychotic break from reality known as the
    Principle of Explosion, otherwise it may
    make no difference at all.

    Stay on topic or I will block you.

    Explain in detail how the below which you dishonestly >>>>>>>>>>>> trimmed is off- topic.


    The topic is how Disjunction introduction enables the
    Principle of Explosion.

    It does not. In any sensible logic every tautology is provable. >>>>>>>>>> Then the principle of explosion follows.

    POE is unprovable in both of these more sensible systems
    of logic.

    THe expression "these system" above does not denote.


    Parry’s logic of Analytic Implication

    Relevance Logic
    https://plato.stanford.edu/entries/logic-relevance/

    The POE is an actual psychotic break from
    reality when one pays full and complete attention to
    the underlying semantics and does not stupidly take
    semantics out of logic and put it in a separate model.

    No, it is not. The principle of explosion is about consequencies >>>>>>>> of a false premise, which already is a break from reality even >>>>>>>> when no consequence is inferred.

    Only because semantics is ignored.

    A break from reality is a break from reality, no matter whether
    the semantics is ignored or considered. Though if there is no
    semantics, even any ignored one, there is no connection to
    reality to break.


    Ignoring semantics is always a break from reality.

    So is any semantics other than real world semantics.

    Hypotheticals are useful for making decisions.

    Which is an example of the usefulness of a break from reality. It
    als shows that calling a break from reality "psychotic" without
    further consideration.

    That Donald Trump might start WW III is a hypothetical
    that can possibly be is useful.

    Whether Donald Trump will start WW III is not yet known, so that
    cannot be called an example of counter-factual.

    That Donald Trump is the one and only Lord and Savior Jesus Christ
    is a hypothetical that cannot possible be making it useless.

    Maybe, but irrelevent as you did not claim it be useful when you
    presented it.
    --
    Mikko

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From Mikko@mikko.levanto@iki.fi to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 11:16:55 2026
    From Newsgroup: comp.theory

    On 03/07/2026 18:04, olcott wrote:
    On 7/3/2026 3:24 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:31 AM, Mikko wrote:

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.

    Then you are irrational

    Matter of opinion,

    Matter of correctly and coherently computing the notion
    of truth.

    You did not compute correctely, let aloone coherently, whether
    I an irrational. You onlu presented your opinion about it.
    --
    Mikko
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 08:15:52 2026
    From Newsgroup: comp.theory

    On 7/4/2026 1:37 AM, Mikko wrote:
    On 03/07/2026 17:46, olcott wrote:
    On 7/3/2026 3:17 AM, Mikko wrote:
    On 02/07/2026 17:37, olcott wrote:

    x = "The Moon is made from green cheese"
    y = "Donald Trump is the one and only Lord and Savior Jesus Christ:
    POE concludes (x ∧ ¬x) ⊢ y

    "the principle of explosion is the theorem according to
      which any statement can be proven from a contradiction"
    https://en.wikipedia.org/wiki/Principle_of_explosion

    When you pay attention to the meaning of the words
    and correctly apply correct semantic entailment on
    the basis of the meaning of those words then the
    principle of explosion is a PSYCHOTIC BREAK FROM REALITY.

    No, it is not. The premise x above is a break from reality. But that
    is not in logic, it was introduced by you. Even without the principle
    of explosion it is possible to infer a false conclusion from a false
    premise.

    Yes. From "I am 35 feet tall" ⊢ "I am 35 feet tall"
    and as you said my premise is literally FALSE
    (P ∧ ~P) ⊢ FALSE

    The principle of explosion merely facilitates tinding a
    conclusion that is so obviously false that it convincingly proves
    that the remise is false.

    There is nothing semantically relevant that can be
    proven from a contradiction besides bare FALSE and
    bare FALSE only entails bare FALSE.

    Yes, there is. From the contradiction "I have blue eyes and
    I don't have blue eyes" one can prove "I have blue eyes" and
    "I don't have blue eyes", both of which are semantically
    relevant, and one of which in addition is false.


    That is greatly restricted from the POE.
    (P ∧ ~P) ⊢ FALSE // is what can really be proved semantically
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From dbush@dbush.mobile@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 09:19:29 2026
    From Newsgroup: comp.theory

    On 7/4/2026 9:15 AM, olcott wrote:
    On 7/4/2026 1:37 AM, Mikko wrote:
    On 03/07/2026 17:46, olcott wrote:
    On 7/3/2026 3:17 AM, Mikko wrote:
    On 02/07/2026 17:37, olcott wrote:

    x = "The Moon is made from green cheese"
    y = "Donald Trump is the one and only Lord and Savior Jesus Christ:
    POE concludes (x ∧ ¬x) ⊢ y

    "the principle of explosion is the theorem according to
      which any statement can be proven from a contradiction"
    https://en.wikipedia.org/wiki/Principle_of_explosion

    When you pay attention to the meaning of the words
    and correctly apply correct semantic entailment on
    the basis of the meaning of those words then the
    principle of explosion is a PSYCHOTIC BREAK FROM REALITY.

    No, it is not. The premise x above is a break from reality. But that
    is not in logic, it was introduced by you. Even without the principle
    of explosion it is possible to infer a false conclusion from a false
    premise.

    Yes. From "I am 35 feet tall" ⊢ "I am 35 feet tall"
    and as you said my premise is literally FALSE
    (P ∧ ~P) ⊢ FALSE

    The principle of explosion merely facilitates tinding a
    conclusion that is so obviously false that it convincingly proves
    that the remise is false.

    There is nothing semantically relevant that can be
    proven from a contradiction besides bare FALSE and
    bare FALSE only entails bare FALSE.

    Yes, there is. From the contradiction "I have blue eyes and
    I don't have blue eyes" one can prove "I have blue eyes" and
    "I don't have blue eyes", both of which are semantically
    relevant, and one of which in addition is false.


    That is greatly restricted from the POE.
     (P ∧ ~P) ⊢ FALSE // is what can really be proved semantically


    Nope, as you have admitted otherwise on the record (see below):

    On 6/28/2026 11:56 PM, dbush wrote:
    On 6/27/2026 11:34 PM, dbush wrote:
    On 6/27/2026 11:23 PM, olcott wrote:
    On 6/27/2026 9:02 PM, dbush wrote:
    On 6/27/2026 9:53 PM, dbush wrote:
    On 6/27/2026 9:49 PM, olcott wrote:
    On 6/27/2026 8:42 PM, dbush wrote:
    On 6/27/2026 9:40 PM, olcott wrote:
    On 6/27/2026 8:29 PM, dbush wrote:
    Given that the following natural language statement is true:

    --------------------------------------
    Earth is the third planet from the sun.
    --------------------------------------

    In the following natural language statement:

    --------------------------------------
    At least one of the following statements is true:
    - Earth is the third planet from the sun.
    - <X>
    --------------------------------------

    Given that <X> is any *truth bearing* natural language statement,
    does there exist a statement X such that the condition "At least one
    of the following statements is true" is false?


    Head games will be ignored.


    Explain in detail how this is a head game.

    Failure to either answer the above question or explain how it is a
    head game in your next reply or within one hour of you next post in
    this newsgroup will be taken as your official, on-the-record admission
    that Disjunction introduction is in fact truth preserving and valid,
    and therefore so is the Principle of Explosion.


    Let the record show that Peter Olcott made the following post in this newsgroup:

    On 6/28/2026 10:52 PM, olcott wrote:
    Q also can't bake a birthday cake, this does not make
    Q in any way "incomplete" relative to what it was
    defined to do.
    ...

    And more that one hour has passed with no attempt to answer the above question or explain why it is a head game. Therefore, as per the above criteria:

    Let The Record Show

    That Peter Olcott

    Has *Officially* Admitted:

    That Disjunction introduction is in fact truth preserving and valid, and therefore so is the Principle of Explosion.
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 08:21:08 2026
    From Newsgroup: comp.theory

    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:
    On 7/3/2026 3:24 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:31 AM, Mikko wrote:

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.

    Then you are irrational

    Matter of opinion,

    Matter of correctly and coherently computing the notion
    of truth. My correction to the Principle of Explosion:
    (P ∧ ~P) ⊢ FALSE
    FALSE ⊢ FALSE

    but I think that most of people would consder
    getting rid of fires is more rational that getting rid of fire
    alarms.

    It is not a fire alarm it is getting rid of semantics
    within inference. My correct reasoning correction to
    logic gets rid of every type of inference besides
    semantic entailment.

    Getting rid of any type of inference does not make much difference
    as long as you get the same conclusions through other inferences.
    Only getting rid of some conscusions it makes a significant
    difference. But you have never shown an example of getting rid of
    a conclusion without losing a semantic entailment.


    POE always breaks semantic entailment

    Validity and Soundness
    A deductive argument is said to be valid if
    and only if it takes a form that makes it
    impossible for the premises to be true and
    the conclusion nevertheless to be false.
    Otherwise, a deductive argument is said to
    be invalid. https://iep.utm.edu/val-snd/

    *That big mistake is corrected thusly*
    A deductive argument is said to be valid if
    and only if its conclusion is a necessary
    consequence of all of its premises Otherwise,
    a deductive argument is said to be invalid.

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    You don't need any of above if you have ¬, ∨, and ∧.


    The notion of valid inference that I just established
    is the foundation of all semantic entailment.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 09:08:03 2026
    From Newsgroup: comp.theory

    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity. □ is a unary operator and
    an expression like P □ Q makes absolutely no sense.

    If you want to use this as a binary operator you'd actually need to
    *define* it. You don't seem to grasp this. You can't just introduce a
    new operator and expect people to know what it means.

    Also, moving into the domain of modal logic would be an incredibly
    strange thing for you to do given that in previous posts you claimed to
    reject the idea of models. But modal logic is *replete* with models.
    Modal logic operates over a set of many models. □P means that P is true
    in all accessible models of the system.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 11:44:06 2026
    From Newsgroup: comp.theory

    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    □ is a unary operator and
    an expression like P □ Q makes absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    If you want to use this as a binary operator you'd actually need to
    *define* it. You don't seem to grasp this. You can't just introduce a
    new operator and expect people to know what it means.


    □ Already means necessity, it is not that hard unless
    one makes great effort to pretend to not understand
    what is already unequivocally clear.

    Also, moving into the domain of modal logic would be an incredibly
    strange thing for you to do given that in previous posts you claimed to

    The only thing that I am using is logical necessity.

    reject the idea of models. But modal logic is *replete* with models.
    Modal logic operates over a set of many models. □P means that P is true
    in all accessible models of the system.

    André

    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy on Sat Jul 4 10:59:06 2026
    From Newsgroup: comp.theory

    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes absolutely no >> sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q), not as the nonsensical P □ Q. But you claim to have gotten rid of →, so how this is to be
    interpreted remains a mystery (and getting rid of → makes no sense since
    → represents a specific truth table which still exists regardless of
    whether you've assigned a symbol to it or not)

    If you want to use this as a binary operator you'd actually need to
    *define* it. You don't seem to grasp this. You can't just introduce a
    new operator and expect people to know what it means.


    □ Already means necessity, it is not that hard unless
    one makes great effort to pretend to not understand
    what is already unequivocally clear. >
    Also, moving into the domain of modal logic would be an incredibly
    strange thing for you to do given that in previous posts you claimed to

    The only thing that I am using is logical necessity.

    So how would you interpret 'necessity' without models?

    André

    reject the idea of models. But modal logic is *replete* with models.
    Modal logic operates over a set of many models. □P means that P is
    true in all accessible models of the system.

    André



    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,comp.ai.philosophy,sci.math,alt.philosophy on Sat Jul 4 12:09:40 2026
    From Newsgroup: comp.theory

    On 7/4/2026 3:15 AM, Mikko wrote:
    On 03/07/2026 17:50, olcott wrote:
    On 7/3/2026 3:22 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:

    Hypotheticals are useful for making decisions.

    Which is an example of the usefulness of a break from reality. It
    als shows that calling a break from reality "psychotic" without
    further consideration.

    That Donald Trump might start WW III is a hypothetical
    that can possibly be is useful.

    Whether Donald Trump will start WW III is not yet known, so that
    cannot be called an example of counter-factual.


    It is an example of hypothetical. You did not pay attention.

    That Donald Trump is the one and only Lord and Savior Jesus Christ
    is a hypothetical that cannot possible be making it useless.

    Maybe, but irrelevent as you did not claim it be useful when you
    presented it.

    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 12:11:13 2026
    From Newsgroup: comp.theory

    On 7/4/2026 3:16 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:
    On 7/3/2026 3:24 AM, Mikko wrote:
    On 02/07/2026 17:40, olcott wrote:
    On 7/2/2026 1:31 AM, Mikko wrote:

    Getting rid of the principle of explosion makes as much sense as
    getting rid of fire alarms. It makes much more sense to get rid
    of fires and false premises.

    Then you are irrational

    Matter of opinion,

    Matter of correctly and coherently computing the notion
    of truth.

    You did not compute correctely, let aloone coherently, whether
    I an irrational. You onlu presented your opinion about it.


    Merely rhetoric entirely bereft of a supporting basis.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 15:58:13 2026
    From Newsgroup: comp.theory

    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes absolutely >>> no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    P □ Q P → Q
    0 ? 0 0 1 0
    0 ? 1 0 1 1
    1 0 0 1 0 0
    1 1 1 1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true when P is true and Q is true
    (c) otherwise does not have a truth value.

    not as the nonsensical P □
    Q. But you claim to have gotten rid of →, so how this is to be
    interpreted remains a mystery (and getting rid of → makes no sense since → represents a specific truth table which still exists regardless of whether you've assigned a symbol to it or not)

    If you want to use this as a binary operator you'd actually need to
    *define* it. You don't seem to grasp this. You can't just introduce a
    new operator and expect people to know what it means.


    □ Already means necessity, it is not that hard unless
    one makes great effort to pretend to not understand
    what is already unequivocally clear. >
    Also, moving into the domain of modal logic would be an incredibly
    strange thing for you to do given that in previous posts you claimed to

    The only thing that I am using is logical necessity.

    So how would you interpret 'necessity' without models?


    To make it easy to understand we have the above
    propositional logic truth tables. They provide
    the framework.

    André

    reject the idea of models. But modal logic is *replete* with models.
    Modal logic operates over a set of many models. □P means that P is
    true in all accessible models of the system.

    André




    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 15:29:31 2026
    From Newsgroup: comp.theory

    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes absolutely >>>> no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity between
    P and Q". Necessity applies to propositions. It doesn't hold *between*
    things.

    □(P → Q) means that Q is necessarily implied by P. If you mean something other than that you're really going to have to clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. If a
    truth table contains any symbol other than T or F, you're dealing with a
    three or more valued logic which means you have to completely redefine
    every single logical operator before you can proceed.

    And there's nothing about the above table which in any way captures the meaning of 'necessity' so it's entirely unclear why you want to use the
    □ symbol here. Your '□' doesn't have any relation to necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing as
    operator overloading, so you can't take a unary operator and use it for
    some ill-defined binary operation as well. You need a new symbol since □
    is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal logic is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use of models?

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 16:36:14 2026
    From Newsgroup: comp.theory

    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes absolutely >>>>> no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity between
    P and Q". Necessity applies to propositions. It doesn't hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean something other than that you're really going to have to clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. If a
    truth table contains any symbol other than T or F, you're dealing with a three or more valued logic which means you have to completely redefine
    every single logical operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)

    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    And there's nothing about the above table which in any way captures the meaning of 'necessity' so it's entirely unclear why you want to use the
    □ symbol here. Your '□' doesn't have any relation to necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing as
    operator overloading, so you can't take a unary operator and use it for
    some ill-defined binary operation as well. You need a new symbol since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal logic is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use of
    models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 16:11:52 2026
    From Newsgroup: comp.theory

    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes
    absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity
    between P and Q". Necessity applies to propositions. It doesn't hold
    *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean
    something other than that you're really going to have to clarify what
    you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. If a
    truth table contains any symbol other than T or F, you're dealing with
    a three or more valued logic which means you have to completely
    redefine every single logical operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any attempt to
    explain what is meant by this (by you).

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you can't do
    that, then your use of 'necessary' is completely meaningless verbiage.

    And there's nothing about the above table which in any way captures
    the meaning of 'necessity' so it's entirely unclear why you want to
    use the □ symbol here. Your '□' doesn't have any relation to necessity >> any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing as
    operator overloading, so you can't take a unary operator and use it
    for some ill-defined binary operation as well. You need a new symbol
    since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal logic
    is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use of
    models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.

    Propositional calculus uses models. It's also extremely limited.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 18:42:18 2026
    From Newsgroup: comp.theory

    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes
    absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity
    between P and Q". Necessity applies to propositions. It doesn't hold
    *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean
    something other than that you're really going to have to clarify what
    you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. If a
    truth table contains any symbol other than T or F, you're dealing
    with a three or more valued logic which means you have to completely
    redefine every single logical operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any attempt to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you can't do that, then your use of 'necessary' is completely meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    And there's nothing about the above table which in any way captures
    the meaning of 'necessity' so it's entirely unclear why you want to
    use the □ symbol here. Your '□' doesn't have any relation to
    necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing as
    operator overloading, so you can't take a unary operator and use it
    for some ill-defined binary operation as well. You need a new symbol
    since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal logic
    is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use of
    models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.

    Propositional calculus uses models. It's also extremely limited.

    André


    Are you referring to truth tables as models?
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 17:57:29 2026
    From Newsgroup: comp.theory

    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes
    absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity
    between P and Q". Necessity applies to propositions. It doesn't hold
    *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean
    something other than that you're really going to have to clarify
    what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. If a
    truth table contains any symbol other than T or F, you're dealing
    with a three or more valued logic which means you have to completely
    redefine every single logical operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any attempt to
    explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you can't
    do that, then your use of 'necessary' is completely meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between 'necessary consequence' and mere 'consequence'. The two examples above don't even
    mention the word 'necessary'.

    And there's nothing about the above table which in any way captures
    the meaning of 'necessity' so it's entirely unclear why you want to
    use the □ symbol here. Your '□' doesn't have any relation to
    necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing as
    operator overloading, so you can't take a unary operator and use it
    for some ill-defined binary operation as well. You need a new symbol
    since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal
    logic is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use of
    models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.

    Propositional calculus uses models. It's also extremely limited.

    André


    Are you referring to truth tables as models?

    No.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 19:08:05 2026
    From Newsgroup: comp.theory

    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity
    between P and Q". Necessity applies to propositions. It doesn't
    hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean
    something other than that you're really going to have to clarify
    what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. If
    a truth table contains any symbol other than T or F, you're dealing >>>>> with a three or more valued logic which means you have to
    completely redefine every single logical operator before you can
    proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any attempt to
    explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English.


    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you can't
    do that, then your use of 'necessary' is completely meaningless
    verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between 'necessary consequence' and mere 'consequence'. The two examples above don't even mention the word 'necessary'.

    And there's nothing about the above table which in any way captures >>>>> the meaning of 'necessity' so it's entirely unclear why you want to >>>>> use the □ symbol here. Your '□' doesn't have any relation to
    necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing as
    operator overloading, so you can't take a unary operator and use it >>>>> for some ill-defined binary operation as well. You need a new
    symbol since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal
    logic is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use
    of models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.

    Propositional calculus uses models. It's also extremely limited.

    André


    Are you referring to truth tables as models?

    No.

    André


    Truth Tables ARE Propositional Model Theory
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 18:23:28 2026
    From Newsgroup: comp.theory

    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity
    between P and Q". Necessity applies to propositions. It doesn't
    hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean >>>>>> something other than that you're really going to have to clarify
    what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. If >>>>>> a truth table contains any symbol other than T or F, you're
    dealing with a three or more valued logic which means you have to >>>>>> completely redefine every single logical operator before you can
    proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any attempt
    to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English.


    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither 'impossibly
    false' nor 'impossibly true' are English. In English, 'impossibly x'
    does not mean 'not possible to be x'. 'Impossibly' is an *itensifier*
    with a meaning of extremely. So 'impossibly true' would mean 'extremely
    true', which makes no sense since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you
    can't do that, then your use of 'necessary' is completely
    meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between 'necessary
    consequence' and mere 'consequence'. The two examples above don't even
    mention the word 'necessary'.

    This question was the central point of my post and you have ignored it.
    I maintain that when you use the term 'necessary' your just tossing in a meaningless word for no reason. If you can answer the above question you
    will show me wrong.

    And there's nothing about the above table which in any way
    captures the meaning of 'necessity' so it's entirely unclear why
    you want to use the □ symbol here. Your '□' doesn't have any
    relation to necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing as >>>>>> operator overloading, so you can't take a unary operator and use
    it for some ill-defined binary operation as well. You need a new
    symbol since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal
    logic is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use >>>>>> of models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.

    Propositional calculus uses models. It's also extremely limited.

    André


    Are you referring to truth tables as models?

    No.

    André


    Truth Tables ARE Propositional Model Theory

    No they're not. Truth tables are used to define the basic operators in a truth-functional logic.

    Please evaluate the propositional calculus expression P → Q. Without
    knowing what P or Q stand for you cannot do this. The model tells you
    what P and Q actually mean making it possible to assign a truth value to
    P → Q.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 19:33:02 2026
    From Newsgroup: comp.theory

    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity >>>>>>> between P and Q". Necessity applies to propositions. It doesn't >>>>>>> hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean >>>>>>> something other than that you're really going to have to clarify >>>>>>> what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. >>>>>>> If a truth table contains any symbol other than T or F, you're
    dealing with a three or more valued logic which means you have to >>>>>>> completely redefine every single logical operator before you can >>>>>>> proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any attempt
    to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English.


    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither 'impossibly
    false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    In English, 'impossibly x'
    does not mean 'not possible to be x'. 'Impossibly' is an *itensifier*
    with a meaning of extremely. So 'impossibly true' would mean 'extremely true', which makes no sense since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you
    can't do that, then your use of 'necessary' is completely
    meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between 'necessary
    consequence' and mere 'consequence'. The two examples above don't
    even mention the word 'necessary'.

    This question was the central point of my post and you have ignored it.
    I maintain that when you use the term 'necessary' your just tossing in a meaningless word for no reason. If you can answer the above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    If Q is a necessary consequence of P then
    we are not allowed to infer anything from ~P

    And there's nothing about the above table which in any way
    captures the meaning of 'necessity' so it's entirely unclear why >>>>>>> you want to use the □ symbol here. Your '□' doesn't have any >>>>>>> relation to necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing >>>>>>> as operator overloading, so you can't take a unary operator and >>>>>>> use it for some ill-defined binary operation as well. You need a >>>>>>> new symbol since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal >>>>>>> logic is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making use >>>>>>> of models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.

    Propositional calculus uses models. It's also extremely limited.

    André


    Are you referring to truth tables as models?

    No.

    André


    Truth Tables ARE Propositional Model Theory

    No they're not. Truth tables are used to define the basic operators in a truth-functional logic.

    Please evaluate the propositional calculus expression P → Q. Without knowing what P or Q stand for you cannot do this. The model tells you
    what P and Q actually mean making it possible to assign a truth value to
    P → Q.

    André


    In propositional logic they are only Boolean variables
    with zero additional meaning besides true and false.
    If you think otherwise then cite a source.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 18:43:24 2026
    From Newsgroup: comp.theory

    On 2026-07-04 18:33, olcott wrote:
    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary
    form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete necessity >>>>>>>> between P and Q". Necessity applies to propositions. It doesn't >>>>>>>> hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean >>>>>>>> something other than that you're really going to have to clarify >>>>>>>> what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. >>>>>>>> If a truth table contains any symbol other than T or F, you're >>>>>>>> dealing with a three or more valued logic which means you have >>>>>>>> to completely redefine every single logical operator before you >>>>>>>> can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any attempt >>>>>> to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English.


    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither 'impossibly
    false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    You didn't use the word 'impossible'. You used the word 'impossibly'
    which is a different word. I understand the meaning of both perfectly well.

    In English, 'impossibly x' does not mean 'not possible to be x'.
    'Impossibly' is an *itensifier* with a meaning of extremely. So
    'impossibly true' would mean 'extremely true', which makes no sense
    since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you
    can't do that, then your use of 'necessary' is completely
    meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between 'necessary
    consequence' and mere 'consequence'. The two examples above don't
    even mention the word 'necessary'.

    This question was the central point of my post and you have ignored
    it. I maintain that when you use the term 'necessary' your just
    tossing in a meaningless word for no reason. If you can answer the
    above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    The modal operators don't *have* truth tables anymore than any other quantifier does, and whatever it is you're trying to convey by '□' above applies only to a three-valued logic and certainly has nothing to do
    with necessity.

    If Q is a necessary consequence of P then
    we are not allowed to infer anything from ~P

    Again, you're tossing out the word 'necessary' without any indication
    that it has any particular meaning in your usage. What you write above
    is just as applicable to plain ordinary implication without the word 'necessary. So again I ask, can you give an example where (a) hold true
    but where (b) does not.

    a) Q is a consequence of P
    b) Q is a necessary consequence of P.

    Unless it is possible for the above two statements to have different
    truth values, the word 'necessary' is serving absolutely no purpose.

    In modal logic, P → Q and □(P → Q) mean distinctly different things with distinctly different meanings and these meanings are well-defined within
    that framework. In your usage it is completely unclear what difference,
    if any, holds between the two.

    André

    And there's nothing about the above table which in any way
    captures the meaning of 'necessity' so it's entirely unclear why >>>>>>>> you want to use the □ symbol here. Your '□' doesn't have any >>>>>>>> relation to necessity any more than '→' does above.

    Also note that formal logic is *not* c++. There's no such thing >>>>>>>> as operator overloading, so you can't take a unary operator and >>>>>>>> use it for some ill-defined binary operation as well. You need a >>>>>>>> new symbol since □ is already taken.

    P □ Q makes as much sense as P ¬ Q or P ∀ Q

    So how would you interpret 'necessity' without models?

    I note you didn't answer this. The notion of necessity in modal >>>>>>>> logic is intrinsically tied to model theory.

    How exactly are you defining 'necessity' if you're not making >>>>>>>> use of models?

    André


    Do you know what propositional logic is?
    then that is one way to avoid models.

    Propositional calculus uses models. It's also extremely limited.

    André


    Are you referring to truth tables as models?

    No.

    André


    Truth Tables ARE Propositional Model Theory

    No they're not. Truth tables are used to define the basic operators in
    a truth-functional logic.

    Please evaluate the propositional calculus expression P → Q. Without
    knowing what P or Q stand for you cannot do this. The model tells you
    what P and Q actually mean making it possible to assign a truth value
    to P → Q.

    André


    In propositional logic they are only Boolean variables
    with zero additional meaning besides true and false.
    If you think otherwise then cite a source.

    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 20:18:41 2026
    From Newsgroup: comp.theory

    On 7/4/2026 7:43 PM, André G. Isaak wrote:
    On 2026-07-04 18:33, olcott wrote:
    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary >>>>>>>>>>>>>>>> form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense
    and corrects a fundamental error in the definition of
    valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete
    necessity between P and Q". Necessity applies to propositions. >>>>>>>>> It doesn't hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean >>>>>>>>> something other than that you're really going to have to
    clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued logic. >>>>>>>>> If a truth table contains any symbol other than T or F, you're >>>>>>>>> dealing with a three or more valued logic which means you have >>>>>>>>> to completely redefine every single logical operator before you >>>>>>>>> can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any
    attempt to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English.


    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither 'impossibly
    false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    You didn't use the word 'impossible'. You used the word 'impossibly'
    which is a different word. I understand the meaning of both perfectly well.

    In English, 'impossibly x' does not mean 'not possible to be x'.
    'Impossibly' is an *itensifier* with a meaning of extremely. So
    'impossibly true' would mean 'extremely true', which makes no sense
    since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you >>>>>>> can't do that, then your use of 'necessary' is completely
    meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between
    'necessary consequence' and mere 'consequence'. The two examples
    above don't even mention the word 'necessary'.

    This question was the central point of my post and you have ignored
    it. I maintain that when you use the term 'necessary' your just
    tossing in a meaningless word for no reason. If you can answer the
    above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    The modal operators don't *have* truth tables
    I corrected this stipulative definition below.

    Validity and Soundness
    A deductive argument is said to be valid if and only
    if it takes a form that makes it impossible for the
    premises to be true and the conclusion nevertheless
    to be false. https://iep.utm.edu/val-snd/

    Is corrected to mean
    A deductive argument is said to be valid if and only
    if it takes a form that anything besides true
    premises and true conclusion is invalid.

    P □ Q means P(true) ∧ Q(true) is valid
    everything else is invalid.

    P □ Q
    0 0 0
    0 0 1
    1 0 0
    1 1 1

    I finally said it clearly
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 19:28:28 2026
    From Newsgroup: comp.theory

    On 2026-07-04 19:18, olcott wrote:
    On 7/4/2026 7:43 PM, André G. Isaak wrote:
    On 2026-07-04 18:33, olcott wrote:
    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary >>>>>>>>>>>>>>>>> form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense >>>>>>>>>>>>> and corrects a fundamental error in the definition of >>>>>>>>>>>>> valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete
    necessity between P and Q". Necessity applies to propositions. >>>>>>>>>> It doesn't hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you mean >>>>>>>>>> something other than that you're really going to have to
    clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued
    logic. If a truth table contains any symbol other than T or F, >>>>>>>>>> you're dealing with a three or more valued logic which means >>>>>>>>>> you have to completely redefine every single logical operator >>>>>>>>>> before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any
    attempt to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English.


    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither
    'impossibly false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    You didn't use the word 'impossible'. You used the word 'impossibly'
    which is a different word. I understand the meaning of both perfectly
    well.

    In English, 'impossibly x' does not mean 'not possible to be x'.
    'Impossibly' is an *itensifier* with a meaning of extremely. So
    'impossibly true' would mean 'extremely true', which makes no sense
    since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you >>>>>>>> can't do that, then your use of 'necessary' is completely
    meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between
    'necessary consequence' and mere 'consequence'. The two examples
    above don't even mention the word 'necessary'.

    This question was the central point of my post and you have ignored
    it. I maintain that when you use the term 'necessary' your just
    tossing in a meaningless word for no reason. If you can answer the
    above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    The modal operators don't *have* truth tables
    I corrected this stipulative definition below.

    Your definitions are not coherent.

    Validity and Soundness
    A deductive argument is said to be valid if and only
    if it takes a form that makes it impossible for the
    premises to be true and the conclusion nevertheless
    to be false. https://iep.utm.edu/val-snd/

    Is corrected to mean
    A deductive argument is said to be valid if and only
    if it takes a form that anything besides true
    premises and true conclusion is invalid.

    P □ Q means P(true) ∧ Q(true) is valid
    everything else is invalid.

    P □ Q
    0 0 0
    0 0 1
    1 0 0
    1 1 1

    That's simply the truth table for 'and'. It sheds no light on what it is
    your trying to convey by your use of 'necessity'. And the operator □ is already taken and is not a truth-functional operator so reusing it for something else is just plain stupid.

    And snipping my question doesn't make it go away:

    Can you give an example where (a) hold true but where (b) does not. An
    example from ordinary English is fine.

    a) Q is a consequence of P
    b) Q is a necessary consequence of P.

    If you can't, your use of the term 'necessary' serves absolutely no purpose.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 21:17:22 2026
    From Newsgroup: comp.theory

    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    On 2026-07-04 19:18, olcott wrote:
    On 7/4/2026 7:43 PM, André G. Isaak wrote:
    On 2026-07-04 18:33, olcott wrote:
    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary >>>>>>>>>>>>>>>>>> form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense >>>>>>>>>>>>>> and corrects a fundamental error in the definition of >>>>>>>>>>>>>> valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete
    necessity between P and Q". Necessity applies to
    propositions. It doesn't hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you >>>>>>>>>>> mean something other than that you're really going to have to >>>>>>>>>>> clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued >>>>>>>>>>> logic. If a truth table contains any symbol other than T or >>>>>>>>>>> F, you're dealing with a three or more valued logic which >>>>>>>>>>> means you have to completely redefine every single logical >>>>>>>>>>> operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any
    attempt to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English. >>>>>>>

    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither
    'impossibly false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    You didn't use the word 'impossible'. You used the word 'impossibly'
    which is a different word. I understand the meaning of both perfectly
    well.

    In English, 'impossibly x' does not mean 'not possible to be x'.
    'Impossibly' is an *itensifier* with a meaning of extremely. So
    'impossibly true' would mean 'extremely true', which makes no sense >>>>> since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you >>>>>>>>> can't do that, then your use of 'necessary' is completely
    meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between
    'necessary consequence' and mere 'consequence'. The two examples >>>>>>> above don't even mention the word 'necessary'.

    This question was the central point of my post and you have ignored >>>>> it. I maintain that when you use the term 'necessary' your just
    tossing in a meaningless word for no reason. If you can answer the
    above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    The modal operators don't *have* truth tables
    I corrected this stipulative definition below.

    Your definitions are not coherent.

    Validity and Soundness
    A deductive argument is said to be valid if and only
    if it takes a form that makes it impossible for the
    premises to be true and the conclusion nevertheless
    to be false. https://iep.utm.edu/val-snd/

    Is corrected to mean
    A deductive argument is said to be valid if and only
    if it takes a form that anything besides true
    premises and true conclusion is invalid.

    P □ Q means P(true) ∧ Q(true) is valid
    everything else is invalid.

    P □ Q
    0 0 0
    0 0 1
    1 0 0
    1 1 1

    That's simply the truth table for 'and'. It sheds no light on what it is your trying to convey by your use of 'necessity'. And the operator □ is already taken and is not a truth-functional operator so reusing it for something else is just plain stupid.


    Dogs are cats → Monkeys have wings
    ¬(Dogs are cats □ Monkeys have wings)
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 20:22:27 2026
    From Newsgroup: comp.theory

    On 2026-07-04 20:17, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    On 2026-07-04 19:18, olcott wrote:
    On 7/4/2026 7:43 PM, André G. Isaak wrote:
    On 2026-07-04 18:33, olcott wrote:
    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary >>>>>>>>>>>>>>>>>>> form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense >>>>>>>>>>>>>>> and corrects a fundamental error in the definition of >>>>>>>>>>>>>>> valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete >>>>>>>>>>>> necessity between P and Q". Necessity applies to
    propositions. It doesn't hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you >>>>>>>>>>>> mean something other than that you're really going to have >>>>>>>>>>>> to clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued >>>>>>>>>>>> logic. If a truth table contains any symbol other than T or >>>>>>>>>>>> F, you're dealing with a three or more valued logic which >>>>>>>>>>>> means you have to completely redefine every single logical >>>>>>>>>>>> operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any >>>>>>>>>> attempt to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English. >>>>>>>>

    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither
    'impossibly false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    You didn't use the word 'impossible'. You used the word 'impossibly'
    which is a different word. I understand the meaning of both
    perfectly well.

    In English, 'impossibly x' does not mean 'not possible to be x'.
    'Impossibly' is an *itensifier* with a meaning of extremely. So
    'impossibly true' would mean 'extremely true', which makes no
    sense since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If >>>>>>>>>> you can't do that, then your use of 'necessary' is completely >>>>>>>>>> meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between
    'necessary consequence' and mere 'consequence'. The two examples >>>>>>>> above don't even mention the word 'necessary'.

    This question was the central point of my post and you have
    ignored it. I maintain that when you use the term 'necessary' your >>>>>> just tossing in a meaningless word for no reason. If you can
    answer the above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    The modal operators don't *have* truth tables
    I corrected this stipulative definition below.

    Your definitions are not coherent.

    Validity and Soundness
    A deductive argument is said to be valid if and only
    if it takes a form that makes it impossible for the
    premises to be true and the conclusion nevertheless
    to be false. https://iep.utm.edu/val-snd/

    Is corrected to mean
    A deductive argument is said to be valid if and only
    if it takes a form that anything besides true
    premises and true conclusion is invalid.

    P □ Q means P(true) ∧ Q(true) is valid
    everything else is invalid.

    P □ Q
    0 0 0
    0 0 1
    1 0 0
    1 1 1

    That's simply the truth table for 'and'. It sheds no light on what it
    is your trying to convey by your use of 'necessity'. And the operator
    □ is already taken and is not a truth-functional operator so reusing
    it for something else is just plain stupid.


    Dogs are cats → Monkeys have wings
    ¬(Dogs are cats □ Monkeys have wings)

    I have no idea what point you're trying to make with this example. The
    truth table you gave for your poorly named □ is just the truth table for and. Giving it a different symbol achieves absolutely nothing. It
    certainly doesn't magically change the meaning of 'and' to anything
    involving the word 'necessary'.

    Playing around with truth tables isn't going to get you anywhere.
    Standard boolean logic is already truth-functionally complete, so there absolutely no new truth table you can produce that can't already be
    expressed using standard operators.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 21:29:58 2026
    From Newsgroup: comp.theory

    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    On 2026-07-04 19:18, olcott wrote:
    On 7/4/2026 7:43 PM, André G. Isaak wrote:
    On 2026-07-04 18:33, olcott wrote:
    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary >>>>>>>>>>>>>>>>>> form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense >>>>>>>>>>>>>> and corrects a fundamental error in the definition of >>>>>>>>>>>>>> valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete
    necessity between P and Q". Necessity applies to
    propositions. It doesn't hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you >>>>>>>>>>> mean something other than that you're really going to have to >>>>>>>>>>> clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued >>>>>>>>>>> logic. If a truth table contains any symbol other than T or >>>>>>>>>>> F, you're dealing with a three or more valued logic which >>>>>>>>>>> means you have to completely redefine every single logical >>>>>>>>>>> operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any
    attempt to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English. >>>>>>>

    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither
    'impossibly false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    You didn't use the word 'impossible'. You used the word 'impossibly'
    which is a different word. I understand the meaning of both perfectly
    well.

    In English, 'impossibly x' does not mean 'not possible to be x'.
    'Impossibly' is an *itensifier* with a meaning of extremely. So
    'impossibly true' would mean 'extremely true', which makes no sense >>>>> since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If you >>>>>>>>> can't do that, then your use of 'necessary' is completely
    meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between
    'necessary consequence' and mere 'consequence'. The two examples >>>>>>> above don't even mention the word 'necessary'.

    This question was the central point of my post and you have ignored >>>>> it. I maintain that when you use the term 'necessary' your just
    tossing in a meaningless word for no reason. If you can answer the
    above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    The modal operators don't *have* truth tables
    I corrected this stipulative definition below.

    Your definitions are not coherent.

    Validity and Soundness
    A deductive argument is said to be valid if and only
    if it takes a form that makes it impossible for the
    premises to be true and the conclusion nevertheless
    to be false. https://iep.utm.edu/val-snd/

    Is corrected to mean
    A deductive argument is said to be valid if and only
    if it takes a form that anything besides true
    premises and true conclusion is invalid.

    P □ Q means P(true) ∧ Q(true) is valid
    everything else is invalid.

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1

    That's simply the truth table for 'and'.

    It had a typo

    It sheds no light on what it is
    your trying to convey by your use of 'necessity'. And the operator □ is already taken and is not a truth-functional operator so reusing it for something else is just plain stupid.

    And snipping my question doesn't make it go away:

    Can you give an example where (a) hold true but where (b) does not. An example from ordinary English is fine.

    a) Q is a consequence of P
    b) Q is a necessary consequence of P.

    If you can't, your use of the term 'necessary' serves absolutely no
    purpose.

    André

    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 20:50:15 2026
    From Newsgroup: comp.theory

    On 2026-07-04 20:29, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    On 2026-07-04 19:18, olcott wrote:
    On 7/4/2026 7:43 PM, André G. Isaak wrote:
    On 2026-07-04 18:33, olcott wrote:
    On 7/4/2026 7:23 PM, André G. Isaak wrote:
    On 2026-07-04 18:08, olcott wrote:
    On 7/4/2026 6:57 PM, André G. Isaak wrote:
    On 2026-07-04 17:42, olcott wrote:
    On 7/4/2026 5:11 PM, André G. Isaak wrote:
    On 2026-07-04 15:36, olcott wrote:
    On 7/4/2026 4:29 PM, André G. Isaak wrote:
    On 2026-07-04 14:58, olcott wrote:
    On 7/4/2026 11:59 AM, André G. Isaak wrote:
    On 2026-07-04 10:44, olcott wrote:
    On 7/4/2026 10:08 AM, André G. Isaak wrote:
    On 2026-07-04 07:21, olcott wrote:
    On 7/4/2026 1:47 AM, Mikko wrote:
    On 03/07/2026 18:04, olcott wrote:

    P ⇒ Q
    P → Q
    P ⊃ Q

    are all abolished and replaced with the binary >>>>>>>>>>>>>>>>>>> form of logical necessity: P □ Q

    There is no 'binary form of logical necessity.

    That is why I just created one.

    But you didn't define it.

    □ is a unary operator and an expression like P □ Q makes >>>>>>>>>>>>>>>> absolutely no sense.


    Q is a necessary consequence of P makes perfect sense >>>>>>>>>>>>>>> and corrects a fundamental error in the definition of >>>>>>>>>>>>>>> valid deductive inference.

    That would normally be written as □(P → Q),

    That does not perfectly preserve the complete
    necessity between P and Q.

    What on earth does it mean for there to be a "complete >>>>>>>>>>>> necessity between P and Q". Necessity applies to
    propositions. It doesn't hold *between* things.

    □(P → Q) means that Q is necessarily implied by P. If you >>>>>>>>>>>> mean something other than that you're really going to have >>>>>>>>>>>> to clarify what you mean.

    P □ Q   P → Q
    0 ? 0   0 1 0
    0 ? 1   0 1 1
    1 0 0   1 0 0
    1 1 1   1 1 1
    Q is a necessary consequence of P
    is the same as English If P then Q
    (a) false when P is true and Q is false
    (b) true  when P is true and Q is true
    (c) otherwise does not have a truth value.

    So again your veering into the territory of three-valued >>>>>>>>>>>> logic. If a truth table contains any symbol other than T or >>>>>>>>>>>> F, you're dealing with a three or more valued logic which >>>>>>>>>>>> means you have to completely redefine every single logical >>>>>>>>>>>> operator before you can proceed.


    The English if P then Q only actually tells you
    P(true) then necessarily Q(true)
    Q(false) then necessarily P(false)
    IT DOES NOT TELL YOU MORE THAN THIS AND
    IT IS STUPID MISTAKE TO ASSUME OTHERWISE
    THE WAY THAT IMPLICATION STUPIDLY DOES.

    You're introducing the word 'necessarily' here without any >>>>>>>>>> attempt to explain what is meant by this (by you).


    I always use the ordinary English meaning.
    If P is true then Q is impossibly false.
    If Q is false the P is impossibly true.

    'impossibly false' and 'impossibly true' aren't ordinary English. >>>>>>>>

    Tell me whether or not the numerical square root
    of a dead chicken can exist and why or why not.
    You must not start with any numerical value such
    as the weight of the dead chicken. You are only
    allowed to use its actual dead body.

    What does the above have to do with my claim that neither
    'impossibly false' nor 'impossibly true' are English.

    You did not seem to understand the meaning of the word impossible.

    You didn't use the word 'impossible'. You used the word 'impossibly'
    which is a different word. I understand the meaning of both
    perfectly well.

    In English, 'impossibly x' does not mean 'not possible to be x'.
    'Impossibly' is an *itensifier* with a meaning of extremely. So
    'impossibly true' would mean 'extremely true', which makes no
    sense since true is not a gradient concept.

    What is the difference between

    a) Q is a necessary consequence of P.
    b) Q is a consequence of P

    Give an example where b holds true but where a is false. If >>>>>>>>>> you can't do that, then your use of 'necessary' is completely >>>>>>>>>> meaningless verbiage.


    If someone smacks you in the face then
    you were hit in the face.

    If you were NOT hit in the face then
    someone did not smack you in the face.

    I asked for an example illustrating the different between
    'necessary consequence' and mere 'consequence'. The two examples >>>>>>>> above don't even mention the word 'necessary'.

    This question was the central point of my post and you have
    ignored it. I maintain that when you use the term 'necessary' your >>>>>> just tossing in a meaningless word for no reason. If you can
    answer the above question you will show me wrong.


    The modal operators □ and ◊

    P □ Q --- P → Q
    0 ? 0 --- 0 1 0
    0 ? 1 --- 0 1 1
    1 0 0 --- 1 0 0
    1 1 1 --- 1 1 1

    The modal operators don't *have* truth tables
    I corrected this stipulative definition below.

    Your definitions are not coherent.

    Validity and Soundness
    A deductive argument is said to be valid if and only
    if it takes a form that makes it impossible for the
    premises to be true and the conclusion nevertheless
    to be false. https://iep.utm.edu/val-snd/

    Is corrected to mean
    A deductive argument is said to be valid if and only
    if it takes a form that anything besides true
    premises and true conclusion is invalid.

    P □ Q means P(true) ∧ Q(true) is valid
    everything else is invalid.

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1

    That's simply the truth table for 'and'.

    It had a typo

    Don't correct it in the quoted text. By doing so you're claiming that
    the above is what you originally wrote which is simply dishonest.

    Now what you've got isn't even a valid truth-table since it has no value
    for when P is 0 and Q is 1. Instead you've got two entries for when both
    are 0.

    It sheds no light on what it is your trying to convey by your use of
    'necessity'. And the operator □ is already taken and is not a
    truth-functional operator so reusing it for something else is just
    plain stupid.

    And snipping my question doesn't make it go away:

    Can you give an example where (a) hold true but where (b) does not. An
    example from ordinary English is fine.

    a) Q is a consequence of P
    b) Q is a necessary consequence of P.

    If you can't, your use of the term 'necessary' serves absolutely no
    purpose.

    Still no answer to the above?

    If you're actually interesting in explaining what it is that you mean by 'necessary' you would answer the above.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 22:17:01 2026
    From Newsgroup: comp.theory

    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    Q is a necessary consequence of P

    seems best handled by
    https://en.wikipedia.org/wiki/Relevance_logic
    or Parry's Entailment Logic

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1

    Changes the notion of valid inference too much.
    I myself simply leap all the way to the end and
    say that the full natural language semantic meaning
    must be encoded for both P and Q such that P ⊢ Q
    by semantic entailment specified syntactically.
    This is accomplished in a language such as CycL. https://en.wikipedia.org/wiki/CycL
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 21:23:44 2026
    From Newsgroup: comp.theory

    On 2026-07-04 21:17, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    Q is a necessary consequence of P

    seems best handled by
    https://en.wikipedia.org/wiki/Relevance_logic
    or Parry's Entailment Logic

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1


    That's *not* a valid truth table. It has no entry for P = 0 and Q = 1.

    And Parry is working in relevance logic. He doesn't deal with modal expressions like 'necessary'.

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 22:45:21 2026
    From Newsgroup: comp.theory

    On 7/4/2026 10:23 PM, André G. Isaak wrote:
    On 2026-07-04 21:17, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    Q is a necessary consequence of P

    seems best handled by
    https://en.wikipedia.org/wiki/Relevance_logic
    or Parry's Entailment Logic

    P Q □
    0 0 0
    0 1 0
    1 0 0
    1 1 1


    That's *not* a valid truth table. It has no entry for P = 0 and Q = 1.

    And Parry is working in relevance logic. He doesn't deal with modal expressions like 'necessary'.

    André


    You did not bother to notice that I just rejected
    that whole idea in the part that you ignored.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 21:52:04 2026
    From Newsgroup: comp.theory

    On 2026-07-04 21:17, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    Q is a necessary consequence of P

    seems best handled by
    https://en.wikipedia.org/wiki/Relevance_logic
    or Parry's Entailment Logic

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1

    Changes the notion of valid inference too much.

    It doesn't change anything. It's simply invalid since its not a
    well-formed truth table.

    I myself simply leap all the way to the end and
    say that the full natural language semantic meaning
    must be encoded for both P and Q such that P ⊢ Q
    by semantic entailment specified syntactically.
    This is accomplished in a language such as CycL. https://en.wikipedia.org/wiki/CycL

    The above sheds no light on anything. In particular it doesn't clarify
    what you think the difference between entailment and necessary
    entailment is which is the question I have been trying to get you to
    address.
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sat Jul 4 23:05:14 2026
    From Newsgroup: comp.theory

    On 7/4/2026 10:52 PM, André G. Isaak wrote:
    On 2026-07-04 21:17, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    Q is a necessary consequence of P

    seems best handled by
    https://en.wikipedia.org/wiki/Relevance_logic
    or Parry's Entailment Logic

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1

    Changes the notion of valid inference too much.

    It doesn't change anything. It's simply invalid since its not a well-
    formed truth table.

    I myself simply leap all the way to the end and
    say that the full natural language semantic meaning
    must be encoded for both P and Q such that P ⊢ Q
    by semantic entailment specified syntactically.
    This is accomplished in a language such as CycL.
    https://en.wikipedia.org/wiki/CycL

    The above sheds no light on anything. In particular it doesn't clarify
    what you think the difference between entailment and necessary
    entailment is which is the question I have been trying to get you to address.



    *This says the whole thing better*
    P ⊢ Q means: syntactic derivation implements semantic entailment encoded
    in the language. The inference rules are syntactic rules that realize
    semantic entailment. These are the only allowed inference steps. The entailment rules depend on the represented domain.

    Dogs are cats ⊢ Monkeys have wings // rejected
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From =?UTF-8?B?QW5kcsOpIEcuIElzYWFr?=@agisaak@gm.invalid to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sun Jul 5 14:40:47 2026
    From Newsgroup: comp.theory

    On 2026-07-04 22:05, olcott wrote:
    On 7/4/2026 10:52 PM, André G. Isaak wrote:
    On 2026-07-04 21:17, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    Q is a necessary consequence of P

    seems best handled by
    https://en.wikipedia.org/wiki/Relevance_logic
    or Parry's Entailment Logic

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1

    Changes the notion of valid inference too much.

    It doesn't change anything. It's simply invalid since its not a well-
    formed truth table.

    I myself simply leap all the way to the end and
    say that the full natural language semantic meaning
    must be encoded for both P and Q such that P ⊢ Q
    by semantic entailment specified syntactically.
    This is accomplished in a language such as CycL.
    https://en.wikipedia.org/wiki/CycL

    The above sheds no light on anything. In particular it doesn't clarify
    what you think the difference between entailment and necessary
    entailment is which is the question I have been trying to get you to
    address.



    *This says the whole thing better*
    P ⊢ Q means: syntactic derivation implements semantic entailment encoded in the language. The inference rules are syntactic rules that realize semantic entailment. These are the only allowed inference steps. The entailment rules depend on the represented domain.

    Dogs are cats ⊢ Monkeys have wings // rejected

    The topic under discussion was Q, which contains neither dogs, cats,
    monkeys, or wings.

    Why don't you illustrate your claim with an actual example from
    arithmetic. Say, for example 9 × 5 = 45. What exactly would be the
    "semantic entailments encoded in the language" involved here?

    André
    --
    To email remove 'invalid' & replace 'gm' with well known Google mail
    service.

    --- Synchronet 3.22a-Linux NewsLink 1.2
  • From olcott@polcott333@gmail.com to sci.logic,comp.theory,sci.math,comp.ai.philosophy,alt.philosophy on Sun Jul 5 15:51:56 2026
    From Newsgroup: comp.theory

    On 7/5/2026 3:40 PM, André G. Isaak wrote:
    On 2026-07-04 22:05, olcott wrote:
    On 7/4/2026 10:52 PM, André G. Isaak wrote:
    On 2026-07-04 21:17, olcott wrote:
    On 7/4/2026 8:28 PM, André G. Isaak wrote:
    Q is a necessary consequence of P

    seems best handled by
    https://en.wikipedia.org/wiki/Relevance_logic
    or Parry's Entailment Logic

    P □ Q
    0 0 0
    0 0 0
    1 0 0
    1 1 1

    Changes the notion of valid inference too much.

    It doesn't change anything. It's simply invalid since its not a well-
    formed truth table.

    I myself simply leap all the way to the end and
    say that the full natural language semantic meaning
    must be encoded for both P and Q such that P ⊢ Q
    by semantic entailment specified syntactically.
    This is accomplished in a language such as CycL.
    https://en.wikipedia.org/wiki/CycL

    The above sheds no light on anything. In particular it doesn't
    clarify what you think the difference between entailment and
    necessary entailment is which is the question I have been trying to
    get you to address.



    *This says the whole thing better*
    P ⊢ Q means: syntactic derivation implements semantic entailment
    encoded in the language. The inference rules are syntactic rules that
    realize semantic entailment. These are the only allowed inference
    steps. The entailment rules depend on the represented domain.

    Dogs are cats ⊢ Monkeys have wings // rejected

    The topic under discussion was Q, which contains neither dogs, cats, monkeys, or wings.


    No it is: William T. Parry gets rid of Disjunction introduction

    Why don't you illustrate your claim with an actual example from
    arithmetic. Say, for example 9 × 5 = 45. What exactly would be the "semantic entailments encoded in the language" involved here?

    André


    PTS takes the inference steps of PA as semantic
    entailment in that case.
    --
    Copyright 2026 Olcott

    My 28 year goal has been to make
    "true on the basis of meaning expressed in language"
    reliably computable for the entire body of knowledge.
    The complete structure of this system is now defined.

    The entire body of knowledge expressed in language is
    comprised of two types of relations between finite strings:
    (a) *Axioms* Expressions of language that are stipulated to be true.

    My system bridges the analytic/synthetic distinction by
    expressly encoding all empirical "atomic facts" in a formal
    language such as CycL of the Cyc project.

    (b) *Inference Rules* Expressions of language that are semantically
    entailed syntactically from (a) and/or (b).
    --- Synchronet 3.22a-Linux NewsLink 1.2