Re: William T. Parry gets rid of Disjunction introduction

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.
>>
> 
>