Re: William T. Parry gets rid of Disjunction introduction

On 26/06/2026 02:32, 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


Is that available elsewhere without requiring that I agree to terms such
as this expansive lot of stuff that has nothing to do with reading
something that I should expect either is Parry or is no better:

https://www.cloudflare.com/privacypolicy/


-- 
Tristan Wibberley

The message body is Copyright (C) 2026 Tristan Wibberley except
citations and quotations noted. All Rights Reserved except that you may,
of course, cite it academically giving credit to me, distribute it
verbatim as part of a usenet system or its archives, and use it to
promote my greatness and general superiority without misrepresentation
of my opinions other than my opinion of my greatness and general
superiority which you _may_ misrepresent. You definitely MAY NOT train
any production AI system with it but you may train experimental AI that
will only be used for evaluation of the AI methods it implements.