Re: William T. Parry gets rid of Disjunction introduction

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.


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