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From: dbush <dbush.mobile@gmail.com>
Newsgroups: sci.logic
Subject: Re: The key undecidable instance that I know about
Date: Sun, 9 Mar 2025 13:26:52 -0400
Organization: A noiseless patient Spider
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On 3/9/2025 1:15 PM, olcott wrote:
> Is the Liar Paradox True or False?
> 
> LP := ~True(LP)
> 
> ?- LP = not(true(LP)).
> LP = not(true(LP)).
> 
> ?- unify_with_occurs_check(LP, not(true(LP))).
> false.
> 
> Its infinitely recursive structure makes it neither true nor false.
> 

Nice try making a new post to dishonestly dodge your false claim:

On 3/9/2025 12:34 PM, olcott wrote:
 > It turns out that all of the undecidable cases
 > that I know about have no correct yes/no answer.

When you know of this one:

Does algorithm X with input Y halt when run directly for all X and Y?

But no algorithm exists to compute it.

Your above claim is also a category error, as an undecidable problem has 
a valid yes or no answer in all cases as a prerequisite.