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|    sci.logic    |    Logic -- math, philosophy & computationa    |    262,912 messages    |
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|    Message 262,314 of 262,912    |
|    Tristan Wibberley to olcott    |
|    Re: have we been misusing incompleteness    |
|    02 Jan 26 08:15:22    |
      XPost: comp.theory, sci.math       From: tristan.wibberley+netnews2@alumni.manchester.ac.uk              On 02/01/2026 03:26, olcott wrote:       > On 1/1/2026 8:38 PM, olcott wrote:       >> On 1/1/2026 8:25 PM, Richard Damon wrote:       >>> On 1/1/26 9:07 PM, olcott wrote:       >>>> On 1/1/2026 4:12 PM, Tristan Wibberley wrote:       >>>>> On 31/12/2025 23:27, Richard Damon wrote:       >>>>>       >>>>>> So, how do you think you can prove it in F?       >>>>>       >>>>> What does "F" refer to?       >>>>>       >>>>       >>>> F ⊢ G_F ↔ ¬Prov_F(⌜G_F⌝)       >>>> F proves that: G_F is equivalent to G_F is not provable in F       >>>> https://plato.stanford.edu/entries/goedel-incompleteness/#FirIncTheCom       >>>>       >>>> ∃G ∈ WFF(F) (G ↔ (F ⊬ G))       >>>> There exists a G in F that is logically       >>>> equivalent to its own unprovability in F       >>>>       >>>> ∃G ∈ WFF(F) (G := (F ⊬ G))       >>>> There exists a G in F that asserts its own unprovability in F       >>>>       >>>> The proof of G in F would seem to require a sequence       >>>> of inference steps in F that prove that they themselves       >>>> do not exist.       >>>>       >>>>       >>>       >>> But that isn't what G is in the proof, so you are just using a bad       >>> reference.       >>>       >>       >> That you do not know exactly how semantics works in       >> linguistics (making sure to ignore all context) is       >> not my mistake. The reason that Ludwig Wittgenstein       >> was never understood is that none of his detractors       >> understood how language itself really works. Not       >> knowing how language really works results in       >> undetected muddled thinking.       >>       >> ...We are therefore confronted with a proposition which       >> asserts its own unprovability. 15 … (Gödel 1931:40-41)       >>       >> G asserts its own unprovability.       >> Is what the above means semantically.       >>       >> The proof of G does semantically entail a sequence       >> of inference steps that prove that they themselves       >> do not exist.       >>       >       > Ludwig Wittgenstein       >       > 8. I imagine someone asking my advice; he says:       > "I have constructed a proposition (1 will use       > 'P' to designate it) in Russell's symbolism,       > and by means of certain definitions and       > transformations it can be so interpreted that       > it says: 'P is not provable in Russell's system'.              False. He did not do that; he tried to do so then hallucinated that he       succeeded. A contradiction follows from the negation of my       characterisation of his actions and so from the truth of the proposition       that he defined P so. That definitional proposition follows from the       axioms of inconsistent systems and not from those of useful consistent       ones. Typically it /is/ an axiom of inconsistent systems and not of       consistent ones.                     --       Tristan Wibberley              The message body is Copyright (C) 2025 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.              --- SoupGate-DOS v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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