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|    Message 262,736 of 262,912    |
|    olcott to Mikko    |
|    Re: The Halting Problem asks for too muc    |
|    26 Jan 26 09:22:01    |
      XPost: comp.theory, sci.math       From: polcott333@gmail.com              On 1/26/2026 6:55 AM, Mikko wrote:       > On 25/01/2026 15:30, olcott wrote:       >> On 1/25/2026 5:24 AM, Mikko wrote:       >>> On 24/01/2026 16:18, olcott wrote:       >>>> On 1/24/2026 2:23 AM, Mikko wrote:       >>>>> On 22/01/2026 18:47, olcott wrote:       >>>>>> On 1/22/2026 2:21 AM, Mikko wrote:       >>>>>       >>>>>>> Anyway, what can be provven that way is true aboout PA. You can deny       >>>>>>> the proof but you cannot perform what is meta-provably impossible.       >>>>>       >>>>>> The meta-proof does not exist in the axioms of PA       >>>>>> and that is the reason why an external truth in       >>>>>> an external model cannot be proved internally in PA.       >>>>>> All of these years it was only a mere conflation       >>>>>> error.       >>>>>       >>>>> It is perfectly clear which is which. But every proof in PA is also       >>>>> a proof in Gödel's metatheory.       >>>>       >>>> ∀x ∈ PA ( True(PA, x) ≡ PA ⊢ x )       >>>> ∀x ∈ PA ( False(PA, x) ≡ PA ⊢ ¬x )       >>>> ∀x ∈ PA ( ¬WellFounded(PA, x) ≡       >>>> (¬True(PA, x) ∧ (¬False(PA, x)))       >>>       >>> Those sentences don't mean anything without specificantions of a       >>> language and a theory that gives them some meaning.       >>       >> In other word you do not understand standard notational       >> conventions that define True for PA as provable from the       >> axioms of PA and False for PA as refutable from the axioms       >> of PA.       >       > There are no notational convention that defines True, False, and       > WellFounded with two arguments. And you did not specify in which       > context your sentences are true or otherwise relevant.       >              “x is a single finite string representing       a PA‑formula, such as ‘2 + 3 = 5’.       True(PA, x), False(PA, x), and WellFounded(PA, x)       are meta‑level unary predicates classifying       that formula by its provability in PA.”              --       Copyright 2026 Olcott |
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