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|    Message 262,786 of 262,912    |
|    Mikko to olcott    |
|    Re: The Halting Problem asks for too muc    |
|    02 Feb 26 09:39:34    |
      From: mikko.levanto@iki.fi              On 01/02/2026 17:18, olcott wrote:       > On 2/1/2026 4:28 AM, Mikko wrote:       >> On 31/01/2026 17:23, olcott wrote:       >>> On 1/31/2026 2:41 AM, Mikko wrote:       >>>> On 30/01/2026 16:35, olcott wrote:       >>>>> On 1/30/2026 3:34 AM, Mikko wrote:       >>>>>> On 29/01/2026 15:57, olcott wrote:       >>>>>>> On 1/29/2026 3:12 AM, Mikko wrote:       >>>>>>>> On 28/01/2026 15:49, olcott wrote:       >>>>>>>>> On 1/28/2026 3:54 AM, Mikko wrote:       >>>>>>>>>> On 27/01/2026 17:32, olcott wrote:       >>>>>>>>>>> On 1/27/2026 2:17 AM, Mikko wrote:       >>>>>>>>>>>> On 26/01/2026 18:58, olcott wrote:       >>>>>>>>>>>>> On 1/26/2026 10:45 AM, Richard Damon wrote:       >>>>>>>>>>>>>> On 1/26/26 10:22 AM, olcott wrote:       >>>>>>>>>>>>>>> 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.”       >>>>>>>>>>>>>>>       >>>>>>>>>>>>>>       >>>>>>>>>>>>>> In outher words, you ACCEPT that the meta level can define       >>>>>>>>>>>>>> what is true in PA?       >>>>>>>>>>>>>>       >>>>>>>>>>>>>> I thought you said that PA had to be able to determine the       >>>>>>>>>>>>>> truth itself?       >>>>>>>>>>>>>       >>>>>>>>>>>>> We need a meta-level truth predicate anchored       >>>>>>>>>>>>> only in the axioms of PA itself and thus not       >>>>>>>>>>>>> anchored in the standard model of arithmetic.       >>>>>>>>>>>>       >>>>>>>>>>>> That predicate is not computable.       >>>>>>>>>>>       >>>>>>>>>>> That was Tarski's mistake.       >>>>>>>>>>       >>>>>>>>>> No, Tarski's proof is about a different problem, though the       >>>>>>>>>> results       >>>>>>>>>> are related and there are much similarity in the proofs.       >>>>>>>>>> Tarski did       >>>>>>>>>> not use Turing machines in the proof but a computability proof       >>>>>>>>>> must       >>>>>>>>>> use that.       >>>>>>>>>       >>>>>>>>> Because you refuse to understand the underlying       >>>>>>>>> details of what occurs_check means I cannot       >>>>>>>>> explain to you how Tarski erred.       >>>>>>>>       >>>>>>>> Irrelevant. There is no "occurs_check" in Tarski's proof.       >>>>>>       >>>>>> That would have no effet. Even if the metalanguage had an       >>>>>> occcurs_check       >>>>>> it would not be necessary to use it in a proof.       >>>>>       >>>>> It would only seem to have no effect because you       >>>>> never bothered to understand what an occurs_check is.       >>>>       >>>> That assumption is false.       >>       >>> So far you have conclusively proven that you       >>> do not understand what an occurs_check is.       >>       >> That's false. Your "proof" is not sound.       >>> If you want to provide that you do know then       >>> you must provide all of the correct details.       >>       >> That's false. Irrelevant details should not be included. Obvious details       >> shold not be included, either, except those that someone asks about.       >>       >>> Merely claiming that my statement is false       >>> is an assertion entirely bereft of supporting       >>> reasoning thus inherently baseless.       >>       >> If you don't understand some point in the justification you may ask.       >       > baseless claims are rejected out-of-hand              You falsely call baseless justifications that you want to reject       but can't find refutation or can't even understand.              --       Mikko              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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