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|    Message 262,774 of 262,912    |
|    olcott to Mikko    |
|    Re: The Halting Problem asks for too muc    |
|    01 Feb 26 09:18:03    |
      From: polcott333@gmail.com              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              >>>> Truth is computable because “meaningful sentence”       >>>> is defined as “sentence with a well-founded       >>>> justification tree,” and evaluating any well-founded       >>>> tree always terminates. Anything else isn’t truth-apt.       >>>       >>> That "bcause" is wrong. Whether a sentence has a well-founded       >>> justifiation tree is not computable, especially for arithmetic       >>> sentences.       >>       >> My one half page of text explaining all of the key details       >> of my 28 years of work was completely validated by five       >> different LLM systems. proof theoretic semantics is correct       >> model theoretic semantics is profoundly wrong-headed.       >       > That "proof theoretic semantics is correct model theoretic semantics"       > may indeed be profoundly wrong-headed but there is another possibility       > that you just don't understand it.       >       >> Your ignorance of the details of well-founded proof theoretic       >> semantics makes your rebuttal baseless.       >       > No, that does not follow.       >       >>> But that does not alter the fact that an existence or non-existence       >>> of a metalanguage feature that is not present in the justification       >>> tree is irrelevant.       >       >> An existence or non-existence of a metalanguage feature       >> is entirely anchored in a totally wrong-headed notion.       >       > It does not matter where sometihing irrelevant is anchored.       >       >> The only way that this can be seen is to become an expert       >> in well-founded proof theoretic semantics.       >       > No reason to belive that.       >                            [continued in next message]              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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