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|    comp.ai.philosophy    |    Perhaps we should ask SkyNet about this    |    59,235 messages    |
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|    Message 58,392 of 59,235    |
|    olcott to All    |
|    Making True(Language L, Expression E) al    |
|    21 Nov 25 09:09:37    |
      [continued from previous message]              >> No. I'm not sure what you mean by "a 'satisfactory' problem" because       >       > /A number which is a description number of a circle-free machine will be       > called a satisfactory number. In §8 it is shown that there can be no       > general process for determining whether a given number is satisfactory       > or not/ [Tur36 p241]       >       > after turing spends §1-§7 defining turing machine, §8 is where he proves       > the "halting theorem" as you say. in that proof he's really proving       > there's no way to prove a number "satisfactory" or more technically       > "circle-free"       >       > big miss there buddy, the "satisfactory" paradox (inability to build a       > general decider for "satisfactory" numbers) he describes §8 (on p247) in       > is literally keystone contradiction he bases the rest of his undecidable       > proof       >       >> Turing uses the term "satisfactory" only in relation to numbers.       >> However, he is not supporting Godel's incompleteness theorem, he is       >       > he is 100% supporting godel's result       >       > /If the negation of what Godel has shown had been proved, i.e. if, for       > each U, either U or —U is provable, then we should have an immediate       > solution of the Entscheidungsproblem. For we can invent a machine H       > which will prove consecutively all provable formulae. Sooner or later H       > will reach either U or —U. If it reaches U, then we know that U is       > provable. If it reaches —U, then, since K is consistent (Hilbert and       > Ackermann, p. 65), we know that U is not provable/ [Tur36 p259]       >       > what he's doing is saying that if godel had proven otherwise (to       > incompleteness) then there'd be some machine which would prove all       > provable formulae       >       > because of this there must be some method to ensure such isn't       > construct-able, and ultimately §11 is tying such a machine to the       > previously disproveb notion (of §8) that a decider D that could       > determine whether a given number is satisfactory:       >       > /We are now in a position to show that the Entscheidungsproblem cannot       > be solved. Let us suppose the contrary. Then there is a general       > (mechanical) process for determining whether Un(𝓜 ) is provable. By       > Lemmas 1 and 2, this implies that there is a process for determining       > whether 𝓜 ever prints 0, and this is impossible, by §8. Hence the       > Entscheidungsproblem cannot be solved/ [Tur26 p262]       >       > yes he is ultimately also disproving the entscheidungsproblem, but he's       > motivated in doing so specifically because it aligns with godel's       > previous result, and his paper ultimately strengthens godel's result,       > even if the specific method *is* quite different       >       >> using what we now call the halting theorem to derive results about       >> computation numbers. In section 11 he says "It should perhaps be       >> remarked what I shall prove is quite different from the well-known       >> results of Gödel".       >>       >>> the halting problem variant was       >>> first described by kleene and/or davis       >>       >> The term was indeed coined later, but the result is right there in the       >       > not just coined later, but also described later. turing specifically       > tied his support of incompleteness to the "satisfactory number" paradox,       > not halting paradox       >       >> paper along with two proofs. He was inventing the whole subject on the       >> fly so it not surprising that we now use other terms, but a theorem by       >> another name shall smell as sweet.       >                     --       Copyright 2025 Olcott              My 28 year goal has been to make       "true on the basis of meaning" computable.              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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