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|    Message 262,848 of 262,912    |
|    Mikko to olcott    |
|    Re: When halt provers are allowed to rej    |
|    08 Feb 26 11:06:04    |
      XPost: comp.theory       From: mikko.levanto@iki.fi              On 07/02/2026 15:08, olcott wrote:       > On 2/7/2026 4:15 AM, Mikko wrote:       >> On 06/02/2026 17:32, olcott wrote:       >>> On 2/6/2026 3:15 AM, Mikko wrote:       >>>> On 05/02/2026 13:28, olcott wrote:       >>>>       >>>>> On 2/5/2026 4:45 AM, Mikko wrote:       >>>>>> On 04/02/2026 18:47, olcott wrote:       >>>>>>       >>>>>>> A halt prover attempts to prove halting       >>>>>>       >>>>>> To prove that a computation halts is simple. Just show the execution       >>>>>> trace from the start to the halting. The hard problem is to prove       >>>>>> that an execution does not halt.       >>>>>>       >>>>>>> and when it detects that the proof of its input does not form       >>>>>>>       >>>>>>> *a well-founded justification tree within Proof*       >>>>>>> *theoretic semantics*       >>>>>>>       >>>>>>> Then it is correct to reject this input as bad data.       >>>>>>       >>>>>> No, that does not follow. That only means that it is correct to       >>>>>> reject       >>>>>> the proof. The conclusion of the proof may still be correct.       >>>>> The way that proofs work in proof theoretic       >>>>> semantics is that they reject inputs not having       >>>>> well-founded justification trees as bad data.       >>>>       >>>> An example of a valid input is "42". That input has no justification,       >>>> well-founded or otherwise. But there is no proof that would reject       >>>> "42" as bad data.       >>>       >>> It is an element of the set of natural numbers.       >>       >> True, but non necessarily relevant to tthe proof. But the current       >> question is whether the proof rejects the input "42" as bad data.       >       > Is the integer 42 a machine description that halts?       > Reject.              The question is already answered above: "42" is an input not having       a well-founded justification tree, or at least none that I know.              --       Mikko              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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