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  • Re: Olcott correctly points out misconceptions in the HP proofs --- Bac

    From Richard Heathfield@21:1/5 to olcott on Wed Aug 20 18:34:41 2025
    On 20/08/2025 18:29, olcott wrote:

    <snip>

    Here is it 89 years later and even when
    specifically told that:

    Turing machine deciders only compute the mapping
    from their inputs...

    And it is self-evident that the caller of HHH(DD)
    cannot possibly be its input

    On the contrary, it is self-evident that you can pass in the
    executable file (DD.EXE, presumably), and have the whole thing
    available to you via fopen and fread and so on.

    If you can't see the whole of DD, you don't have a DD simulator.

    --
    Richard Heathfield
    Email: rjh at cpax dot org dot uk
    "Usenet is a strange place" - dmr 29 July 1999
    Sig line 4 vacant - apply within

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    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Heathfield@21:1/5 to olcott on Wed Aug 20 18:56:32 2025
    On 20/08/2025 18:42, olcott wrote:
    On 8/20/2025 12:34 PM, Richard Heathfield wrote:
    On 20/08/2025 18:29, olcott wrote:

    <snip>

    Here is it 89 years later and even when
    specifically told that:

    Turing machine deciders only compute the mapping
    from their inputs...

    And it is self-evident that the caller of HHH(DD)
    cannot possibly be its input

    On the contrary, it is self-evident that you can pass in the
    executable file (DD.EXE, presumably), and have the whole thing
    available to you via fopen and fread and so on.

    If you can't see the whole of DD, you don't have a DD simulator.


    typedef int (*ptr)();
    int HHH(ptr P);

    int DD()
    {
      int Halt_Status = HHH(DD);
      if (Halt_Status)
        HERE: goto HERE;
      return Halt_Status;
    }

    int main()
    {
      DD();
    }

    The same thing can be accomplished by making HHH()
    an operating system function that gets automatically
    invoked on main() before main is invoked. Same result
    DD() is rejected as non-halting and main() is never
    invoked.

    You're right! There are *lots* of ways to ignore DD's structure,
    and yes, there are *lots* of ways to get the wrong answer. So what?

    --
    Richard Heathfield
    Email: rjh at cpax dot org dot uk
    "Usenet is a strange place" - dmr 29 July 1999
    Sig line 4 vacant - apply within

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)