Re: The proof that I was referring to is on the website

From: Peter Olcott (olcott_at_worldnet.att.net)
Date: 08/11/04

  • Next message: Kent Paul Dolan: "Re: What is the Result from Invoking this Halt Function?" 
    Date: Wed, 11 Aug 2004 02:23:11 GMT

    "The Ghost In The Machine" <ewill@aurigae.athghost7038suus.net> wrote in message news:86pmu1-32g.ln1@lexi2.athghost7038suus.net...
    > In sci.logic, Peter Olcott
    > <olcott@worldnet.att.net>

    > The machine which uses a side effect can be mapped 1-1 to a
    > machine which returns a result.

    If this assumption was not false, your reasoning would be sound.
    Finally something that is precise enough that I can precisely refute.

    Line 01) void LoopIfHalts(string SourceCode, string InputData)
    Line 02) {
    Line 03) if (WillHalt(SourceCode, InputData) == TRUE)
    Line 04) while (TRUE) // loop forever
    Line 05) ;
    Line 06) else
    Line 07) return; // FALSE or UNKNOWN
    Line 08) }

    As long as LoopIfHalts has exactly the same behavior when WillHalt
    returns TRUE as its behavior with values other than TRUE then you
    are correct, otherwise the 1-1 mapping has been disproven.

    Does LoopIfHalts have exactly the same behavior when WillHalt
    returns TRUE, as its behavior for any other return value?
    (This same answer is whether you are right or not).

    > If the first machine is
    > possible, so is the second.
    >
    > The second machine isn't possible. Therefore, neither is
    > the first.
    >
    > (That's a variant of modus tollens, and perfectly valid logic.)
    >
    > [.sigsnip]
    >
    > --
    > #191, ewill3@earthlink.net
    > It's still legal to go .sigless.

  • Next message: Kent Paul Dolan: "Re: What is the Result from Invoking this Halt Function?"

    Relevant Pages
    • Quantcast