Re: What is the Result from Invoking this Halt Function?

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

Date: Wed, 04 Aug 2004 01:15:53 GMT

"Daryl McCullough" <daryl@atc-nycorp.com> wrote in message news:ceo8qv01dic@drn.newsguy.com...
> Simon G Best says...
>
> >>>>>>>So WillHalt02 checks if LoopIfHalts halts when given as input the source
> >>>>>>>to LoopIfHalts? But LoopIfHalts takes two parameters so how are you
> >>>>>>>breaking up LoopIfHalts into ProgramSourceFile and InputData?
> >>
> >> This question from five posts ago? (when there are that many levels
> >> of quote marks it doesn't look like a current question)
> >
> >It's only five posts ago because you failed to answer it when it was one
> >post ago, and failed to even read it when it was only three posts ago.
>
> Yes, this error, which Peter has made *repeatedly* without bothering
> to fix (even though the fix is trivial) is an important clue, I think,
> to Peter's problem. He's a programmer, so I'm sure he would never
> write
>
> void LoopIfHalts(String M, String x) {
> if (H(M,x)) {
> while (true) {}
> }
> }
>
> LoopIfHalts(LoopIfHalts);
>
> He would *know* that makes no sense, because (1) LoopIfHalts
> is defined to have two string arguments, and (2) LoopIfHalts
> is not a string, it is a program, so it makes no sense to treat
> it as if it were a string. (You need a coding function.)

So I make several trivial errors that have no effect on my main
point, from my single minded focus on this main point. So what?

> But Peter starts off by assuming the existence of a WillHalt
> function, and so he's already in fantasyland, so he thinks
> all bets are off. He throws out everything he knows about
> programming, including the fact that a function with two
> arguments can't be treated like a function with one argument.
> He throws out what he knows about programs, that---unless a
> program refers to global variables (or "static variables" in
> Java), or gets inputs from the user, or reads from some input
> stream, or uses a random number generator---if you run the same
> program twice on the same arguments, you will typically get the
> same result.
>
> Some people have a real problem with conditional reasoning. Once
> they start reasoning under a counterfactual assumption, they toss
> out everything they know.
>
> --
> Daryl McCullough
> Ithaca, NY
>

Relevant Pages

  • Re: floyd problem
    ... " Check your trem edges and posts. ... next to the string tree is the locking ... "posts" that you'll see embeded into your guitar near the bridge. ...
    (alt.guitar.beginner)
  • Re: Data data from a Data Table
    ... I hadn't come back to check for posts on this after your pseudocode was ... I may end up using that pseudocode to present a report or something as I get ... Public Function fBuildSQL(strIN As String) As String ... Dim iCount As Long ...
    (microsoft.public.access.modulesdaovba)
  • Re: Implicit expressions of speed of gravity within Newtonian mechanics
    ... responding to posts like yours. ... How many predictions do string ... one of the things that distinguishes your conjecture from ...
    (sci.physics.relativity)
  • Re: Computer Name - Best way to obtain this VB.Net
    ... Thanks for all of the feedback on this and my recent posts. ... You could also use the MAC address as this is specific to the NIC card ... Public Function GetDriveSerialNumber(ByVal sDriveLetter As String) As ... Dim HardDiskProperty As PropertyData = ...
    (microsoft.public.dotnet.languages.vb)
  • Re: What is the Result from Invoking this Halt Function?
    ... and failed to even read it when it was only three posts ago. ... > is defined to have two string arguments, ... > Some people have a real problem with conditional reasoning. ...
    (sci.logic)