Re: On recursion and infinite recursion (reprise #3)

From	Mr Flibble <flibble@reddwarf.jmc>
Newsgroups	comp.theory
Subject	Re: On recursion and infinite recursion (reprise #3)
Message-ID	<20220508130212.00007ab6@reddwarf.jmc> (permalink)
References	(9 earlier) <t562a4$9ao$1@dont-email.me> <20220507161901.00002e54@reddwarf.jmc> <t57v4c$7do$1@dont-email.me> <20220508094913.00002e7c@reddwarf.jmc> <Q3OdK.15730$Bm21.3438@fx07.iad>
Organization	Jupiter Mining Corp
Date	2022-05-08 13:02 +0100

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On Sun, 8 May 2022 07:45:52 -0400
Richard Damon <Richard@Damon-Family.org> wrote:

> On 5/8/22 4:49 AM, Mr Flibble wrote:
> > On Sun, 8 May 2022 11:31:08 +0300
> > Mikko <mikko.levanto@iki.fi> wrote:
> >   
> >> On 2022-05-07 15:19:01 +0000, Mr Flibble said:
> >>  
> >>> On Sat, 7 May 2022 18:13:08 +0300
> >>> Mikko <mikko.levanto@iki.fi> wrote:
> >>>      
> >>>> On 2022-05-07 14:20:17 +0000, Mr Flibble said:
> >>>>      
> >>>>> On Sat, 7 May 2022 17:16:31 +0300
> >>>>> Mikko <mikko.levanto@iki.fi> wrote:
> >>>>>      
> >>>>>> On 2022-05-07 14:06:12 +0000, Mr Flibble said:
> >>>>>>      
> >>>>>>> On Sat, 7 May 2022 16:59:55 +0300
> >>>>>>> Mikko <mikko.levanto@iki.fi> wrote:
> >>>>>>>      
> >>>>>>>> On 2022-05-07 12:42:50 +0000, Mr Flibble said:
> >>>>>>>>      
> >>>>>>>>> On Sat, 7 May 2022 12:52:58 +0300
> >>>>>>>>> Mikko <mikko.levanto@iki.fi> wrote:
> >>>>>>>>>      
> >>>>>>>>>> On 2022-05-06 14:02:53 +0000, Mr Flibble said:
> >>>>>>>>>>      
> >>>>>>>>>>> The decider could never be compiled and run in the first
> >>>>>>>>>>> place due to the category error in the definition of the
> >>>>>>>>>>> proof.  
> >>>>>>>>>>
> >>>>>>>>>> An error in the definition of the proof does not prevent
> >>>>>>>>>> compilation and execution of the program.  
> >>>>>>>>>
> >>>>>>>>> In this case the error in the definition of the proof  
> >>>>>>>>
> >>>>>>>> No part of the proof is identified as errorneous, so the rest
> >>>>>>>> is irrelevant. Anyway,
> >>>>>>>>      
> >>>>>>>>> does prevent compilation unless  
> >>>>>>>>
> >>>>>>>> There is no option here, so the "unless" is void.
> >>>>>>>>      
> >>>>>>>>> the decider is made part of the program that is being
> >>>>>>>>> decided 
> >>>>>>>>
> >>>>>>>> The decider is made a part of the program discussed in the
> >>>>>>>> proof.  
> >>>>>>>>> in which case we get a function call-like infinite recursion
> >>>>>>>>> instead  
> >>>>>>>>
> >>>>>>>> We get or we don't get, depending on how the halt decider
> >>>>>>>> candidate attempts to decide.
> >>>>>>>>      
> >>>>>>>>> (as described by Pete Olcott) and we are attempting (and
> >>>>>>>>> failing) to decide if a procedure halts rather than if a
> >>>>>>>>> program halts.  
> >>>>>>>>
> >>>>>>>> In any case, the decider candidate fails to give the correct
> >>>>>>>> answer, and therefore is not a halt decider. Note that this
> >>>>>>>> is correctly inferred in the proof. Therefore either the
> >>>>>>>> conclusion of the proof is correct or you are wrong.  
> >>>>>>>
> >>>>>>> No answer is ever given due to the infinite recursion.  
> >>>>>>
> >>>>>> True about some candidates, false about others. For example, a
> >>>>>> candidate that always says "no" is not infinitely recursive but
> >>>>>> is wrong in the particular case discussed in the proof. But
> >>>>>> anyway, you have confirmed the conclusion of the proof.  
> >>>>>
> >>>>> False. The proof is not cognisant of the presence of the
> >>>>> infinite recursion.  The decider can never return an answer of
> >>>>> halts/doesn't halt due to the infinite recursion.  
> >>>>
> >>>> The correct term is decider candidate. It is not a decider
> >>>> because the infinite recursion prevents it from halting in
> >>>> finite time.
> >>>>
> >>>> You cannot call the proof incorrect merely because it agrees with
> >>>> you.  
> >>>
> >>> Try actually reading what Strachey wrote: a contradiction arises
> >>> based on the result of evaluating T[P] however T[P] is never
> >>> evaluated due to the infinite recursion: a fact ignored by the
> >>> proof.  
> >>
> >> If you can prove that the program does give the correct result in
> >> that case you have proven Strachey wrong. Otherwise you haven't.  
> > 
> > Strachey is wrong because he neglected to account for the infinite
> > recursion; this should be obvious to anyone who has actually read
> > and understood what Strachey wrote: it seems that you haven't.
> > 
> > /Flibble
> >   
> 
> No, because if T gets stuck in an infinite recursion, it is wrong, 
> because it failed to answer in finite time.
> 
> If T does answer in finite time, then there never was an infinite
> recursion.
> 
> All you have shown is that there exists a WRONG method to build a T
> that gets stuck, Like a T that needs to run its input to completion
> to answer about it.

I have shown that [Strachey, 1965] contains an infinite recursion and
is thus invalid.

/Flibble

Thread

On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-05 17:50 +0100
  Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-05 13:58 -0500
    Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-05 20:56 +0100
      Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-05 17:15 -0500
        Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-06 02:43 +0100
          Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-05 20:59 -0500
            Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-06 04:08 +0100
  Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-05 20:51 +0100
    Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-05 20:52 +0100
      Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-05 21:15 +0100
        Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-05 21:16 +0100
      Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-05 16:35 -0500
    Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-05 16:37 -0500
      Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-06 02:38 +0100
        Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-05 20:42 -0500
          Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-06 03:59 +0100
  Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-05 22:33 -0400
    Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-06 15:02 +0100
      Re: On recursion and infinite recursion (reprise #3) Python <python@example.invalid> - 2022-05-06 16:18 +0200
        Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-06 11:55 -0500
      Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-07 12:52 +0300
        Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-07 13:42 +0100
          Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-07 16:59 +0300
            Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-07 15:06 +0100
              Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-07 17:16 +0300
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-07 15:20 +0100
                Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-07 18:13 +0300
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-07 16:19 +0100
                Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-07 11:03 -0500
                Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-07 23:41 +0100
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-07 23:43 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-07 19:59 -0400
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 01:01 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-07 20:18 -0400
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 01:55 +0100
                Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-08 11:31 +0300
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 09:49 +0100
                Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-08 13:00 +0300
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 12:57 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-08 07:45 -0400
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 13:02 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-08 08:31 -0400
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 13:39 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-08 14:10 -0400
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 20:06 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-08 15:39 -0400
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 21:14 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-08 17:40 -0400
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-08 23:04 +0100
                Re: On recursion and infinite recursion (reprise #3) Ben <ben.usenet@bsb.me.uk> - 2022-05-09 00:26 +0100
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-08 19:40 -0400
                Re: On recursion and infinite recursion (reprise #3) olcott <NoOne@NoWhere.com> - 2022-05-09 10:55 -0500
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-09 20:13 -0400
                Re: On recursion and infinite recursion (reprise #3) olcott <NoOne@NoWhere.com> - 2022-05-09 10:51 -0500
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-09 18:31 +0100
                Re: On recursion and infinite recursion (reprise #3) olcott <NoOne@NoWhere.com> - 2022-05-09 12:36 -0500
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-09 20:15 -0400
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-09 20:14 -0400
                Re: On recursion and infinite recursion (reprise #3) olcott <NoOne@NoWhere.com> - 2022-05-09 10:49 -0500
                Re: On recursion and infinite recursion (reprise #3) Mr Flibble <flibble@reddwarf.jmc> - 2022-05-09 18:31 +0100
                Re: On recursion and infinite recursion (reprise #3) olcott <NoOne@NoWhere.com> - 2022-05-09 12:37 -0500
                Re: On recursion and infinite recursion (reprise #3) olcott <NoOne@NoWhere.com> - 2022-05-09 10:47 -0500
                Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-09 19:33 +0300
                Re: On recursion and infinite recursion (reprise #3) olcott <NoOne@NoWhere.com> - 2022-05-09 11:36 -0500
                Re: On recursion and infinite recursion (reprise #3) Richard Damon <Richard@Damon-Family.org> - 2022-05-09 20:17 -0400
                Re: On recursion and infinite recursion (reprise #3) olcott <polcott2@gmail.com> - 2022-05-07 11:06 -0500
  Re: On recursion and infinite recursion (reprise #3) Mikko <mikko.levanto@iki.fi> - 2022-05-06 16:39 +0300

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