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	<20220508200637.0000491c@reddwarf.jmc> (permalink)
References	(13 earlier) <Q3OdK.15730$Bm21.3438@fx07.iad> <20220508130212.00007ab6@reddwarf.jmc> <iKOdK.8684$t72a.8070@fx10.iad> <20220508133909.00007b6b@reddwarf.jmc> <9ITdK.2055$wYy9.1130@fx11.iad>
Organization	Jupiter Mining Corp
Date	2022-05-08 20:06 +0100

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On Sun, 8 May 2022 14:10:13 -0400
Richard Damon <Richard@Damon-Family.org> wrote:

> On 5/8/22 8:39 AM, Mr Flibble wrote:
> > On Sun, 8 May 2022 08:31:10 -0400
> > Richard Damon <Richard@Damon-Family.org> wrote:
> >   
> >> On 5/8/22 8:02 AM, Mr Flibble wrote:  
> >>> 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
> >>>      
> >>
> >> No, you haven't. All you have shown is that one way to attempt to
> >> make the program that Strachev says doesn't exist, fails due to
> >> getting caught in infinite recursion.
> >>
> >> That just helps confirm Strachev, not refute it.  
> > 
> > Nope. Strachey's proof is based on a contradiction relating to
> > evaluating the result of T[P] however T[P] can never be evaluated if
> > there is an infinite recursion.
> > 
> > /Flibble
> >   
> 
> Nope, because if T actually meets the requirement to be able to take
> ANY program and answer, then it need to be able to take a program
> that uses a copy of T in it, as that is a valid program.
> 
> If T gets into an infinite recursion on such a program, it is that
> *T* fails to meet the requirements, not that the such a program is
> invalid to give to T.
> 
> This means that the program T is Strachey's proof can't just execute
> its input to get the needed answer, as that makes it (T) not meet its 
> requirements.
> 
> Thus, the "recursion" error isn't in the proof of impossibility, but
> in the candidate T that is attempting to be the counter example for
> the proof.
> 
> Recursion is allowed in programming and in math. If you try to just
> ban it, you will find you logic can't handle what it needs to.

You are simply wrong, and fractally so.  Try reading what Strachey
actually wrote.

/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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