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Re: On Strachey

From Ben <ben.usenet@bsb.me.uk>
Newsgroups comp.theory
Subject Re: On Strachey
Date 2022-05-06 02:34 +0100
Organization A noiseless patient Spider
Message-ID <87czgrmok4.fsf@bsb.me.uk> (permalink)
References (1 earlier) <t51fm3$915$1@dont-email.me> <20220505223908.00001a9e@reddwarf.jmc> <t51gn6$fjt$2@dont-email.me> <20220505225335.00007d75@reddwarf.jmc> <t51ig5$t3s$4@dont-email.me>

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olcott <polcott2@gmail.com> writes:

> On 5/5/2022 4:53 PM, Mr Flibble wrote:
>> On Thu, 5 May 2022 16:48:21 -0500
>> olcott <polcott2@gmail.com> wrote:
>> 
>>> On 5/5/2022 4:39 PM, Mr Flibble wrote:
>>>> On Thu, 5 May 2022 16:30:41 -0500
>>>> olcott <polcott2@gmail.com> wrote:
>>>>    
>>>>> On 5/5/2022 2:45 PM, Mr Flibble wrote:
>>>>>> Strachey's "Impossible Program" [Strachey, 1965] is indeed
>>>>>> impossible but not for the reason Strachey suggests. Strachey's
>>>>>> impossible program is impossible not due to the contradiction he
>>>>>> posits but is instead impossible due to an invalid infinite
>>>>>> recursion (a category error in this case) which prevents the
>>>>>> contradiction from ever being realised. As Strachey claims his
>>>>>> "Impossible Program" proof is based on communication he had with
>>>>>> Turing it seems reasonable to assume that Turing's proof has the
>>>>>> same flaw.
>>>>>>
>>>>>> I suppose at some point I should stop trolling and actually read
>>>>>> what Turing wrote so I don't have to rely on what seems
>>>>>> reasonable. :D
>>>>>>
>>>>>> /Flibble
>>>>>>       
>>>>>
>>>>> What Turing wrote never mentions halting:
>>>>> https://www.cs.virginia.edu/~robins/Turing_Paper_1936.pdf
>>>>
>>>> "Alan Turing proved in 1936 that a general algorithm to solve the
>>>> halting problem for all possible program-input pairs cannot exist"
>>>> [Wikipedia, 2022]
>>>>
>>>
>>> Yes what you said is equally true:
>>> https://www.sciencedirect.com/science/article/pii/S235222082100050X
>>
>>   The fact it wasn't called The Halting Problem when Turing wrote his
>> paper doesn't really change any facts on the ground?
>
> Right, so it proves that you are right and Ben is wrong.
> What Turing wrote in 1936 is now known as the halting theorem.

Two people who have not read the paper have persuaded themselves that
someone who has must be wrong about it.  Is there any need for facts?

Turing's 1936 paper is not about halting.  It proves a related theorem
about the outputs -- the symbols a TM writes to the tape.  Did Turing
know, in 1936, that halting could not be decided?  Almost certainly.
But he didn't prove it because his concern was about the strings
written, even those that are not finite.

(It also uses a term, "cycle-free" that is likely to mislead the casual
reader.)

-- 
Ben.
"le génie humain a des limites, quand la bêtise humaine n’en a pas"
Alexandre Dumas (fils)

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Thread

On Strachey Mr Flibble <flibble@reddwarf.jmc> - 2022-05-05 20:45 +0100
  Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-05 16:30 -0500
    Re: On Strachey Mr Flibble <flibble@reddwarf.jmc> - 2022-05-05 22:39 +0100
      Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-05 16:48 -0500
        Re: On Strachey Mr Flibble <flibble@reddwarf.jmc> - 2022-05-05 22:53 +0100
          Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-05 17:18 -0500
            Re: On Strachey Ben <ben.usenet@bsb.me.uk> - 2022-05-06 02:34 +0100
              Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-05 20:40 -0500
                Re: On Strachey Ben <ben.usenet@bsb.me.uk> - 2022-05-06 03:53 +0100
              Re: On Strachey Mr Flibble <flibble@reddwarf.jmc> - 2022-05-06 02:59 +0100
                Re: On Strachey Ben <ben.usenet@bsb.me.uk> - 2022-05-06 03:50 +0100
                Re: On Strachey Jeff Barnett <jbb@notatt.com> - 2022-05-05 23:01 -0600
                Re: On Strachey Mr Flibble <flibble@reddwarf.jmc> - 2022-05-06 15:42 +0100
                Re: On Strachey Mr Flibble <flibble@reddwarf.jmc> - 2022-05-06 14:56 +0100
                Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-06 11:58 -0500
                Re: On Strachey Ben <ben.usenet@bsb.me.uk> - 2022-05-07 01:11 +0100
                Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-06 19:31 -0500
                Re: On Strachey Ben <ben.usenet@bsb.me.uk> - 2022-05-07 02:07 +0100
                Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-06 20:34 -0500
                Re: On Strachey Richard Damon <Richard@Damon-Family.org> - 2022-05-06 23:08 -0400
                Re: On Strachey Ben <ben.usenet@bsb.me.uk> - 2022-05-07 23:47 +0100
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-07 18:14 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-07 16:35 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-07 19:19 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-07 17:48 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-07 20:08 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-07 18:26 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-07 21:20 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-07 19:36 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 10:31 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 09:02 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 11:05 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 09:30 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 11:39 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 09:52 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 12:18 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 10:26 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 15:17 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 13:27 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 15:51 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 13:59 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 16:19 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 14:30 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 17:24 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 15:56 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 18:13 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 16:44 -0700
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 19:52 -0400
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 19:50 -0400
                Re: On Strachey [ How nuts is that? ] wij <wyniijj2@gmail.com> - 2022-05-09 14:51 -0700
                Re: On Strachey [ How nuts is that? ] wij <wyniijj2@gmail.com> - 2022-05-09 14:53 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 17:18 -0500
                Re: On Strachey [ How nuts is that? ] wij <wyniijj2@gmail.com> - 2022-05-09 15:34 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 17:44 -0500
                Re: On Strachey [ How nuts is that? ] wij <wyniijj2@gmail.com> - 2022-05-09 15:53 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 18:03 -0500
                Re: On Strachey [ How nuts is that? ] wij <wyniijj2@gmail.com> - 2022-05-09 16:11 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 18:19 -0500
                Re: On Strachey [ How nuts is that? ] wij <wyniijj2@gmail.com> - 2022-05-09 16:23 -0700
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 18:30 -0500
                Re: On Strachey [ How nuts is that? ] wij <wyniijj2@gmail.com> - 2022-05-09 16:42 -0700
                Re: On Strachey [ How nuts is that? ][ proof that I am correct ] olcott <NoOne@NoWhere.com> - 2022-05-10 07:16 -0500
                Re: On Strachey [ How nuts is that? ][ proof that I am correct ] Richard Damon <Richard@Damon-Family.org> - 2022-05-10 19:23 -0400
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 20:02 -0400
                Re: On Strachey [ How nuts is that? ] Jeff Barnett <jbb@notatt.com> - 2022-05-09 16:12 -0600
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 17:36 -0500
                Re: On Strachey [ How nuts is that? ] Jeff Barnett <jbb@notatt.com> - 2022-05-09 20:13 -0600
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 23:39 -0400
                Re: On Strachey [ How nuts is that? ] olcott <NoOne@NoWhere.com> - 2022-05-09 22:22 -0500
                Re: On Strachey [ How nuts is that? ] Dennis Bush <dbush.mobile@gmail.com> - 2022-05-09 20:48 -0700
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 19:43 -0400
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 19:40 -0400
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 19:39 -0400
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-09 19:37 -0400
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-07 21:09 -0400
                Re: On Strachey [ How nuts is that? ] Richard Damon <Richard@Damon-Family.org> - 2022-05-07 21:22 -0400
                Re: On Strachey [ How nuts is that? ] Ben <ben.usenet@bsb.me.uk> - 2022-05-08 00:46 +0100
                Re: On Strachey Ben <ben.usenet@bsb.me.uk> - 2022-05-07 00:58 +0100
  Re: On Strachey Mikko <mikko.levanto@iki.fi> - 2022-05-06 16:09 +0300
    Re: On Strachey Mr Flibble <flibble@reddwarf.jmc> - 2022-05-06 14:59 +0100
      Re: On Strachey Mikko <mikko.levanto@iki.fi> - 2022-05-06 19:16 +0300
        Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-06 11:49 -0500
      Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-06 12:10 -0500
    Re: On Strachey olcott <polcott2@gmail.com> - 2022-05-06 12:34 -0500

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