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Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ]

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olcott <NoOne@NoWhere.com> writes:

> On 7/31/2021 5:17 PM, Ben Bacarisse wrote:
>> olcott <NoOne@NoWhere.com> writes:
>> 
>>> On 7/30/2021 3:47 PM, Ben Bacarisse wrote:
>> 
>>>> It does not matter what the trace shows.  The trace can show some code
>>>> deciding absolutely anything, either correctly or incorrectly, and still
>>>> not refute Rice's theorem.  Rice's theorem is about the decidability of
>>>> sets.
>>>
>>> If there exists no undecidable counter-example showing the Rice's
>>> theorem is true then it would seem that Rice's theorem would have no
>>> basis.
>> There is no such thing as an undecidable example (singular).  But I
>> think you now agree with me: nothing you have posted says anything about
>> the soundness of the theorem.  The "if ... then it would seem..."
>> pattern suggest you know you haven't proved anything.
>
> // Simplified Linz Ĥ (Linz:1990:319)
> // Strachey(1965) CPL translated to C
> void P(u32 x)
> {
>   if (H(x, x))
>     HERE: goto HERE;
> }
>
> int main()
> {
>   Output("Input_Halts = ", H((u32)P, (u32)P));
> }
>
> I call the above an HP counter example instance.

I can't stop you.  Is the fact that a key part of the program is missing
what makes it an "HP counter example instance"?

What the rest of the world calls "HP instances" are actual programs
(plus any required input).  But as I've said, you are using words to
suggest things, poetically, in the reader's mind, not to communicate a
precise technical meaning.

>> I won't even try to understand what a "counter-example showing the
>> Rice's theorem is true" is.  If you read a book on this topic (properly,
>> not just scanning it), you'd pick the language and might end up knowing
>> how to say what you mean.
>
> Try an find a case where my PSR_Decider() can't possibly get the
> correct answer.

Post the code and I'll see what I can do.  You'll have to define
"correct answer" as well because you use those words quasi-poetically
too.  It's quite possible your code does always give the "correct
answer".  After all, your "halt decider" gives the "correct answer" for
the case you obsess about.

>> I've accused you before of writing "math poems" when you try to use
>> symbolic notation, but I've just realised you do it with words as well.
>> You don't really know what "decidable", "counter-example" and "Rice's
>> theorem" mean. 
>
> I have shown this concretely.

Eh?  You are confirming that you have shown, concretely, that you do
indeed use words poetically without really knowing what they mean?  I
don't think you wanted to say that.

>> You don't even know what mathematicians mean by "true",
>
> They have since Tarski added the whole convoluted mess of model theory
> on top of Tarski's original simple notion.
>
>> so when you string them all together like this, the reader has to
>> analyse the poem to see how you are using these words as metaphors.  If
>> the reader can do that, they will know what you mean.
>
> I asked you for the proper terminology for the HP counter-example
> instance that I provided above and you indicated that there is none.

Yes, the notion is daft.  You use the words to hint that there is
something fishy going on when there is not.  I can't help you find
correct words to say something daft.

There are infinitely many HP instances.  There are infinitely many TMs.
Infinitely many of those TMs are deciders.  None of those deciders is a
halt decider.  Every decider gets an infinite number of HP instances
wrong.  It's all much simpler than you think.

-- 
Ben.

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Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 08:46 -0500
  Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-30 15:09 +0100
    Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 10:40 -0500
      Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-30 19:27 +0100
        Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 13:45 -0500
          Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Richard Damon <Richard@Damon-Family.org> - 2021-07-30 13:28 -0700
          Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-30 21:47 +0100
            Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 16:43 -0500
              Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Richard Damon <news.x.richarddamon@xoxy.net> - 2021-07-30 14:51 -0700
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 16:59 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Richard Damon <Richard@Damon-Family.org> - 2021-07-30 15:21 -0700
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 17:45 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2021-07-30 16:32 -0700
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 18:44 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Richard Damon <Richard@Damon-Family.org> - 2021-07-30 17:25 -0700
              Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-07-31 23:17 +0100
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-31 21:34 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-08-01 11:22 +0100
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-08-01 23:07 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-08-02 17:32 +0100
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-08-02 13:37 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-08-03 01:25 +0100
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-08-02 20:02 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-08-03 02:58 +0100
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-08-02 21:26 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-08-03 04:10 +0100
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-08-02 22:39 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Richard Damon <Richard@Damon-Family.org> - 2021-08-02 22:29 -0700
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-08-04 19:45 +0100
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Richard Damon <Richard@Damon-Family.org> - 2021-08-02 22:22 -0700
  Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] André G. Isaak <agisaak@gm.invalid> - 2021-07-30 11:06 -0600
    Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 12:11 -0500
      Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] André G. Isaak <agisaak@gm.invalid> - 2021-07-30 15:46 -0600
        Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 16:53 -0500
          Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] André G. Isaak <agisaak@gm.invalid> - 2021-07-30 16:13 -0600
            Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 17:43 -0500
              Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] André G. Isaak <agisaak@gm.invalid> - 2021-07-30 17:01 -0600
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] André G. Isaak <agisaak@gm.invalid> - 2021-07-30 17:18 -0600
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 18:34 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] André G. Isaak <agisaak@gm.invalid> - 2021-07-30 20:05 -0600
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 21:33 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] André G. Isaak <agisaak@gm.invalid> - 2021-07-30 21:09 -0600
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] olcott <NoOne@NoWhere.com> - 2021-07-30 22:23 -0500
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Richard Damon <Richard@Damon-Family.org> - 2021-07-30 20:57 -0700
                Re: Pathological self-reference(Olcott 2004) decider [ Defeating Rice's Theorem ] Jeff Barnett <jbb@notatt.com> - 2021-07-30 22:26 -0600

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