Sujet : Re: Every D correctly simulated by H never reaches its final state and halts
De : richard (at) *nospam* damon-family.org (Richard Damon)
Groupes : comp.theoryDate : 19. May 2024, 19:17:40
Autres entêtes
Organisation : i2pn2 (i2pn.org)
Message-ID : <v2dc7k$1g2n9$7@i2pn2.org>
References : 1 2 3 4 5 6 7 8 9 10
User-Agent : Mozilla Thunderbird
On 5/19/24 9:59 AM, olcott wrote:
On 5/19/2024 8:43 AM, Mikko wrote:
On 2024-05-19 12:36:08 +0000, olcott said:
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On 5/19/2024 5:37 AM, Mikko wrote:
On 2024-05-18 14:38:53 +0000, olcott said:
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On 5/18/2024 4:45 AM, Mikko wrote:
On 2024-05-17 15:55:03 +0000, olcott said:
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On 5/17/2024 4:08 AM, Mikko wrote:
On 2024-05-17 07:25:52 +0000, Fred. Zwarts said:
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Op 17.mei.2024 om 03:15 schreef olcott:
The following is self-evidently true on the basis of the
semantics of the C programming language.
>
typedef int (*ptr)(); // ptr is pointer to int function
00 int H(ptr x, ptr x);
01 int D(ptr x)
02 {
03 int Halt_Status = H(x, x);
04 if (Halt_Status)
05 HERE: goto HERE;
06 return Halt_Status;
07 }
08
09 int main()
10 {
11 H(D,D);
12 return 0;
13 }
>
In the above case a simulator is an x86 emulator that correctly
emulates at least one of the x86 instructions of D in the order
specified by the x86 instructions of D.
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This may include correctly emulating the x86 instructions of H
in the order specified by the x86 instructions of H thus calling
H(D,D) in recursive simulation.
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Any H/D pair matching the above template where
D(D) is simulated by the same H(D,D) that it calls
cannot possibly reach its own line 06 and halt.
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*This is a simple software engineering verified fact*
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>
Note that olcott defines 'verified fact' as 'proven fact', but he is unable to show the proof. So, it must be read as 'my belief'.
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A "proven fact" without a proof is not worse than a "verified fact"
without a verification.
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>
*I updated my wording*
It is self-evidently true to anyone having sufficient knowledge
of the semantics of the C programming language.
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No, it is not. I would know if it were.
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If you do not understand that a single valid counter-example
would refute my claim then you don't know enough about proofs.
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Your claim
>
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Most people to not know the difference between deductive proof
]and inductive evidence.
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Most people don't read comp.theory so here we needn't care.
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If anyone is trying to prove me wrong they
must first understand what an actual proof is.
Several people here seem to think that ad hominem personal
attacks and insults are the basis for a valid rebuttal.
Richard has stated that he thinks that an example of
{D never simulated by H} ∈ {every D simulated by H}
No, the H that didn't simulate its input shows that once you allow H to not be required to be correct, that we can then have a trivial function that is "just as correct" (since wrong answers were allowed).
On 5/1/2024 7:28 PM, Richard Damon wrote:
Message-ID: <v0ummt$2qov3$2@i2pn2.org>
http://al.howardknight.net/?STYPE=msgid&MSGI=%3Cv0ummt%242qov3%242%40i2pn2.org%3E
It is self-evidently true to anyone having sufficient knowledge
of the semantics of the C programming language.
>
is a little unclear about the meaning of "It" but I think it
is false for any reasonable interpretation. Can I call myself
a counter-example?
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>