Re: Professor Eric Hehner's brilliant work --- isomorphisms

On 4/23/25 8:10 AM, olcott wrote:

On 4/23/2025 6:30 AM, joes wrote:

Am Tue, 22 Apr 2025 13:18:42 -0500 schrieb olcott:

On 4/22/2025 6:06 AM, Richard Damon wrote:

On 4/21/25 11:16 PM, olcott wrote:

On 4/21/2025 7:46 PM, Richard Damon wrote:

On 4/21/25 7:43 PM, olcott wrote:

On 4/21/2025 5:43 PM, Richard Damon wrote:

On 4/21/25 4:27 PM, olcott wrote:

>

WST Workshop on Termination, Oxford, 2018 Objective and Subjective
Specifications Eric C.R. Hehner Department of Computer Science,
University of Toronto
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(6) Can Carol correctly answer “no” to this (yes/no) question?
https://www.cs.toronto.edu/~hehner/OSS.pdf
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Is the perfect example of isomorphism to the halting problem's
pathological input. The halting problem input D derives a self-
contradictory question for H the same way that Carol's question is
self-contradictory for Carol.

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No it isn't, as Carol is a voltional being while a decider is
deterministic.
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How long are you going to pretend that you don't know what
isomorphisms are?

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When are you going to stop[ abusing the term.
To be an ISO-MORPHISM, they need to be "of the same shape".
The to things aren't of the same shape, as they aren't even of the
same type.
Thus, your comparison is just an ACTUAL type error, verse you made-up
type of type error.
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Bijective mapping.
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So, what BIjection are you talking about?
Carol, as she sits there can give two answers, Yes, or No.

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and both of them are the wrong answer.

Only when Carol gives it. The correct answer is the opposite.
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 Even a moron knows that self-contradictory questions
have no correct answer.

But the REAL question, does the program described by the input HAS a correct answer, at least if the Decider and the Input are actually programs.

 

When DD is able to actually do the opposite of whatever value that HHH
reports (it can't possibly do this) then HHH is being asked a question
where both yes and no are the wrong answer.

 

DD can most definitely do the opposite. Why shouldn't it?

 Because doing the opposite is unreachable code.

No it isn't, since your HHH returns 0.
It is only "unreachable" to the knowledge of HHH, since it stops simulating.

 

Like Carol, HHH is incapable of answering correctly.
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