Re: Incorrect questions and halt deciders

On 3/13/2024 7:34 PM, immibis wrote:

On 14/03/24 00:20, olcott wrote:

For any program H that might determine whether programs
halt, a "pathological" program D, called with some input,
can pass its own source and its input to H and then
specifically do the opposite of what H predicts D will do.
No H can exist that handles this case.
https://en.wikipedia.org/wiki/Halting_problem

>
It's a different D for every H. A lot of Hs correctly handle Ds for other Hs.
>

When you ask a man that has never been married:
Have you stopped beating your wife?

>
the correct answer is no.

 That affirms a false presupposition thus cannot be correct.

 

Although there is a mapping from some men to YES/NO
there is no mapping from never married men to YES/NO
thus the question is incorrect for all unmarried men.

>
the correct answer is no.
>

Although there is a mapping from some TM/input pairs to YES/NO
there is no mapping from H/D to YES/NO

H(D) isn't valid input since H has two inputs.

 there is no mapping from H(D,D) to YES/NO