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by alexmolas 1327 days ago
The Halting Problem forbids you to build an algorithm that proves if a generic problem halts or not. This doesn't forbid you to check if a specific algorithm halts or not. For example, you know that the specific program `print("Hello World")` halts. So you can remove the ones that do not halt by inspecting them one by one and developing a specific algorithm for each one that determines if it halts or not.
1 comments

If you could inspect any Turing machine and devise a specific algorithm that determines if it halts, then you yourself would be an algorithm that solves the generic halting problem.
no, because you can build an algorithm that fools the algorithm that solves the generic halting problem. I wrote a "proof" of that in my blog [1]

[1]: https://www.amolas.dev/blog/halting-problem/

Exactly. So your claim that:

> So you can remove the ones that do not halt by inspecting them one by one and developing a specific algorithm for each one that determines if it halts or not.

Is impossible. You can’t, in general, inspect Turing machines one-by-one to determine if they halt.