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by furyofantares 26 days ago
"in general" in mathematics means "in all cases, without exception", rather different than the normal usage where it means "usually, but not always".

If a mathematician using the mathematical sense of the word general says "it is not in general possible to tell if a program will halt by inspecting it", they're talking about the halting problem, even if you've looked at lots of programs where you can tell if they'll halt or not, and your experience might be correctly described using the normal usage of the word with "in general I can tell if a program will halt or not".

1 comments

I'm a mathematician AND I understand English. Your statement about the halting problem is not analogous to the one in question and your comment completely ignores my analysis, where I did in fact take "in general" to be universal, not some casual handwavy "usually". Again, as I said, what they apparently meant was (not (for all bugs B, it is possible to find B)), which is analogous to the halting problem statement, but is a completely irrelevant strawman since no one thinks or claims that code review can find all bugs, nor need it. (Likewise it is not possible for any TM to determine whether all programs halt, although there are infinitely many TMs that can determine whether some programs halt ... but this is disanalogous because the halting problem is concerned with "all" whereas code review is concerned with "some".)

I won't respond further.