By "was a proof to their eyes", I mean "was a demonstration to their eyes", in the "mathematical" sense of the term. You can have "legal" proofs that 2+2=5, fo

By "was a proof to their eyes", I mean "was a demonstration to their eyes", in the "mathematical" sense of the term. You can have "legal" proofs that 2+2=5, for example by having a lot of witnesses testifying it's the case, but you still don't have any "mathematical" proof and you will never have any, because if the hypothesis is fundamentally incorrect, it is impossible to have a correct demonstration that the hypothesis is correct. (and I hope no one will react to that with Gödel, it will just show that they totally missed the point) In both MacCarthyism and a witch hunt, even if the processes were super complicated, people were too easily accepting conclusions that are incorrect because they were too happy with these conclusions. This is for me the point of the expression "witch hunt", while the message I've reacted to explain that a witch hunt makes sense only if it concerns something that does not really exist.