>From: "David Abrahams" <[EMAIL PROTECTED]> > Terje Slettebų <[EMAIL PROTECTED]> writes: > > > No. You can't prove a negative, an impossibility. > > I think that's wrong, and here's my one white crow to prove it ;-) > > I can prove that there can never exist a positive integral multiple of 2 which > is both greater than 2 and prime. > > It's the same as saying that *every* positive integral multiple of 2 > which is greater than 2 is a non-prime (now it's not a negative > statement anymore, but it is logically equivalent). The positive > integral multiples of 2 which are not greater than 2 are: 2. Since > every other positive integral multiple of 2 is divisible by both 2 and > itself, it must be non-prime.
Ok, so you can do it in a field where you decide on all the rules, such as maths. I was more thinking in terms of if you don't have all the facts. For example, many thought it was impossible to fly, and perhaps constructed "proofs" for it, using their available knowledge. However, it turned out to be possible, anyway, in a way they may not have known about. However, since the topic was whether it was possible to prove that you could not detect inheritance without an access violation, I guess that might be provable, as well, since you may decide on the logic used in the implementation. So it seems you're right. > But anyway, isn't this straying a little bit far from being on-topic? It is. Regards, Terje _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
