CoolP, you seem to have completely misinterpreted my point.  ;)

Well, not completely. I was being human-centric, but that's because, let's face it, building spacecraft to visit other planets is a very human idea. My point was that, if life exists elsewhere, it wouldn't be [b]life as we know it[b], which means that it probably wouldn't be building spaceships to come visit us in.

I didn't talk about life as we know it, because the odds of that developing on other planets are nearly nonexistent, and if life exists in a completely different form from humans, then the whole UFO and extraterrestrial visitor points are moot, because life like that wouldn't be exploring the cosmos.

And the reason I said "extremely slim" is because the odds are something like a billion to one or more, and I didn't want to look it up. But to give you an idea, The Physics Book (which is a great book, by the way), says that if the rapid expansion that occurred one second after the big bang had been one part in one thousand million million (not sure what number that's supposed to be) off, the Universe would either have collapsed in on itself, or would have expanded too rapidly for subatomic particles to form atoms.

(And sorry for my apposition-filled, extraordinarily long sentences. I think I'm going to break the comma key on my keyboard pretty soon  ;D)