fgarb writes:
My question to atheists is, assuming you're right and the universe is entirely governed by logic with no supernatural phenomena, why does it follow that when you die you will no longer exist?
As with others, I agree that this doesn't necessarily follow. The evidence we have points to "no longer existing" in this universe/reality. However, that's also exactly what we'ed expect to see if we somehow end up existing in some other universe/reality, or even in this one again, at some as-yet-unknown repetition cycle that goes beyond human history. My official answer is that I don't know, and when my time comes, I'll welcome the new adventure.
A counterexample would be that if the universe is sufficiently large or infinite (which is certainly possible according to what is known of current cosmology unless I am well off my mark), then assuming the laws of physics are roughly constant over large distances, it is inevitable that you also exist elsewhere.
Why does infinite imply repetition? The set of real numbers is infinite, yet there are no repetitions. Why (assuming an infinite universe) must our reality include repetition simply because it's infinite?
You seem to imply that this is the case "assuming the laws of physics are roughly constant over large distances". But, if this is your reasoning, wouldn't the laws of physics necessarily have to be exactly constant over large distances? And this would assume that we have knowledge of all the laws of physics of the entire universe. I think that given even one law we don't fully understand, or even a slight variance in any known laws over large distances we'ed then have no requirement of duplication over an infinite space.
In short, I agree that your counterexample is valid in an infinite universe, but only if we fully understand all physical laws of the universe, and that they do not vary by any (even a very tiny) amount.