That physical damage to the brain results in loss or impairment of consciousness, and that there is absolutely no evidence that total biological death would entail anything but the cessation of this consciousness.
[EDIT: I want to be clear - I am NOT saying that it could never be the case that some form of "being" exists outside of what appears to us as a finite biological existence, I am merely pointing out that we have no evidence of this kind of existence, aside from vague spiritual feelings and experiences which are difficult to evaluate, so the skeptical position is the most honest one for the time being.]
>no evidence that total biological death would entail anything but
You seem very certain of your hypothesis. Is there anything that science has had a harder time defining, quantifying, or understanding than the nature of consciousness as it relates to reality? With that in mind it would seem more in keeping with the spirit of science to remain agnostic ("I don't know"), rather than atheistic ("I know")
>Those who raise questions about the God hypothesis and the soul hypothesis are by no means all atheists. An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence. Because God can be relegated to remote times and places and to ultimate causes, we would have to know a great deal more about the universe than we do to be sure that no such God exists. To be certain of the existence of God and to be certain of the nonexistence of God seem to me to be the confident extremes in a subject so riddled with doubt and uncertainty as to inspire very little confidence indeed.
[EDIT: I want to be clear - I am NOT saying that it could never be the case that some form of "being" exists outside of what appears to us as a finite biological existence, I am merely pointing out that we have no evidence of this kind of existence, aside from vague spiritual feelings and experiences which are difficult to evaluate, so the skeptical position is the most honest one for the time being.]