Yes, you can in fact assume that you will never die, in a very narrow sense. I'm not saying it's necessarily a good assumption, but by the time you could have a

Yes, you can in fact assume that you will never die, in a very narrow sense. I'm not saying it's necessarily a good assumption, but by the time you could have an empirical experience proving you wrong, well you wouldn't have that experience because you would be dead. This illustrates that this question - only in this very narrow sense - is not an empirical question. It was in fact one of Kant's three "necessary postulates". He asserted that the question of subjective death was not empirical, and thus impossible to know or even gain confidence about one way or another, but he thought it was (for other reasons, related to his moral theory) necessary to assume that you would not subjectively die. Whether it's possible for this body you currently seem to be experiencing the world through to be ripped apart by a wild animal, though, that IS a highly empirical question.