Olbers' Paradox
Isn't this just an issue of comparing a countable and uncountable infinity? The number of points on the unit sphere is uncountable, but the number of stars is countable. As such there are in some sense more points on the sphere than there are stars, even though there are an infinite number of each.Take this together with the fact that intensity falls off as the square of the distance and it seems like the sky should be dark.