A glass of water

It may have been Dietrich Bonhoeffer who drew the distinction (as a way of distinguishing 'rational' knowledge and the 'desiring intellect' of faith) between thinking about a glass of water on the one hand, and thinking about a glass of water because you are desperately thirsty on the other. Part of me wants to return that the desire in the latter bends knowledge wholly about the lines of its force, so that wanting there to be a God (say) overwhelms considerations of whether there actually is a God or not. But another part of me knows that's a cheap shot. A better way for an atheist to reply would be to find a way in which the second kind of thinking informs the former; the hope that rational apprehension of the universe would become as urgent and driven as faith.