Brandon Fibbs has a beautiful post at On Faith about how Carl Sagan took his faith away and replaced it with something so much better:

I did not abandon my faith because I was hurt or angry or disillusioned. I did not abandon my faith because I wanted to rebel, or live a life of sin, or refuse god’s authority. I left because I could no longer believe. I left because I felt there simply was no convincing evidence for my belief. I left because my faith insulted reason one too many times. I left because once I applied the same level of skepticism and incredulity to Christianity that I always had to all other faiths, it likewise imploded. Once I accepted that the Bible’s account of cosmic and human origins could not possibly be true, I began to realize that it was just the first in an interminably long line of things the Bible was wrong about.

Science killed my faith. Not “science,” the perverse parody invented by some Christians — a nefarious, liberal, secular agenda whose sole purpose is to turn people from god — but rather science, an objective, methodological tool that uses reason and evidence to systematical study the world around us, and which is willing, unlike faith, to change direction with the accumulation of that evidence. Science is a humble and humbling exercise. Science is the impossibly dense core of curiosity — always asking, always seeking, always yearning to know more, never satisfied.