I think You got atheism wrong... We don't defy any God more than any other. Atheists are saying that there are no evidence for a God at large, and that the different religions of the world probably got things wrong.
If you are an atheist, You also accept that science might one day prove the existence of a deity.
It's just that all the guys trying to prove the existence of a deity has failed so far. Failed quite hard, too.
Bookmarks