Yhe simplest definition of "atheist" is one who lacks a belief in God. If you don't actively possess a belief that god exists, you're an atheist. Atheists confi

Yhe simplest definition of "atheist" is one who lacks a belief in God. If you don't actively possess a belief that god exists, you're an atheist. Atheists confidently disbelieve in god in exactly the same way that they disbelieve in Santa Claus - the mere fact that humans tell stories about some mythical creature doesn't mean that creature exists. But the bigger problem is the definition of God. Without defining it, the question "does it exist" is of course unanswerable. But if you mean "the Judeo-Christian God, the guy described in the bible" then one potentially can prove that it doesn't exist. Maybe you can't disprove the existence of ALL gods or rather all definitions of god, since the full set includes Spinoza's version. (If you choose to define god as being the same the universe and allow that the universe exists, then "god" exists.) But you CAN disprove the existence of THAT ONE particular god, because it is defined in self-contradictory ways. The "God" that religious people seem to be talking about most of the time is logically incoherent. So believing it doesn't exist is like believing something that's simultaneously green and invisible doesn't exist. God is what you get when you start with Santa Claus and turn all the absurdity knobs up to 11. Omnipotent and omniscient, yet somehow allows us all free will even though he knows everything we'll ever do. "existed before the universe", even though the universe is defined as "everything that exists". And so on.