To address that all familiar arguement...
By definition I am an atheist, yet as has been said by yourdeadgroom, it's not that I choose to 'BELIEVE there isn't a god' it's more 'I haven't been given enough proof that there is a good so I choose to dismiss the concept'... it doesn't really matter which way you word it though, it just becomes rhetorical but the main point stands that as far as atheists go 'since there is not enough substantial proof for me, I choose not to believe that there is a god' (which you could obviously word as 'I choose to BELIEVE there isn't a god' which is essentially the same thing).
See this is the thing I hate about the English language (and probably others... don't know many, excuse me for that). If you word things a certain way you can let someone fall into your worded traps, which is basically just rhetorical bullshit.
When I was born... I had no idea of 'god', didn't fathom of the concept of 'god' so therefore I obviously did not BELIEVE in 'god'... so as far as it goes, aren't we all born Atheist? So as I go through life and I see these people and they give their faith to god... and I wonder why, exactly, I should accept their beliefs of one when there is obviously no reason to believe in one, appart from one's personal insecurities... there is as much proof of a 'god' existing as there is explanation of what happens where science currently has a gray area. Basically this concept of 'god' fills the void of things that we don't know.. which is why I REFUSE to believe in something so seemingly blinding, self-defeating and entrapping and when looked at thoroughly, ludicrous.
Also the Adam and Eve story that has been brought about... if you don't yet understand that this story is just an analogy (metaphor, allegory, whatever the hell you wanna call it) that sets a basis moral ground for what the bible TELLS you is right and wrong, then I can't help but pity you.
The stories within the bible are just to be drawn as parallels to what can happen in real-life if we do not obey the tennants of the bible... it's a book filled with stories reinforcing the 'Christian' moral ground as well as reinforcing that all too popular concept of god, which with the bible is so riddled with contradictions and metaphors, it's hard to know what to take literally... then again the bible was written in an age where people were alot dumber, ignorant and more gullible so I'm assuming not many questioned these things.
All this questioning... THIS is what makes me atheist... this to me is the real definition of someone who refuses to believe in god.