Atheism is the belief that there is no God or superhuman, and thus the rejection of religion.
You basically just said the same thing.
Atheism is the lack of a belief, not a belief of a lack. The difference is that the former is simply choosing not to believe something, while the latter is an assertion. Most atheists will not claim that they know that god doesn't exist.
I guess I will take the time to responds to this though
to all atheists in this thread: prove to me he isn't
Whether this can be done or not depends on your definition of god. If you mean simply a god, in its most generic form possible, it can't be done. But if you mean a specific god, whose actions and the ways through which it works are very specifically defined (in a holy book, etc), then you can brown townyze these specific actions, and can be proven to either not occur at all, or occur for a completely natural reason. There's no reason to believe in say, the Christian God, when everything he supposedly does can be proven to not happen. The only explanation is that he wants to deliberately deceive us into not believing so he can punish us for falling for his trick, which is entirely irrational and does not fit the concept of a "good, loving god"
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