Precisely. And that negative is what the entire atheist worldview is based on. "A-theist" means "not-god-ist." It is itself a negative.
And I don't agree with PJ's summary of the atheist world view. It's better summed up as "I see no reason to assume there might be a God, so I don't."
First, the fact that you see no reason to assume there might be a God has no bearing on whether there IS one; it speaks more about you than about Him. Secondly, I can see a myriad -- indeed, a universe -- of reasons to believe there IS a God, so I do.
In the end, both the belief and the un-belief are based on faith. So logic really doesn't go very far in arguing either side of the case.
No, un-belief isn’t based on faith. It’s just a lack of belief. Babies are atheists, until people fill their heads with tales. We are all born atheists.