Cephus
Relentlessly Rational
I'm not saying that because it's in "our DNA" (as you say above) that it means it's correct or true or even rational. The fact that it's in "our DNA" suggest that people would have "belief" innately. Just that. Nothing more. Basically, we have a genetic (so to speak) tendency to believe, and only through rational thought and reason can we reach accurate understanding (which I think atheism really should stand for, the rational thought to save us from the innate misconceptions, but that's just what I think).
But it isn't in our DNA to believe in gods per se, that's just a corruption of what is actually in our DNA. Just like it's in our DNA to seek out patterns, it's a survival tactic that allows us to see human faces and danger otherwise disguised, but one of the things that also allows us to do is see shapes in clouds and Jesus on toast. That isn't why we have that coded into our genetics, it's just an unintended byproduct, just like belief in gods.
Well, then that's the problem, isn't it? If they can't comprehensible or coherent defined what theism is, then how can a-theism be anymore comprehensible?
Because this isn't between believing a thing and disbelieving a thing, it's between making a claim and rejecting that claim as nonsensical.
Theists believe in X. Atheists don't believe in X. X can be anything.
Well, in that case, X must be religious, otherwise "theism" and "atheism" have nothing whatsoever to do with it.