I have been an atheist since I was 15. I am now 26, and have read the full range of standard atheist arguments. The first one, which because it was first, probably had the most significant impact on me was George H. Smith's "Atheism: The Case Against God" which I purchased on Amazon along with Judith Hayes's "The Happy Heretic." I remember reading both books while thinking every page or two, "I considered this very point as I was losing my faith!" Later I read books by Dan Barker, Richard Dawkins, Christopher Hitchens, Sam Harris and so forth.
Each book was pretty much the same damn thing, but I loved reading them because I loved to see people in "my side" making such lucid, clear, wonderful arguments. I used those arguments when defending my atheist viewpoint to my friends. I don't seek out argument by any means, but I certainly welcome a debate when it comes my way. I think most people that join sites like ThinkAtheist are probably like me in this respect. I love nothing more than the opportunity to talk about religion, and I'm anything but religious.
I have noticed, as I see my new atheist friend's blogs, facebook posts, and twitter conversations, that they all crave this debate. One recent blog post was merely a two sentence invite to IM her and debate atheism vs. theism.
What is it about us that makes us crave the debate so much? What makes us read these books that merely reinforce what we already know? I love nothing more than youtubing a Christopher Hitchens slapdown just because it gives me goosebumbs and makes me feel good that there are people out there articulating the atheist argument with such brash eloquence. Maybe I am weird, but I don't think I am wrong.
Maybe our inquisitive nature - which made us atheists in the first place - makes us more predisposed to reveling in debates, arguments, disagreements, and defenses of our view. But that's just a theory. ;-)
Well, I recognize that it requires collaboration/consensus to ensure that our understanding is the best that it can be. It's easy to miss something and come to incorrect conclusions so I like to be very conservative in my epistemic credulity.
I was discussing this issue just the other day and I told the guy it wasn't enough for him to find evidence that supported his view (he had an extremely over-simplistic set of tests for his belief). I told him he needed to get questions and challenges from the experts in the field as well, and I (even as a non-expert) rattled off half-a-dozen issues he had not addressed at all which completely disproved his hypothesis.
It's only when nobody can find any holes, the outliers in the data are accounted for, and those who accept the hypotheses agree that those who reject it are just being disagreeable and do not have any legitimate objection that we can really begin to start accepting the hypothesis as a Theory.
Another factor is knowing the holes and errors in bad hypotheses that are actually held by far too many people and hoping to make some small dent in the number of people holding those false beliefs.
I can't speak for other atheists but I like debate because I'm tired of only hearing one side of the story, and that story is a pretty lame one, at that.
For me it's the argument that religious law should be instated because whatever religion is true and correct.
I guess what I mean here is, without debate and argument, the USA (and Australia, it's like little-America here sometimes) really would be a Christian country. Abortion would be illegal. Gay marriage and equality would be totally off the table. Basically whatever the wacky christians wanted in the law they would get because they would claim it is a divine law from their god. Debating against their religion is (imo) the only way we have to say "we don't believe in your god therefore the divinity of this law is null". Same goes for other religions too of course, christianity is just the most prevalent in our societies.
Hope that made sense, I havn't been sleeping well lol.