Atheists... why do you believe that God doesn't exist?

[Coffee Jesus]

Believer: Because the fine-tuning of the universe for life is exponentially more likely on theism than on naturalism, and thus constitutes a strong probabilistic argument for theism. [This does in fact seem to be true]

Maybe a topic for another thread, but there is a smidgen of evidence for one of the multiverse theories that explains this fine-tuning.

I'm not saying you're wrong, but there is a simpler and better supported explanation.

Ahh, here it is. http://www.scientificamerican.com/articl...-universe/

Oh, you might've got the wrong impression. I'm not saying there aren't potential naturalistic explanations for cosmic fine-tuning (otherwise I wouldn't be a naturalist :p), but that such is more likely to occur if theism is true.

If there are naturalistic explanations, then this degree of fine-tuning wasn't in fact that improbable on atheism, thus it shouldn't be "exponentially more likely on theism".
Are you taking into account that a god might have made the world even better than it actually is?

However, an even stronger fine-tuning argument can be made that goes beyond just fine-tuning of the universe, and it's probably the best argument for theism I've seen.

This has turned into a general thread for debating (a)theism, so you might as well describe it.