ADDED: I believe Dawkins's basic arguments in The God Delusion can be whittled down to three.
- God doesn't exist because I don't like him. Especially the God of the Old Testament. Yuck.
- Question authority, especially religious "authority." Do this because I'm telling you to.
- Evolution is the answer to everything. I know it's the answer to everything because if it wasn't, we wouldn't have an answer. Or we wouldn't eventually find out the answer. Because it will eventually answer everything, it is the answer to everything. It is this way because I'm telling you it is this way.