I justed wanted to say, how much I like this site. In my opinion, all those people who get upset and write angry letters just proof by doing so, that they are ignorant and don't believe in free speech.

However, I have my very own argument, why God can't exist:
The bible describes how God created the world.
Since a) this story is is physically impossible and b) no person was around to withness it, it must be fictional and thus not real.
Therfore: God is not real.
At least not the God thesists believe in.
It is after all a matter of definiton.
Maybe there IS some kind of intelligence, which created the universe,
but it is not the "perfect" guy who drowned humanity.

Thanks for the kind words about my site!

Responding to your argument against the existence of God:

1) I'd say that it's irrelevant that the creation story is physically impossible. If there were an omnipotent deity, nothing would be physically impossible. Only things that are logically impossible would be disallowed.

2) I assume you mean that Genesis must be fiction because it speaks of things that nobody witnessed. Religious people say that Genesis was divinely inspired, so God told the author (some say Moses) the relevant facts.

3) The Bible being fiction doesn't prove that there is no God -- but you hit the nail on the head when you say that the Bible not being true proves that the God theists (at least Biblically literal theists) believe in does not exists.

You are also right that it is a matter of definition. Many theists will say that they define God as "the creator of the universe," but they obviously have a definition in mind that is a lot more specific than that -- if you say that maybe some super alien scientist created our universe, they wouldn't agree that this alien was their God.

In fact, when you try and get theists to define God in a rigorous way, you often find that they cannot do so.