I am insignificant.

[Spooky]

He means to be distinguishing between strong and weak atheism:

https://en.wikipedia.org/wiki/Negative_a...ve_atheism

Ok. Thank you. That makes a little sense. Still not sure how it's relevant, but I understand now.

[Pyrrho]

So your not agnostic/weak atheist? You believe God doesn't exist as opposed to simply not believing he exists.

Most people always talk about how they don't believe in God but don't deny him either, yet we see often it comes out they believe God doesn't exist.

In that case, what is your proof that he doesn't exist?

I know your question was not directed at me, but the proof would depend on the god under discussion.  For example, for a god that is supposed to be omnipotent, omniscient, and perfectly benevolent, the problem of evil proves that it cannot exist.  If we were talking about a limited god who is supposed to live on top of Mount Olympus, then I would suggest a trip to that mountain or referencing what people have found there.

If you were to insist on a proof that nothing that anyone might call a god exists, then that would be an absurd requirement, as people have said things like "Brad Pitt is a god!" and I defy anyone to prove that Brad Pitt does not exist.  Of course, when someone claims to be a strong atheist, they typically do not mean to be affirming that Brad Pitt does not exist.