I don't believe (without proof on either side) anyone is an atheist, one can say they are but where is the evidence there is no divine something or other?. My girlfriend says she is an "atheist", there is always, always even if the spark is not viewable to others that the thought of a creator(s) or thought of "what if" after death. Everybody has it.
Can an atheist prove there is nothing? When even the top scientists cannot make a 100% connection of evolution to humans, and Clergy cannot prove that there is a God? One thing I do know through study is that the bible most certainly is not the word of God.
I am very agnostic, bordering on the "atheist" side, that there is no afterlife etc, which is why I very much read the Stoics, because like the rest of the world, no one can prove concrete evidence to either side whether there is or isn't.
I did watch recently a program, with these questions:
Where do streams come from. Answer: precipitation from the clouds. Ok. Where did the clouds come from, again precipitation, which is caused by the sun. Good. Where did the sun come from? From helium atoms exploding from hydrogen atoms. Where did hydrogen come from? From the big bang, hydrogen being the main element of life. What was before the big bang? NOTHING. And how could a living creator create if there were no elements for it to live.
I believe I have that in the right order. But there are still variants in the nothing...