The case for atheism is reasoned that are many-thousand-fold.
Literally. And then there’s the lack of evidence. As a matter of fact, it’s not even a lack of evidence; no evidence exists to prove the existence of any god at all. So just to be clear: there have been many thousands of gods worshiped by many billions of people, and there hasn’t been one shred of evidence to prove any of them exist. Lastly, just read some religious texts. Religious scripture is the best case for atheism.
There have been over 3,000 deities in the history of worship (and this is a very conservative number). Almost every one of these deities are now classified as myth; Greek mythology, American Indian mythology, Celtic mythology, Norse mythology, etc. Today, there is one supposed god who is the supreme omniscient, omnipotent ruler and creator of the universe: the god of Abraham. This is the one god that the Jews, Christians, and Muslims all worship. Do Jews, Christians and Muslims believe in Norse gods, or American Indian gods? No. Therefore, they too are atheists when it comes to thousands of other gods.
As for the proof and evidence, the only thing you will find is apologetic theists trying to rationalize the existence of god. Rationalization is all good and well, but it doesn’t prove anything. Empirical evidence does. Just because one’s mind insists there must be a creator doesn’t mean a creator exists. Then there are theists who try to reverse the burden of evidence onto the atheist and say things like “You can’t prove it’s not true!” Well, no, atheists can’t prove it’s not true. But, then again, one can’t ask another to prove a negative. That would be like an agnostic or atheist asking a Christian to prove there isn’t an intergalactic star-eating dragon that breathes solar systems and defecates super-massive black holes. It doesn’t work.
Atheism should be the logical default position for all people.
If something can’t be proved, it shouldn’t be believed. Plain and simple. Having faith doesn’t make something any more real either. Having faith is simply the suspension of logical and reasonable thought. One could have faith that any given morning they will wake up 50 feet tall and be able to rip oak trees out of the ground and hurl them like so many lawn darts, but this isn’t possible and it’s not going to happen. If anyone really did think this was true, they would probably be admitted to an institution for the psychologically impaired.
All anyone has to do is read religious scripture cover-to-cover.
Take the Bible for instance: an ark fitting two of all living creatures? Where were the marsupials? Where were the dinosaurs and polar bears? Earth that’s 6,000 years old? A god who is jealous and tells people not to milk your cows on Sunday? A god who tells people not to carve engraved images? A god who tells his creation will burn and suffer eternal torment if they use his name in vain? Talking snakes, the magical fruit, a woman born of [a man’s] rib, and a burning bush that talks? A man living in a fish, a man walking on water, a man parting the seas, a man rising from the dead, and a man turning water into wine? Anyone with sensibility reads this and knows it’s simply untrue. And, really, what sort of universe-creating god could possibly be so stupid?