Atheists don't believe they know everything, they just believe that people are full of shit when they talk about Gods or similar. It doesn't require any belief

Atheists don't believe they know everything, they just believe that people are full of shit when they talk about Gods or similar. It doesn't require any belief in the existence of or lack of supernatural things, just figuring out that it is much more likely that people are manipulative liars than that they got some profound message from some higher being.