It's interesting, that most theists believe that an Atheist "knows with certainty that a God/gods do not exist". So they admit to believe in something other people already know does not exist? The statement is not that Atheists claim to know, but that they actually know for sure (which is not possible for a human being anyway).
I think there is a big difference between the statement "There is no god" and the statement "I know with certainty that there is no god". I don't think it's possible to know the non-existence of anything in our world for sure (mathematical constructs can indeed be proven to "not exist").
I think there is a big difference between the statement "There is no god" and the statement "I know with certainty that there is no god". I don't think it's possible to know the non-existence of anything in our world for sure (mathematical constructs can indeed be proven to "not exist").