When and where did atheism first start ?

[Losty]

I’m not sure I agree with you here.
Atheism doesn’t mandate that you disbelieve something.
Only that you don’t believe it. Which I don’t think is actually the same.
You may not actively disbelieve every future scientific theory, but
you certainly don’t believe them either.

IDK about you guys, but I disbelieve religious doctrines. That doesn't mean "I believe they aren't true." But it DOES mean, that I've examined them, come to a conclusion about their plausibility and "actively" decided not to believe them. I assume that anyone who categorizes themselves as an atheist has done something similar. We don't generally refer to people as atheists because they have no knowledge of religious doctrines.

I suppose also that we have some ideas about "active" disbelief and "passive" nonbelief. The distinction between these two categories is unclear. Who is a "passive nonbeliever"? I consider myself an agnostic atheist because I have no knowledge of any gods that exist. But I've looked at religious claims, and I DO NOT believe them (what I call "disbelief"). Am I rather a passive "nonbeliever" because of my agnosticism?

I also consider myself an agnostic atheist because I have no knowledge of any gods that exist. But I not only disbelieve religious doctrines, I also actively believe they are not true. I could never say that about a god. I can’t say “I believe no gods exist”, but I do believe that all religious doctrines that I’ve been exposed to are untrue.

I wasn’t saying that you can’t disbelieve. Only that atheism does not mandate that you disbelieve. By most definitions a simple lack of belief will do.