If something is in principle, by definition, *unknowable*, then it seems to be in principle, by definition, *nonexistent*; is there a term for this thing?
This is why there is no real difference between agnosticism and atheism. If God is really unknowable as the agnostics claim, then he is basically non-existent as atheists claim. But if he has revealed himself in time and space, as most religions claim, then he does exist.
While I do think there's not really a meaningful difference between atheists and agnostics, I also meant something different in my original tweet that I'm realizing now I should explain in more, better words
There is a profound difference between the two. We agnostics understand that our mind is limited, that we do not have access to certain perceptions. An atheist has faith that his mind is the same as other minds and has faith that what which cannot be perceived does not exist.
Agnosticism is simply an epistemological stance, i.e. that the existence of god is not a known fact. Nobody *knows* there is a god. Atheism is the rejection of belief in a god. It's a stance based on the known facts.
We are all agnostic. But some agnostics are atheists.