In the midst of an interview discussing how we argue about God, Keith DeRose asserts that “neither theists nor atheists know whether God exists”:
It was about God, wasn’t it, that Kant famously wrote “I had to deny knowledge in order to make room for faith”? Whatever it does or doesn’t do for faith, my denial of knowledge here makes room for reasonable views on both sides of the question of whether God exists.
I don’t think the arguments for either theism or atheism lead to knowledge of their conclusions. But there are arguments on both sides from premises that someone might reasonably judge to be plausible. If you find it quite probable that God does not exist, I think it’s perfectly possible that you are reasonable to think as you do. But this doesn’t mean that someone who thinks it is likely that God does exist can’t likewise be reasonable in holding that position.
To know that God does (or doesn’t) exist, you have to show that there are no arguments for atheism (or for theism) that a reasonable person could find plausible. But to support that claim you would have to have better critiques of all those arguments than I’ve ever seen. In my view, it’s more likely those who claim to know whether God exists — whether theists or atheists — are just blowing smoke.