I thought I'd comment though it wasn't addressed to me.
Since atheists (well, those I'm referring to) don't have a concept of god/deity it would make no sense to ask evidence for something without any knowledge of some sort of what they need evidence for.
But that's not atheism, that's just undetermined skepticism. If one says "I'm an undetermined skeptic regarding the existence of any gods" we would not then ask them to defend a position they have not yet determined to hold. But if one proclaims themselves to be atheist, they are proclaiming the
antithetical position to theism which is the proposition that a God/gods do exist in a way that significantly effects humanity. So, of course, the antithetical to that proposition is that such God/gods
do not exist in any way that effects humanity. So if one does not want to be called on to defend atheism, they shouldn't proclaim themselves to be atheist.
If they are atheist, however, they should be prepared and willing to defend their antithetical position to theism, just as they would expect the theist to defend his pro-position.
See how reasonable and sensible this is?
So, the best way to look at it when someone says they don't believe god exists is that they a. have no clue what god is, b. have no clue what criteria one would use to derive that god's existence, and c. how that criteria would best fit the god they are unfamiliar with.
There is nothing to "look at". What one
does not believe and
does not assert is irrelevant to everyone, including even himself. There is nothing to consider, or discuss. It's empty rhetoric.
The problem is an atheist would need to know what god is in order to determine whether there is such thing as evidence for it to begin with.
The problem, here, is the intent to negate a position in advance of it's being proposed. It's just plain dishonest. Either your mind is open to a proposition or it's not. If you are an undetermined skeptic, then your mind is still open to the theist proposition. If you are an atheist, then your mind is not open (to any theist's proposition). And I find that a great many self-proclaimed atheists are trying to claim both roles at the same time. And that's both dishonest, and frustrating for any theist to try and deal with in discussion.
This is what this thread is trying to address.
I assume there are atheists that genuinely believe there are no gods and if evidence pops up, like you said, they probably wouldn't detect. How do you know the difference between who is a "real" atheist (or theist) and who is not just from the fact they don't believe (or do believe) gods exists?
Well, if they are honest, all I have to do is ask. Unfortunately, many are not. And so I have to try and determine from discussion whether or not their minds are still open to the theist proposition, in some form, or they are just out to negate anything I propose.
I am a theist, and even I do not accept many of the god-concepts that other theists propose. So I don't expect anyone to be open to them all. But an atheist is not going to be open to any of them, because atheism is the determined antithetical position to theism. And the atheist should be honest about this. AND they should be willing to defend their atheism to the same degree and by the same standards that they demand the theist to defend, his.