First off, you're argument has exactly zero to do with evolution, what you are discussing in Atheism. Not all Atheists accept evolution not all those who accept evolution are Atheists.
Now, we've got that small detail out of the way let's deal with your question.
Philosophy 101: we
Know nothing. Squat. Zero. I've put
Know in bold with a capital because I mean it in the very specific sense of know with absolute, 100% certainty and can demonstrate this to be so. I'm amused by those who casually throw around meta-physics but seem to have missed this really basic point.
The problem with this approach is that in the world view it exists in (atheistic), unproven assumptions are not allowed.
This is not true. I accept the existence of a real world, that can be known by the application of our senses as an unproven assumption. In effect, an axiom of knowledge: Observation and induction work.
It wants to use the laws of science and logic, but in doing so it presupposes the existence of such things.
There are no absolute 'laws of logic', they are derived from the only real absolute: the real world. We accept them because they succesfully model the way the real world works at the Macro level that we deal with. That is all. So while the 'laws of logic' cannot be known to be true in a absolute sense we can demonstrate their truth by induction, in effect we can only use deductive techniques because they can be demonstrated inductively.
You are falling for the most common of Theistic falacies - that others worldviews work like yours. Sorry, we don't. We don't see the world as being an absolute thing we know about, but the knowledge we have works now, and has worked in the past. If it ceases to work, we'll change it. Life goes on.