I'm a Gnostic Atheist, however with all due respects to my fellow counterpart atheists, I find that under their reasoning, they have omitted or dismissed apriori reasoning outright. I'll give an example to bring light to my position:

I know that all bachelors are unmarried and that a square circle is nonexistent. I don't need to go in search for all bachelors in the universe to interview to make that claim, nor must I go beyond a greater sense data to know this. I also don't need to search the entire universe - or outside thereof - to confirm the non-existence of a square circle. Those 'negatives' as is often said, that in them of themselves are falsifiable.

These concepts in it of themselves are fallacious and thus cannot exist, because existence requires consistency. Through apriori reasoning, we can shed light on the validity of concepts or the lack thereof, without actually acquiring empirical sense-data. In the same light, I know God does not exist because the very concept in its essence is illogical. And thus, likewise, cannot exist because illogical 'things' cannot exist in reality.

Many atheists are very keen on saying that God is illogical and irrational, however many that do say that, so often have a "might" that the illogical "may" exist, implicit to their lack of belief. I find this cowardice because it is not asserting oneself to acknowledge illogical things cannot exist in reality, since that which exists requires consistency. Also, agnostic atheists have a problem with 100% certainty claims, however the epistimological claim that " You cannot know for sure if God exists or does not exist " is in it of itself a 100% certainty claim. They should have no problem with Gnostic atheists making 100% certainty claims on the basis of logic, if they themselves make 100% certainty claims on, to what is them, the basis of logic. It is hypocritical.