[@Meta][@Disdain] I completely agree with both of you. As far as human logic goes and the things we can perceive, you are both right. But I'm thinking of the existences and ideas we can not perceive and as such can not even begin to understand. 

A square circle, as far as we know and by the limits and definitions that we have placed on each individual geometrical shape can not exist because it contradicts itself. But the definition alone is abstract as everything that we have placed a value or meaning to. Even if God created a form like that, our minds could simply not understand it. That's where I'm coming from. Humans, 3 dimensional beings who try to give meaning and limits to things above them, beyond their understanding using their logic is pure arrogance. Yes, you may call them theories, like everything we know about the universe and how things that we cannot see or touch work but don't go and call them definitive truths. For somethings, even all the vocabulary in the world couldn't begin to define them since we ourselves cannot understand the concept.