Sleepy, you said: But if we are not created and have just evolved as part of a natural prosses why should we asume that our brain should have any grasp on a true understanding of things.
The brain and the human mind are products of millions of years of natural selection and are adapted to the environment we live in. Suppose that a primitive antropoid sees two lions getting into his cave but only one getting out, what would he conclude? Well, you bet that those who couldn't figure there was a lion still inside are not among our ancestors. That's how our innate sense of arithmetics evolved. The problem is, our senses are only adapted to our environment (ie: macroscopic phenomena on Earth). We can still understand very well certain phenomena in the Universe; even Relativity is understandable, although counter-intuitive. Quantum mechanics, on the other hand, is just sets of equations on paper; it's comprehensible but not understandable. Most likely, there are things in the Universe that cannot even be mathematicized and thus will always be beyond our capabilities of abstraction and comprehension.