One of my favorite quotes is when Richard Dawkins described how evolution made one "an intellectually fulfilled atheist". Here is the quote.
I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist.

In fact, I believe that atheism is logically tenable, but it is impossible to be an intellectually fulfilled atheist or theist. Why? Because however many people want to say we have the ultimate answer, we do not. Although you have probably been through this many times if you are familiar to the god debate, I feel a refresher would be nice.

How were we created? Evolution
How did the first life come to exist? Abiogenesis
how did the planet come to exist? Core accretion.
How did the universe come to exist? The big bang
What made the matter in the big bang? It existed eternally, or for infinite time. Sometimes quantum flunctuations are put into this explanation.

But we keep going back, if somebody invoked an idea like the multi-verse that existed eternally, then how could this have existed eternally? Why does it exist in the first place. Does it "just" exist. Furthermore, why are the laws of physics the way they are, why are they not crafted differently. Furthermore, why is their existence at all? If their is nothing, how is existence added, which is an attribute. Quantum Flunctuations is another law that "just exists". If you attempt to explain why Quantum Flunctuations exist in the first place, then you must exist why those laws exist which caused quantum flunctuations, and so on and so on. It may appear that I am making an argument for god, but how could even a god exist for eternity. God is supposedly inttelligent, how did he gain his intelligence? Did he just, have his intelligence which is also an attribute for no reason at all. How is god eternal yet still thinks which requires time? No, god is a fully human explanation that does nothing but add more complexity to these deep questions. Basically, infinite regress takes place in almost all laws of reality, causing reality to become ultimately illogical. In fact, it causes everything to become illogical. One cannot be an intelectually fulfilled atheist, although atheism is more logically tenable then religion. However, we must all take a break from the god debate and remember that neither religion nor science can explain the mystery of reality...yet.