If you believe in random selection and physics and all that I'm sure you can estimate the probability that something like us, here, today, can exist. Following general atheist belief and scientific proof gives me a probability which is essentially zero. Thus it would be only logical if there was something which privileged our development.

edit: In fact, if you now answer "but the probability is not zero, there is the chance that all that happened by accident" I agree. But I hope you see that this argument would not be valid for someone who claims to be on the all-proven side of the world, because, as we just calculated, odds would be so much against him that this would be "blind belief".