This post is lifted from my response to this blog post: On Agnosticism vs. Atheism
I think about this idea (a lot). My approach is from the angle of how the brain works.
Something everyone (everyone who is ok with natural selection) can agree on is that the brain evolved to (at least) enable organisms that move around to successfully negotiate their environment.
Success in terms of natural selection means persistance across generations.
A good basic definition of the brain is that it is an organ that can take in sensory inputs and turn those inputs into motor activities that allow the organism to get around.
From a algorithmic standpoint the brain has to model the sensory input in such a fashion that it can make good enough predictions of the future to allow the organism to successfully get around.
On thing that can not occur is that the algorithm goes into some sort of infinite regress, or loop. It must always resolve things. Getting 'stuck' when considering how to move around the environment can result in diaster which the prevents persistance across generations.
There is a great book out, "The Believing Brain" by Michael Shermer, that goes into just how far down the rabbit hole of resolution the human brain can go. One of the main points of the book is that the brain evolved to make snap judgements on poor data because making the error of false positive when analyzing risk is selected in favor of while the error of false negative is selected against because it can result in the organism becoming lunch for some other organism.
Religion and and the Scientific Method are seen to emerge differently. Religion is a very natural and even hardwired attribute of the brain. We have to resolve things, we can not become stuck so we make stuff up when necessary to accomplish this.
The Scientific Method which is by definition more methodical, does not naturally emerge because it requires a lot of safe leisure time to execute.
It is very difficult to shed the evolutionary heritage that gives rise to concepts like God and other such fantastic beliefs because these keep our brains from 'locking-up' and are deeply ingrained in how the brain works.
So when posed the question "Does God Exist?" my response is: "There are lots of answers to this question and here is how I rank them, in order correctness (least to most):
1 - Yes
2 - No
3 - I do not know.
4 - I do not understand the question.
5 - It is worse than that (response 4) you do not understand the question either.
6 - Let me tell you how the brain works and this will explain why the original question makes no sense."