Rawel Singh seems to have been over imaginitive in his attempt to explain atheism.
The simplest explanation is that atheism is simpler than religious belief. You avoid having to be involved in weekly ritualistic exercise, and perhaps other more frequent rituals. You can watch that football game, or play golf, instead of having to attend church.
Others, I am sure, have made a conscious decision. They have examined Christianity, and found the evidence for its foundational principles to be lacking.
I doubt Rawel Singh's view about ethics. The atheists I known are very moral people, and I have had serious questions about the morality of some of the Christians I have known.
Maybe the question should also be turned around. What is the explanation for being a Christian? I would guess that in many cases it is simply a matter of going along with family cultural traditions. Doubtless some have made conscious decisions based on the Christian message, but I suspect those to be a minority.
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