I think many of us non-believers need to take a different approach to this subject, even if fellow believing civillians tend keep asking the question--Why don't you believe? every second of the day.(Kind of like asking why are you "YOU"?) Religion is a system of held beliefs, codes, and ethics. Also, it tends to group the believers in a group identitiy that they are both apart of and add to. A manner of looking at it from this point, religion is a cultural and personality shaping tool in which "Ideal citizens" are created. Of course, when you look at the end results, not all practioners resemble anything "ideal". In fact, they are more like an average person with a chosen method of approaching the world. Yes--Religion is a choice. Of course, I can be wrong. if anyone else like to add what they think religion is, please comment.