I recently had a friendly but rather erudite discussion on whether "game of thrones" is a cool show. I think it is. Needless to say there was disagreement, and it got me thinking...
...Why do we believe what we believe? It applies to life's mundane questions, like, "Is game of thrones a cool show?"or to life's profound questions like, "Is gay marriage right?". We like to believe our beliefs are rational, but if we honestly trace them all the way back, our most fundamental beliefs, especially moral beliefs (what's good, what's bad or what's right), are either instinctive ( that we are born with) or what we were socially and parentally conditioned to believe as children. The "mature-adult beliefs" are not necessarily truths we reach by rational deliberation, but are often rationalization of our beliefs by deliberation. Sometimes the belief itself might be logical and rational, but that's not primarily why we believe it.
If you teach a child, it is a sin to stare at daisies, he might grow up to live with perpetual guilt as he can't help but like daisies. Instead of questioning and rejecting the ingrained irrational belief, he might go on to justify the guilt and the belief with scientific" or "theological" rationalizations like, "daises are poisonous", or " daises are the devils flowers". It takes a tremendous amount of cognitive and emotional effort to be critical of instinctive irrational beliefs, which are not life affirming, and to change them. We are capable of rationality, but more often than not we are predictably irrational or arational.