While picking up a prescription in the local drug store, I noticed a book on a rack of Christian literature entitled "Heaven is real." Which started me thinking ... .
One possible explanation of religion is that it is wishful thinking. People do not want to die, so they want to believe in life after death. One problem with that explanation is that several of the most successful religions include both Heaven and Hell. The quiet of the grave does not sound very attractive compared to an eternity of bliss. Compared to an eternity of torture, on the other hand, there may be much to be said for it. So why are people attracted to a system of belief that offers the possibility of the former but also the risk of the latter? How high do the customers have to believe the risk is before they would prefer not to buy? Putting it in the jargon of my field, what are the relative Von Neumann utilities of Heaven and Hell?
Heaven and Hell make much more sense as an incentive system, promised reward and threatened punishment as a way of getting people to follow the dictates of a religion. That is a good reason why some people would want others to believe in them. But it does not explain why people choose to themselves believe in them. Perhaps wishful thinking is not, after all, the right explanation.
For an alternative explanation, see an old post
of mine that started with the same puzzle.