I've been forever scarred - in a good way - by the James Burke series "the day the universe changed". In I think the penultimate episode he explains as we watch

I've been forever scarred - in a good way - by the James Burke series "the day the universe changed". In I think the penultimate episode he explains as we watch a dramatization of a witch being tried and burned at the stake that the people perpetrating the horrible act truly believed that they were doing a good thing. That their reality included witches and Devils and gods and that they were doing this woman a favor for her immortal soul. It sounds rediculous to us today but sending someone to be medicated because they don't adhere to your particular belief system seems right in line with that kind of thinking. (To say nothing of religions that practice exorcism, Rebirthing and eschewing gluten. ) Personally I wonder what beliefs we hold today will be absolutely appalling to our descendants 400 years from now. Probably eating meat (and I say this as someone that is in now way pro-veg, and I eat meat all the time - I just suspect we will find that our current working theories of animal behavior will prove that we are morally responsible for great pain in other sentient beings.) because our society keeps it acceptable in our perceived (or imposed) reality.