If heredity were not overwhelmingly more important than environment, you could teach calculus to a horse. — Robert A. Heinlein

It is hard to shake off any taboos a child is indoctrinated with in his earliest years. Even if he learns later that they are nonsense.

Natural laws have no pity.

Stupidity cannot be cured with money, or through education, or by legislation. Stupidity is not a sin, the victim can't help being stupid. But stupidity is the only universal capital crime; the sentence is death, there is no appeal, the execution is carried out automatically and without pity.