“What, precisely, is so bad about sex between adult siblings, bestiality, and the eating of corpses? Most people insist such acts are morally wrong, but when psychologists ask why, the answers make little sense. For instance, people often say incestuous sex is immoral because it runs the risk of begetting a deformed child, but if this was their real reason, they should be happy if the siblings were to use birth control – and most people are not. One finds what the social psychologist Jonathan Haidt called ‘moral dumbfounding’, a gut feeling that something is wrong combined with an inability to explain why.” Rest of the article by Paul Bloom here in The Guardian.
