The problem with incest is not actually to do with inbreeding, though the degree to which human inbreeding is deleterious is both significant and well studied; see A Background Summary of Consanguineous Marriage. Inferences of the consequences of selective inbreeding taken from domestic animals, or from genetically very different mammals such as rats, should not be applied to humans.vivaxardas said:Actually, in-breeding is a well-accepted technique with animals, as, for examples, horses. They do it to strengthen good genes. In-breeding does raise a chance of receiving two alleles of some recessive bad trait, but not every family carries them. This problem is more prevalent with some small isolated human populations, when a bad trait appeared through mutation, and spread. People from such groups are encouraged to have a genetic screening before marriage. But even if they do not, or decide to marry anyway, with a hope to get lucky, it may be dumb, but not evil, not seen as bad as incest. So just a chance of genetically-defective off-spring is not really an explanation.
Plus, people have sex with a purpose of reproduction how often, 5-10% of a time? What was the last time, if ever, did you have sex in order to have kids?/>/>/>/>
As I remember from one of anthropology classes, kids who grow up in the same family, even if they are not related by blood, tend not to perceive each other as ex partners. Probably, psychology + biology. Also it may be a historic-religious thing: sex may be still seen on a sub-conscious level as sin and aggression, and family members should defend and take care of each other, not be aggressors. In other cultures insect was quite all right.
Disclaimer: don't think I am a weirdo, please. I have no personal interest in incestuous relations, cannibalism, or any other taboo-breaking behavior. I am simply curious how and why these taboos arise in our culture.
The problem is that incest is not what we are pretending it is. It is actually a form of sexual abuse of children. Most incest is not between consenting adults (which we could assume Foltest's to be). The most common form of incest is rape of a daughter or stepdaughter by a father or stepfather, followed by rape of a child sister by an adult brother.


