how do u think about Incest?

1smokewater2014/09/26(金) 16:18:29.83
sry 4 my writing on English,though i can tell Japanese, i couldnt describe my question on Japanese.
Okay,at first ,incest is considered not being tallied with moral principles.Second,we all know that the child who incest have more chance to have Genetic Diseases.
but we all know that moral principles is coming from the behavior that would benefit the most people.In ancient,people cant bear incest cuz they would have children with Genetic Diseases.So they forbid incest to benefit the most people.
But now we have better science,parents can have test about Genetic Diseases and prevent the harm.At least,if the child have Genetic Diseasesm,the society can afford that, so how can we oppose the incest?
yes,we can say incest not accord to moral principles,but why incest not allowed to moral principles?That's the key question.
i dont have any sisters, and i dont support or oppose insest in personal,i just wonder what the reason the society oppose incest?