Thread:Jester of chaos/@comment-27729149-20150602022947/@comment-1705775-20150810210444

incest is not an instant MEH.. there were cultures were incest was part of the norm.. heck, there's still cultures where incest is regularly practiced.. it's really more to do with it being a social stigma (and in some places a legal issue).

incest is a taboo but just like cannibalism it was (and continues) to be practiced by other cultures and is a case of "cultural differences".. many monarchies believed incest kept their blood "pure" (despite genetics proving this.. well.. untrue) and to a lesser extent there are still many tribes / clans etc that want to marry within "their own kin".. incest with cousins is extremely common, those involving siblings are rare (but happened in Ancient Egypt among royalty) but those between parent and child have always been "crossing the line" (even Ancient Greece did not approve of parent / child incest.. for pretty obvious reasons).