...........therefore............ Society must be wrong to prohibit family members from having offspring with each other which allows otherwise (often VERY detrimental) passive genes to become dominant, right? 'Cos that would be controlling who people can and cannot mate with - a form of eugenic control.
..........therefore............. if there was a culture that promoted and approved of close family inter-marriage - say cousins - then despite the FACT that they have a statistically higher % of deformed offspring, it would be VERY unwise to state or publish these facts - bacause that would make you a supporter of Eugenics, which, as all "truly intelligent" people know, is a nonsense supported only by Nazis and Satanist and Racists, right?
....watch the hysteria....