[Verginius Rufus]

Every society has condemned incest, but the boundary between what is permitted and what is forbidden varies. In ancient Athens, half-siblings could marry. In the Israel of King David, Amnon could have married his half-sister Tamar (but after he raped her he no longer wanted her--which meant that she had no future, and pretty soon he didn't either because of Absalom, Tamar's full brother).

England's Queen Mary I married her first cousin, and Queen Mary II also married her first cousin. Both marriages were childless.

[elcid1970]

But again, what is the cumulative effect of inbreeding & incest in the right here and now?

I say it is Islam, which comes against us as the Destroyer. Its victims are now piling up in anonymous heaps as were those of the Holocaust. We in the West are as yet mostly blissfully unaware. God help us for that.