II. To the Initial Arguments
22. To the first argument [n.3] it is plain that that was necessary at the beginning of the human race, namely that a contract be made in the first degree, yet in transverse line, not in direct line.
23. To the second [n.4] I say that the friendship of those of the same blood is different from the friendship of spouses. The friendship of those of the same blood, especially in the direct line, is one of reverence, as to descendants in respect of superiors, and in respect of a certain rule and presidency. Conversely, the friendship of spouses is without such reverence, rather with irreverence, so much so that he who more sincerely loves his spouse more hates that reverence in her, not only from himself but from anyone else; and therefore I concede that friendship does dispose to marriage, but friendship of a different idea altogether from that which is between those of the same blood.Scotus gives no response to the third argument [n.5], perhaps because it is in effect answered by the answer to the second argument [n.23], that the friendship of those of the same blood is not the friendship required for the good of matrimony that is faith or fidelity. Or, it could be said that another good of matrimony, the good of offspring, is harmed if the parents are close relatives, because of inbreeding, whose effects must have been known in Scotus’ day (they can be very obvious, in other animals as well as humans), though not the biological causes in the genes. In the case of Adam and Eve, however, on the supposition (which Scotus of course makes) that they were the first humans and were made perfect, because made directly by God, there would be no defects in the gene pool, which would have taken time to emerge. So Cain and others of Adam’s and Eve’s children could have children together without fear of such defects.
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