I have recently come to re-examine the moral issues attached to the arguments about and prohibitions of incest. They seem to fall into three distinct categories. The first is the reproductive problems of historical “consanguinity” and “affinity”. The second is the element of trust and of power. And the third is the personal psychological disposition of intimacy.
In the first instance, we have evolved our current morality based on biblical prohibitions of “consanguinity and affinity”. The ancient people, unaware of the scientific intricacies of genetics, were however aware that interbreeding within family groups had a disposition for producing children with a variety of physical ailments, and they considered any lack of health to be an indictment from God. Therefore, NOT to commit incest, which would lead to healthier children, must be the theistic directive. Thus they evolved their prohibitions based on consanguinity (‘being of the same blood’). At the same time, they were also aware that if a child was created through affinity (‘connection’), there would be issues over who owned the child, and this could cause problems over the inheritance of property and of any birth right. If a man had sex with his sister-in-law, the child would be his, as the father. However, at the same time, because a man and a woman “become one” at marriage, HER child was also the child of the brother. So, whose inheritance does the child get? If the brother was the first-born, do the rights of primogeniture pass on to the child, even though neither of the biological parents had such an entitlement?
The question must now be posed, what happens in circumstances in which there is no reproduction of children, such as in an age in which contraception is widespread or in which the relationship is homosexual, or in which the woman has passed menopause. Do consanguinity and affinity have any moral relevance there?
The second argument has to do with trust and power. For the same reasons that a teacher is not allowed to have a relationship with a pupil, or a therapist or doctor with a client, irrespective of the age of the participants, we tend to frown upon any relationship in which there may be any form of coercion based on the trust that one party has in the other, or of any power which one may exert over the other. This sort of trust-power situation occurs in most families. But it is not necessarily universal. If a brother and sister enter into such a relationship when they are both in their late 20s, does such a situation exist? I estranged myself from my family for over 20 years. When I reconnected with them, I discovered not only that I had numerous nephews and nieces, but that the youngest of them was 18 years of age. If we were to enter into such an incestuous relationship (and since I have met him only once, no, this is not an admission that such a relationship exists), could I be said to be able to exert a familial power over him or that he has developed a sense of trust in me based on a familial connection and history? The fact that we HAPPEN to be uncle and nephew is incidental and irrelevant to any concept of power or of trust. We simply KNOW each other and, with no deeper significance, happen to be related in terminology, rather than in effect.
The third argument is about familiarity. Some people simply cannot imagine having a type of physical and sexual intimacy with someone that they have been as close to as their own sibling or relative. (This beckons the absurdity, Can one have sexual intimacy only with people with whom one is NOT close?) This has to do with a personal psychology and has nothing to do with morality. What you can or cannot imagine has nothing to do with what is right or wrong. Some people cannot imagine eating cat, but does that make the cultural decision of some people to eat cat morally wrong, or merely culturally different? Historically and sociologically, there have been some societies for which the concept of incest has not been condemned, such as the Egyptians or the Germanic Hohenzollerns. In others it has been condemned, but the limitations and definitions of who fits into the banned group have changed. Some people regard cousins as being too close, and yet Queen Victoria married her own cousin. Jerry Lee Lewis married his own 13-year-old cousin. Many people in the Bible married their own cousins. Can we rationally argue that “I just can’t imagine myself doing it” is a sound basis for a moral imperative? A personal ethical one, perhaps. But a moral one, with the full weight of legislative authority, that becomes a different question.
We can clearly see that there are some circumstances in which incest cannot be morally opposed based on either the traditional Christian or the pragmatic arguments. Legislation must deal with the majority of circumstances, and certainly in so many cases incest is improper. Yet the law has the ability to allow people to argue a reasonable defence, such as no children, and no trust-power issues. And yet it remains entrenched in a biblical past, evolved to deal with issues which are no longer as universal as they used to be.