When incest is brought up in conversation it is normally met with utter revulsion. What are the main reasons for this and are they connected with morality at all? Is incest immoral?
From an evolutionary point of view the avoidance of incest as well as communal condemnation makes a great deal of sense. If you have children with a close relative then there’s a higher chance of the children dying at birth or suffering from some form of congenital disease that may have previously lain dormant within a family’s genes. The chance of this occurring decreases as relatedness decreases, though it never reaches 0 (I will comment on this later).
For instance, if one’s father was heterozygote (had two different alleles) for a gene that when homozygote (having two same alleles) gave its owner a congenital heart disease that was terminal. That is to say that he had one normal allele (dominant) that prevented the expression of that disease, as well as one deleterious mutant allele (recessive) that when in duplicate (homozygosis) gave its owner the disease. If he has two children, there is a 50% chance that either child receives the recessive allele. If both children end up heterozygote for this gene like their father and decide to have children together there is a 25% chance that their child will receive 2 of the recessive alleles (homozygosis) from its parents, and the will then suffer from the disease.
It’s almost a certainty that everyone has a recessive allele in his or her genes that would express a disease if it were in duplicate, homozygosis. This is one of the main reasons it has become culturally unacceptable in almost every corner of the globe to commit incest.
But is this a moral issue? Incest doesn’t necessarily entail the production of children. Incest is the act in and of itself and not the result. So if two consenting adults for whatever reason decide to delve into an incestuous relationship without the wanting of children, taking adequate steps to actively avoid this. Is this still immoral?
You may argue most incestuous relationships aren’t consensual. You may be right, but such relationships aren’t immoral because they are incestuous. They are immoral because one person is taking advantage of the other. Such relationships are immoral because of the abuse incurred on one of the persons involved, physical and/or psychological. Whether they are related or not isn't what defines it as immoral, it's the abuse of power used to hurt another.
Thus I don’t believe it is immoral for consenting adults to enter into and incestuous relationship, assuming the absence of abuse and if they avoid having children. However, that raises another question. Is it immoral to have children even if there is a higher than average chance that the children will receive a debilitating disease or could die at birth?
There are many people out there who have acquired homozygosis for certain congenital diseases. There are also many people who know they may carry one allele for a specific disease that has run through their family, some may know that they carry it. There are women out there who have trouble finishing pregnancy, where their children die early on, though they continue to try to have children. There are also plenty of women who cause their children to suffer disease and addiction when they use drugs irresponsibly while pregnant. Nonetheless, in most of the aforementioned cases it's not regarded as immoral to keep trying to have children, let alone illegal for them to do so. Yet it is illegal and judged immoral for close relations to attempt a similar act, where the fetus or child is at the same amount of risk.
Who would dream of denying a couple the ability to have children even if there's a large chance their children will be disabled or have a disease? Especially if the parents are willing to care for the child anyway. Who would tell these people that it's immoral for them to have children knowing that there’s a risk of disease or disability? If it’s not okay for close relatives to produce children because there’s a higher risk of disease or disability, then why is it okay for people to do the exact same thing with non-relations? If we were to follow the same line of logic, wanting to prevent children being born with disease or disability, then it would be as illegal for non-related couples carrying bad genes as it would for closely related couples.
I just find it a little bizarre that two couples could carry exactly the same allele for a disease in each one of their genetics. Both couples, should they have children, would have the same 25% chance of having a child with the disease. However, if one couple is brother and sister it is a jail-able offence, whereas for the other couple it is perfectly legal.
It would then be reasonable to conclude that the resulting act of an incestuous relationship by consenting adults, even if they choose to have children, is not in and of itself immoral. Especially when you consider that a non-related couple with the same chances of passing on the disease are considered far from immoral if they choose to have children. Incest may not be immoral, however, it is much more likely that circumstances surrounding incidences of incest make the relationships immoral when compared with non-incestuous relationships.
What are your opinions?