The overwhelming response to my defence of incest on GB News has been one of disgust: I’ve been called a pervert thousands of times over. It’s water off a duck’s back to me.

What is extraordinary is the absence of decent arguments against my liberal position. If reproductive and non-reproductive incest are so bad, why do people resort to personal attacks as opposed to moral arguments? There are two reasons: our evolution has predisposed us to viscerally reject incest; and the moral arguments against incest come unstuck because they risk dreadful consequences.

After stonewalling me at dinner last night, my mum gave the same response to the same question

I fear that the main objection mounted against reproductive incest could ultimately lead to dreadful outcomes, such as state enforced eugenics and even the sterilisation of disabled people.

When the social psychologist Jonathan Haidt asked focus groups about a hypothetical brother and sister who had doubly protected sex on holiday, he found their response to simply be that it was wrong, even if they couldn’t explain why. After stonewalling me at dinner last night, my mum gave the same response to the same question. This intuition is rooted in our evolution which has predisposed us to be this way; it seems likely that those who didn’t have a disgust response to incest may have died out at a greater rate if their children were more susceptible to genetic disorders.

But we must be honest that our objection to incest is not rooted in some moral truth; it’s a biological quirk. During my appearance on GB News, the hosts Andrew Pierce and Miriam Cates argued that reproductive incestuous marriage is unacceptable because of the risk of ‘unnecessary genetic deformation’. The debate was in response to an attempt by a Conservative MP to seek a ban on cousin marriage. But if this ban is aimed at reducing the risk of birth defects in the children of those born into such relationships, then must we also crack down on over-40s from reproducing given that they have too appear to have a heightened risk of having children with birth defects? Few would say that should be the case, so we should be wary of accepting a moral argument which requires it as the next logical step.

‘Individuals should be free to marry and have children with whoever they want…’

Writer, Charles Amos, joins GB News to describe why he believes individuals should be free to form a relationship with anyone, including incestuous relationships with cousins or siblings. pic.twitter.com/vxXv7Xnfli

— GB News (@GBNEWS) December 19, 2024

There’s also another point to make about the children of those born into incestuous relationships: even if these babies are born with birth defects, it seems implausible to say that the harm they may have suffered is worse than if such relationships were banned and they didn’t exist at all. Surely existence with a birth defect is better for them than nonexistence? Cates cannot talk about most of the children of incest having ‘disadvantages’ and propose getting rid of those by banning incest, because, in so doing she stops the specific children of such incest from a specific sperm and specific egg from ever existing. This means that they can never benefit from the elimination of the disadvantages.

What I think Pierce and Cates are getting at is that it is morally better for children as a class to be without birth defects even if no particular child in that group has their interests improved by it, as banning incest ensures the creation of different people.

But if the freedom to procreate can be restricted to improve the genetic stock of the population, despite no one being harmed by incest, we risk treading a dangerous path. It might not be long before some suggest that disabled people with inheritable diseases be sterilised. Why not go further, these people might say, and plan the reproduction of the population to ensure future children can have the best lives possible? A person who has rallied against incest can’t cry freedom if they oppose such arguments because they’ve already denied this value in banning incest.

My concerns here aren’t hypothetical. In the United States, the Supreme Court verdict in Buck v Bell in 1927 upheld a state’s right to stop some people from reproducing; as a result, 70,000 people were forcefully sterilised. This is the potential conclusion of the reasoning employed by some of my critics. This is wrong, hence, the moral reasoning supporting the incest ban is too.

Why is it wrong though? The deep problem with compulsory eugenics is that it denies the moral fact that each individual exists for his own sake; he does not exist to serve the higher purpose of creating a fuller world of better people. Yet this is being implicitly denied by those against incest. They’d rather children of cousins or siblings didn’t exist to enjoy their lives because, their very existence does not help advance this better world. But why? So children can have higher scores on maths tests, run faster in sports races, or not age as poorly in their twilight years? Fine things, I admit, but promoting them does not warrant breaking up marriages because the potential children of them might bring down the average height or total quantity of such things.

Defending incest may be disgusting, but as F.A. Hayek, himself third-cousin-married, once wrote: ‘Freedom necessarily means that many things will be done which we do not like.’ Underneath some of the opposition to incest appears in my mind to be an unspoken support for compulsory eugenics; these people are likely to be oblivious to its presence, but there it lurks nevertheless. In a liberal society, the individual must be free to pursue their own good in their own way including to marry and have children with whoever they want; a future full of better people be damned. Politicians should accept this wisdom and stay out of the love lives of the people – after all, it’s none of their damned business.