Why are eugenics wrong?

One would have thought that, given how the enthusiasm for eugenics in the early 20th-century America, and how it led to forced sterilization laws, as well as how eugenics theory led to the Holocaust in Europe, this question wouldn't even need asking. But obviously, it does -- and it does because a certain kind of liberal (and, I suppose, libertarian) now believes that as long as eugenics is voluntarily chosen, it's morally acceptable. Here, via Cheryl Miller, is Yuval Levin explaning what's wrong with that position:

But the great danger of the old eugenics movement was not that it empowered government. Far more dangerous was its undermining of our belief in human equality and our regard for the weakest members of our society. Any number of American thinkers, writers, and jurists, including H.L. Mencken and Oliver Wendell Holmes, Jr., took the insights of Darwinism to mean that, in Mencken’s words, “there must be a complete surrender to the law of natural selection,” and that society was morally obligated to rid itself of the congenitally ill and the disabled.

Today, the idea that it is morally acceptable to "improve" upon human life through genetic manipulation, paves the way for a time when it will be morally compulsory to do so. This way of thinking makes it possible to consider weak, the disabled, and anyone who deviates from the standards dominating society in a given time and place to be placed in a lesser category of humanity. If I were a gay person, or a disabled person, I would be very afraid indeed of the rise of "liberal eugenics."

As Levin recognizes, the moral harm of the eugenic idea lies not primarily in the use of state power to mandate and enforce eugenic measures. It lies in the way eugenics trains our minds to think of the value and dignity of human life being relative. You can be quite certain that the characteristics that define what the You-Know-Whats called "life worthy of life" will be determined by the powerful in any given society, at the expense of the weak. To accept that life is not worthy of life in and of itself is to open the door to hell. I'm quite serious.

The thing is, every single one of us struggles to keep the full humanity of our neighbors in front of us every single day. No one -- conservative, liberal, apolitical -- is immune from the temptation to denigrate the humanity of the Other. Look at the phrase ~tv used in a combox comment -- "Why is it such a horrible thing to ask people who shouldn't breed to not breed?" If the point is that people shouldn't have children that they're not capable of caring for, that's a reasonable position to hold. But how do we determine who "shouldn't" breed? That's where the eugenic mentality comes in. Given that based on his frequent comments that the state should be extremely generous with welfare benefits, ~tv presumably believes that the government is obliged to subsidize unlimited childbearing among the poor. So by what criteria would he (or anybody) decide that a person, or class of people, shouldn't have children.

More chilling is the attitude contained in his language. People don't "breed"; animals do. The inhumanity inherent in his choice of words tells us a lot.

I'd say that most of us, even all of us, at some time or another have thought that the world would be a better place if only That Sort of Person would quit having children, or would cease to exist. And maybe, from a coldly rational point of view, we would be right. But it's very, very easy to slip from that observation to the conviction that because That Sort of Person doesn't meet our moral or aesthetic criteria, that they are in some sense deserving of being treated as less than fully human -- and even a menace to society.

I once visited the Yad Vashem Holocaust memorial in Jerusalem, and saw in the exhibit how the Holocaust didn't just appear out of nowhere. It began with the idea that the "health" of German society was a paramount social value. And then the eugenicists started their work, discussing how the "unfit" -- mental defectives, the disabled and others -- harmed the overall health of society. And then the Jews and others became identified as "parasites" on the body politic -- that is, an entire class of human beings were likened to animals. Little by little, German society became conditioned to see its own progress toward a state of greater social health depended on ridding itself of classes of people whose failure to meet the overclass's standards rendered them not only less than human, but a danger to the majority. And then came the Final Solution.

Look, I'm not saying that every question having to do with genetics and human life can be reduced to the Holocaust. But surely, given that the greatest stain on humanity's conscience in mankind's history occurred within living memory, and its philosophical roots lay in the idea that there can be human beings whose very existence is immoral -- well, surely all of us are obliged to proceed on this front in fear and trembling, and with extreme caution. If we proceed at all. I have far, far more trust in the wisdom of the Catholic Church and Protestant fundamentalists in this matter than I do in the judgment of scientists and other experts who can only see the future, but never the past.

I'll give the final word to Yuval Levin again:

The challenge of eugenics was, and is again, a challenge to our egalitarianism. That is what lies at the heart of the abortion debate, and of the larger debate about emerging biotechnologies. These arguments are not about when a new human life begins—an empirical matter not in real dispute—but about whether every human life is equal. That question is a perfectly serious one, and there are defensible positions on both sides. But too many American progressives have answered in the negative without thinking through the consequences. And increasingly the reasons they give are not liberal reasons—reasons of liberty and personal choice—but scientific reasons, be it the great promise of some very particular avenue of medical research, or the instrument readings that demonstrate Down’s or another genetic condition.

These progressives are, in this sense, new eugenicists. That doesn’t mean they would abide Nazi medicine or forced sterilizations. But it does mean they abide scientific selection to eliminate the weakest among us.