Graham, who made his fortune by inventing shatterproof eyeglasses, feared mankind was in danger because natural selection had stopped working on human beings. He explained his views in a muscular 1971 book, The Future of Man. Over millenniums, nature's brutality had strengthened the human gene pool, allowing the strong and smart to reproduce, while killing the weak before they could. But once man mastered his natural environment, Graham argued, he jumped the evolutionary track. Better living conditions allowed "retrograde humans" to reproduce. In modern America, thanks to cradle-to-grave social welfare programs, these incompetents and imbeciles were swamping the intelligent. This dysgenic crisis would surely bring communism and the regression of mankind. All that could save us, Graham warned, was "intelligent selection": Our best specimens must have more children. [...]As a modern reflection on the American eugenics movement, this passage is pretty typical. Eugenicists are described as contaminated by their association with Hitler, and perhaps - as happens elsewhere in the Slate series - their tactics are mocked. It's easy to get the impression that the eugenic movement had worthwhile aims, if only the lamentable tendency to genocide could be avoided. Rarely do modern discussions of eugenics point out that the most basic assumption of the movement was flawed: the "dysgenic crisis." It didn't exist then. It doesn't exist now.
But by the time Graham opened the repository, eugenics had been utterly tarnished by Nazism. It was considered at best elitist, at worst racist and genocidal.
In 1951, C.M. Kornbluth wrote a dysgenic-crisis story called "The Marching Morons," in which generations of underbreeding by intellectual and cultural elites, combined with overbreeding by the poor, uneducated, unsuccessful masses, have led to a world in which the average person is an illiterate moron, incapable of contributing to the upkeep of society. In reality, over successive generations IQs are rising worldwide. Every revision of IQ tests makes them harder, so that the average score will continue to be 100 rather than creeping up to 105, 110, 115.
Moreover, the percentage of Americans who are diagnosed with mental retardation - defined as an IQ below 70 plus substantial difficulties performing necessary skills of daily life - has remained steady for a full century. Hundreds of thousands of "mentally defective" individuals were sterilized under eugenics laws in the first half of this century, yet that practice didn't even cause a blip in the prevalence of mental retardation among children. Nor did the repeal of involuntary sterilization laws cause an increase in mental retardation rates. There is simply no evidence that low IQs or low levels of functional intelligence are increasing in the general population, "dysgenic" breeding habits or not.
The rise of genetic testing and counseling, plus the availability of legal abortion, has led to declining rates of genetic forms of mental retardation such as Downs Syndrome. One relatively common type of mental retardation, PKU, can now be diagnosed at birth and prevented by a strict diet avoiding phenylalanine. Iodized salt, of all things, has reduced the rate of cretinism, a form of mental retardation caused by iodine deficiency. But these types of mental retardation aren't usually what eugenicists are worried about. They're relatively uncommon, and they tend to be severe and disabling enough that persons affected by them rarely reproduce.
Eugenicists worry much, much more about people who are normal in most respects, but aren't very bright. The vast majority of people with mental retardation have mild forms which don't necessarily prevent them from, for example, living outside institutions and being attractive to the opposite sex. They're the ones who were sterilized in large numbers in the 20s and 30s, and they're the ones who were supposedly going to provide us with our future "Marching Morons." Except that they don't. If two people clinically diagnosed as "mentally retarded" marry and have children, 72% of their children will not be mentally retarded. IQ is only partially heritable, and there tends to be regression toward the mean.
It concerns me that people may come away from the Slate series, and other modern discussions of eugenics, with the impression that eugenicists correctly identified a problem to which the solution was morally unacceptable. In fact, the eugenicists incorrectly identified a problem, to which they proposed morally unacceptable solutions. The difference is considerable.