Why write about this topic? Why hurt people's feelings? Why gratify bigots?
Because truth matters. Because the truth isn't as bad as our ignorant, half-formed fears and suspicions about it. And because you can't solve a problem till you understand it.
Two days ago, I said we could fight the evidence of racial differences in IQ, or we could accept it. Yesterday, I outlined the difficulty of fighting it. What happens if we accept it? Can we still believe in equality?
Let's look past our fears and caricatures and see what the evidence actually teaches us.
1. Individual IQ can't be predicted from race. According to the data, at least 15 percent to 20 percent of black Americans exceed the average IQ of white Americans. If you think it's safe to guess that a white job applicant is smarter than a black one, consider this: The most important job in the world is president of the United States. Over the last seven years, the most important judgment relevant to that job was whether to authorize, endorse, or oppose the use of force in Iraq. Among the dozen viable candidates who have applied for the job, one is black. Guess which one got it right?
2. Subgroup IQ can't be predicted from race. Go back and look at the German study I mentioned yesterday. Kids fathered by black soldiers scored the same as kids fathered by white soldiers. The explanation offered by hereditarians was that blacks in the military were screened for IQ, thereby wiping out the racial IQ gap.
Think about that explanation. It undermines the claim, attributed to James Watson by the Times of London, that "people who have to deal with black employees" find equality untrue. (The Times purports to have Watson's interview on tape but hasn't published the whole quote or responded to requests for it.) If employment screens out lower IQs, you can't infer squat about black employees. And that isn't the only confounding factor. Every time a study highlights some group of blacks who score well, hereditarians argue that the sample isn't random. That may be true, but it's also true of the people you live next to, work with, and meet on the street. Every black person in your office could have an IQ over 120.
3. Whitey does not come out on top. If you came here looking for material for your Aryan supremacy Web site, sorry. Stratifying the world by racial IQ will leave your volk in the dust. You might want to think about marrying a nice Jewish girl from Hong Kong. Or maybe reconsider that whole stratification idea.
4. Racism is elitism minus information. No matter how crude race is as a proxy for intelligence, some people will use it that way, simply because they can see your skin but not your brain. What if we cut out the middleman? What if, instead of keeping individual IQs secret, we made them more transparent? If you don't accept IQ, pick some other measure of intelligence. You may hate labeling or "tracking" kids by test scores, but it's better than covering up what's inside their heads and leaving them to be judged, ignorantly, by what's on the surface.
5. Intermarriage is closing the gap. To the extent that IQ differences are genetic, the surest way to eliminate them is to reunite the human genome. This is already happening, including in my own family. In 1970, 1 percent of U.S. marriages were between blacks and nonblacks. By 1990, it was 4.5 percent. It may be the best punch line of the IQ debate: The more genetic the racial gap is, the faster we can obliterate it.
6. Environment matters. Genetic and environmental theories aren't mutually exclusive. Hereditarians admit that by their own reading of the data, nongenetic factors account for 20 percent to 50 percent of IQ variation. They think malnutrition, disease, and educational deprivation account for a big portion of the 30-point IQ gap between whites and black Africans. They think alleviation of these factors in the United States has helped us halve the deficit. Transracial adoption studies validate this. Korean adoption studies suggest a malnutrition effect of perhaps 10 IQ points. And everyone agrees that the black-white IQ gap closed significantly during the 20th century, which can't have been due to genes.
7. IQ is like wealth. Many people who used to condemn differences in wealth have learned to accept them. Instead of demanding parity, they focus on elevating everyone to an acceptable standard of living. Why not treat IQ the same way? This seems particularly reasonable if we accept IQ in the role for which science has certified it: not as a measure of human worth, but as a predictor of modern social and economic success.
As it turns out, raising the lowest IQs is a lot easier than equalizing higher IQs, because you can do it through nutrition, medicine, and basic schooling. As these factors improve, IQs have risen. If racial differences persist, is that really so awful? Conversely, if we can raise the lowest IQs, isn't that enough to justify the effort? One of the strangest passages in IQ scholarship is a recent attempt by hereditarians to minimize their own mediated-learning study because, while it "did raise the IQ of the African students from 83 to 97, this is still low for students at a leading university." You've got to be kidding. Screw the other universities. Going from 83 to 97 is a screaming success.
8. Life is more than g. Every time black scores improve on a test, hereditarians complain that the improvement is on "subject-specific knowledge," not on g (general intelligence). But the more you read about progress in things other than g, the more you wonder: Does g expose the limits of the progress? Or does the progress expose the limits of g?
If the progress were on g, the test-takers' lives would be easier, since g helps you apply what you've learned to new contexts. But that doesn't make other kinds of progress meaningless. People with low IQs can learn subject by subject. And they may have compensating advantages. One of my favorite disputes in the IQ literature is about test scores in Africa. Environmentalists argued that African kids lacked motivation. Hereditarians replied that according to their own observations, African kids stayed longer to check their answers than white kids did. Diligence, too, is a transferable asset.
9. Children are more than an investment. All the evidence on race and IQ says black kids do better at younger ages, particularly with help from intervention programs. Later, the benefits fade. Hereditarians say this is genetics taking over, as happens with IQ generally. Suppose that's true. We don't abandon kids who are statistically likely to get fatal genetic diseases in their teens or 20s. Why write off kids whose IQ gains may not last? The economics may not pay off, but what about human rights?
10. Genes can be changed. Hereditarians point to phenylketunuria as an example of a genetic but treatable cognitive defect. Change the baby's diet, and you protect its brain. They also tout breast-feeding as an environmental intervention. White women are three times more likely than black women to breast-feed their babies, they observe, so if more black women did it, IQs might go up. But now it turns out that breast-feeding, too, is a genetically regulated factor. As my colleague Emily Bazelon explains, a new study shows that while most babies gain an average of seven IQ points from breast-feeding, some babies gain nothing from it and end up at a four-point disadvantage because they lack a crucial gene.
The study's authors claim it "shows that genes may workvia the environment to shape the IQ, helping to close the natureversus nurture debate." That's true if you have the gene. But if you don't, nurture can't help you. And guess what? According to the International Hapmap Project, 2.2 percent of the project's Chinese-Japanese population samples, 5 percent of its European-American samples, and 10 percent of its Nigerian samples lack the gene. The Africans are twice as likely as the Americans, and four times as likely as the Asians, to start life with a four-point IQ deficit out of sheer genetic misfortune.
Don't tell me those Nigerian babies aren't cognitively disadvantaged. Don't tell me it isn't genetic. Don't tell me it's God's will. And in the age of genetic modification, don't tell me we can't do anything about it.
No, we are not created equal. But we are endowed by our Creator with the ideal of equality, and the intelligence to finish the job.
Will Saletan covers science, technology, and politics for Slate and says a lot of things that get him in trouble.