Last Round on Race, IQ, Saletan, Etc.

I figured Julian Sanchez would have an interesting point to make about all this, and sure enough, he does:

A friend once told me about a study—perhaps a commenter can find me a reference?—in which two groups of students were casually informed in advance that previous studies had shown that women tend to perform less well on such tests. As I (fuzzily) recall, this happened to be true, and was true for the control group in the test. But the women in the group who'd been informed of this performed much worse, greatly magnifying the gender gap. Which is to say, if I'm getting the details right, that dwelling on certain kinds of differences—whatever their source—comes with its own costs.

One such study (pilfered from Julian's comments thread), is here. It's a phenomenon very similar to the bandwagon effect in polling, and underscores just how difficult it is to prise apart the various factors determining IQ scores according to their aetiologies. So then, why not, as a number of folks have suggested, including commenters here at Jewcy, just say, the IQ gap could be environmental or could be a combination of genetic and environmental factors, we just don't know, and leave it at that?

First, let's consider the epistemic situation we're in. We already know that there are environmental factors that have a role in determining how individuals do on IQ tests --- no one disputes that. What we have, as far as evidence of race-linked genetic differences goes, is the simple prima facie evidence that there is an IQ gap, and despite a lot of furious (and fraudulent) obfuscation, not a jot of, shall we say, secunda facie evidence. Taking the epistemic position that it could be environmental, it could be environmental and genetic, we just don't know, is not really much more justified than the epistemic position that it could be environmental, it could be (earthly) environmental and also caused by perturbations in tbe orbit of Saturn, we just don't know. In fact, it wouldn't be terribly difficult to come up with prima facie evidence that some utterly contrived, gruesome, and gerrymandered phenomenon is tied to differential performance on IQ tests --- just specify some disjunction of events that occurs only when and where black people take IQ tests, e.g. the Brownian motion of particles not contiguous with but in the immediate spatiotemporal vicinity of black test-takers, observe the correlation between the data sets, and posit a causal relationship. But of course, my contrived example doesn't survive a moment's scrutiny, and likewise, the hereditarians' evidence doesn't survive more than a few moments' scrutiny.

Second, we should be careful to distinguish two claims: (1) Genes have something to do with determining mature cognitive abilities. (2) Race is a reliable predictor of average intelligence. (1) is undeniable (and I've been a little dismayed to see some people assuming that I deny it). No two people are equal in their cognitive abilities, and of course genes are part of the causal history of those inequalities. But what the evidence resoundingly fails to warrant is a jump from (1) to (2) --- there is no secunda facie or deeper evidence that inequalities in cognitive abilities have anything to do with race. When spelled out in explicit terms, the empirical weakness of the hereditarian position can't be concealed, but because (1) and (2) are superficially similar --- because, in short, our commonplace notions of race cross-cut popular understandings of genetics --- a sufficiently clever rhetorician can move from (1) to (2) and make the move appear innocuous. John Holbo has a name and analysis of the general rhetorical strategy:

I call it ‘the two-step of terrific triviality’. Say something that is ambiguous between something so strong it is absurd and so weak that it would be absurd even to mention it. When attacked, hop from foot to foot as necessary, keeping a serious expression on your face. With luck, you will be able to generate the mistaken impression that you haven’t been knocked flat, by rights. As a result, the thing that you said which was absurdly strong will appear to have some obscure grain of truth in it. Even though you have provided no reason to think so.

And that, folks, is basically what we're dealing with. Because we can't, and shouldn't jettison our belief that people in general possess unequal cognitive abilities, and that genomic differences are part of the story, some people are unwilling to let go completely of the idea that the differentials in average IQ scores exist in part in virtue of the ethnic identities of the test-takers, an entirely different claim. No matter how many times one points out that the hereditarians' evidence doesn't support their claims, the argument just will not give up the ghost.

There's one final point that I ought to have made sooner and really ought to make now. Namely: Race is an extraordinarily confused, ill-defined, and scientifically useless concept. For the purposes of my articles I abided by the naming conventions Saletan was employing, but it's really time to set the record straight. The average genomic difference between two individuals attributable to what we would commonly think of as a racial difference is vanishingly small, far, far less, for exmple, than the genomic difference between men and women (who nevertheless have the same average IQ). Moreover, since, as Robert Farley puts it, "up until about 200 years ago, the vast vast vast vast vast vast vast vast majority of people in Africa, Asia, South America, North America, and Europe lived in essentially similar economic conditions," meaning that it's preposterous even in prima facie terms to suggest that homo sapiens broke apart into distinct subspecies due to divergent evolutionary pressures that have existed for just 200 years.

And last of all, Cosma Shalizi makes a point about peer review and its limitations that reinforces my own, and is particularly pertinent to the commenter who populated a now several-pages-long comment thread with links to the collected works of J. Phillipe Rushton:

A journal's peer review is only as good as the peers it uses as reviewers. If everyone, or almost everyone, who referees for some journal is in the grip of the same mistake, then they will not catch it in papers they review, and the journal will propagate it. In fact, since journals usually recruit new referees from their published authors or people recommended by old referees, mistakes and delusions can become endemic and self-confirming in epistemic communities associated with particular journals. To give a concrete example, the community using Physica A is pretty uniformly (and demonstrably) mistaken about how to tell when something is a power-law distribution, so what that journal publishes about power laws is unreliable, and those who derive their training and information from that journal go on to propagate the errors. It would be easy to find even more extreme examples from the physical and mathematical sciences (especially, I must say, among journals published by Elsevier), but it would take too long to explain why they are wrong.  

Now then, unless some glossy mag wants to pay for a feature piece on this stuff, this is the last you'll hear of it from me.