Some Scientists’ Openness to the Possibility of Genetic Differences in Mental Traits Among Racial and Ethnic Groups

As I said in my first post on the Harvard e-mail controversy, I believe we should be open to the possibility of genetic racial differences in intelligence, just as we should be open to a wide range of other scientific possibilities. I have not simply been arguing that people should have a First Amendment argument to express such openness. I have been arguing that such openness is in fact sound, and that closing off this possibility in our minds (and in our conversations) cannot be sound, especially given how much scientists have yet to learn about the genetic basis of intelligence.

Now, for the reasons I gave in that post and in others, I think this position does not require reliance on authority. If you think that I’m misunderstanding the statements I quote below, or if you think that those statements are not credible, I will happily stand on my original argument.

But in case it’s helpful, I thought I’d pass along some recent statements from scientists who work in this field — statements that I think help highlight the correctness of the view I defend, and its practical importance for the coming years. First, a 2006 item from noted Harvard psychologist Prof. Steven Pinker, who is actually skeptical about claims of racial differences in intelligence:

The year 2005 saw several public appearances of what will I predict will become the dangerous idea of the next decade: that groups of people may differ genetically in their average talents and temperaments.

  • In January, Harvard president Larry Summers caused a firestorm when he cited research showing that women and men have non-identical statistical distributions of cognitive abilities and life priorities.
  • In March, developmental biologist Armand Leroi published an op-ed in the New York Times rebutting the conventional wisdom that race does not exist. (The conventional wisdom is coming to be known as Lewontin’s Fallacy: that because most genes may be found in all human groups, the groups don’t differ at all. But patterns of correlation among genes do differ between groups, and different clusters of correlated genes correspond well to the major races labeled by common sense.)
  • In June, the Times reported a forthcoming study by physicist Greg Cochran, anthropologist Jason Hardy, and population geneticist Henry Harpending proposing that Ashkenazi Jews have been biologically selected for high intelligence, and that their well-documented genetic diseases are a by-product of this evolutionary history.
  • In September, political scientist Charles Murray published an article in Commentary reiterating his argument from The Bell Curve that average racial differences in intelligence are intractable and partly genetic.

Whether or not these hypotheses hold up (the evidence for gender differences is reasonably good, for ethnic and racial differences much less so), they are widely perceived to be dangerous. Summers was subjected to months of vilification, and proponents of ethnic and racial differences in the past have been targets of censorship, violence, and comparisons to Nazis. Large swaths of the intellectual landscape have been reengineered to try to rule these hypotheses out a priori (race does not exist, intelligence does not exist, the mind is a blank slate inscribed by parents)….

Advances in genetics and genomics will soon provide the ability to test hypotheses about group differences rigorously…. [T]he prospect of genetic tests of group differences in psychological traits is both more likely and more incendiary [than the more commonly discussed prospects of cloning and human genetic enhancement], and is one that the current intellectual community is ill-equipped to deal with.

Now let me stress again: Prof. Pinker takes the view that, while “the evidence for gender differences is reasonably good,” “for ethnic and racial differences [it is] much less so.” But he is open to the possibility that there are indeed such differences. He embraces the prospect of “test[ing] hypotheses about group differences rigorously.” He seems to condemn what he sees as the fact that “[l]arge swaths of the intellectual landscape have been reengineered to try to rule these hypotheses out a priori,” with “these hypotheses” clearly including hypotheses about “ethnic and racial differences.” And it seems pretty clear that if he thought that the evidence for ethnic and racial differences was nil, or that such differences were theoretically impossible, he would have said something other than “much less so.” (After all, ruling out ethnic and racial differences, if such ruling out were sound, would defuse one of the main barriers to dealing with the matters he describes, yet would leave his suggestion amply noteworthy and controversial enough for any scholar’s tastes, even if limited to gender differences.)

And of course, if we thought that Pinker wasn’t open to the possibility that there are indeed such differences, I take it that we would and should be quite skeptical of his assertion that the evidence there is “much less” good than the evidence for gender differences. How can you trust an evaluation of contested evidence from a scientist who had approached the evidence with the prejudgment that it absolutely must be wrong? (Maybe we might trust it if he persuasively argued that the claims were theoretically impossible, or so controverted by so many facts that they must be wildly improbable — but the “much less so” statement makes clear that these aren’t his positions.)

Or consider this material from a 2009 Nature article by Profs. Bruce T. Lahn (Univ. of Chicago) and Lanny Ebenstein (UC Santa Barbara), titled Let’s Celebrate Human Genetic Diversity:

[E]nough evidence has come to the fore to warrant the question: what if scientific data ultimately demonstrate that genetically based biological variation exists at non-trivial levels not only among individuals but also among groups? In our view, the scientific community and society at large are ill-prepared for such a possibility. We need a moral response to this question that is robust irrespective of what research uncovers about human diversity….

The current moral position is a sort of ‘biological egalitarianism[,]’ … the view that no or almost no meaningful genetically based biological differences exist among human groups, with thee xception of a few superficial traits such as skin colour…. We believe that this position, although well intentioned, is illogical and even dangerous, as it implies that if significant group diversity were established, discrimination might thereby be justified….

It is also important to recognize that humanity is diverse in its diversity — which is to say that genetic diversity contributes to variation across numerous physical, physiological and cognitive domains. How individuals or groups fare in one domain can be largely independent of how they fare in others. For example, although IQ is a useful metric of some aspects of intelligence and it is partly heritable, it is far from a complete measure of total mental capacity. Therefore, acceptance of human genetic diversity in its totality necessairly leads to the rejection of unidimensional rankings of the capacity of human individuals or groups.

The authors seem open to the possibility that there is substantial “cognitive” “variation” (on average) among groups. Now to be sure, they would counsel again concluding that one group is less intelligent than another on some unitary scale — and that scientific recommendation may prove to be sound. At the same time, they do say that “IQ is a useful metric of some aspects of intelligence”; so it may be that, while comprehensive scientific studies of intelligence need to look at many different measures, more focused applications may usefully rely on IQ alone. In any event, if the authors are right that there is group “diversity … across cognitive domains,” it seems unsound to rule out the possibility that one particular group may on average be less genetically predisposed to intelligence, at least under some “useful metric,” than some other group.

Other scientists say related things. University of Virginia psychology professor Jonathan Heidt asserts that “Recent ‘sweeps’ of the genome across human populations show that hundreds of genes have been changing during the last 5-10 millennia in response to local selection pressures,” and that “traits that led to Darwinian success in one of the many new niches and occupations of Holocene life — traits such as collectivism, clannishness, aggressiveness, docility, or the ability to delay gratification” may therefore prove to be ethnically linked (to a degree, of course) on a genetic level. (By the way, as I said in my first post on this matter, I would no more rule out the possibility that Jews, my own ethnic group, are genetically predisposed to more acquisitiveness than average than that some ethnic groups are genetically predisposed to less intelligence than average — though of course I would not accept either conclusion as true without solid evidence. You can’t rule out scientific possibilities just because some evil people had, for unscientific reasons, asserted similar things in the past.)

“I believe that the ‘Bell Curve’ wars of the 1990s, over race differences in intelligence,” Heidt continues, “will seem genteel and short-lived compared to the coming arguments over ethnic differences in [these sorts of] traits…. [W]hatever consensus we ultimately reach, the ways in which we now think about genes, groups, evolution and ethnicity will be radically changed by the unstoppable progress of the human genome project.”

Likewise, here’s an excerpt from an article by University of New Mexico psychology professor Geoffrey Miller in The Economist, Nov. 13, 2009:

[Coming developments in] genetics will reveal much less than hoped about how to cure disease, and much more than feared about human evolution and inequality, including genetic differences between classes, ethnicities and races….

In 2010, … [d]ozens of papers will report specific genes associated with almost every imaginable trait—intelligence, personality, religiosity, sexuality, longevity, economic risk-taking, consumer preferences, leisure interests and political attitudes. The data are already collected, with DNA samples from large populations already measured for these traits….

When sequencing costs drop within a few years below $1,000 per genome, researchers in Europe, China and India will start huge projects with vast sample sizes, sophisticated bioinformatics, diverse trait measures and detailed family structures. (American bioscience will prove too politically squeamish to fund such studies.) …

We will … identify the many genes that create physical and mental differences across populations, and we will be able to estimate when those genes arose. Some of those differences probably occurred very recently, within recorded history. Gregory Cochran and Henry Harpending argued in “The 10,000 Year Explosion” that some human groups experienced a vastly accelerated rate of evolutionary change within the past few thousand years, benefiting from the new genetic diversity created within far larger populations, and in response to the new survival, social and reproductive challenges of agriculture, cities, divisions of labour and social classes. Others did not experience these changes until the past few hundred years when they were subject to contact, colonisation and, all too often, extermination.

If the shift … to sequencing studies finds evidence of such politically awkward and morally perplexing facts, we can expect the usual range of ideological reactions, including nationalistic retro-racism from conservatives and outraged denial from blank-slate liberals. The few who really understand the genetics will gain a more enlightened, live-and-let-live recognition of the biodiversity within our extraordinary species — including a clearer view of likely comparative advantages between the world’s different economies.

Now these are serious scientists. I have no reason to think they’re fools or racists. And they seem to be open to the possibility of genetic differences among racial and ethnic groups in mental processes related to intelligence, temperament, and the like. Some may be skeptical about those differences. Some may expect that the differences are going to be mixed with other countervailing differences. But they are unwilling to rule out the possibility that there are such differences, and they seem to think that it’s important that we as a society be prepared to discuss those differences.

Of course, these scientists may be wrong. There are doubtless other scientists who disagree with them. The history of science is filled with highly credentialed and respected scientists who have proven to be wrong.

But the question right now isn’t whether there are the genetic differences among groups that these scientists suggest might (or might not) exist. It’s whether we, both scientists and interested laypeople, should be open to the possibility that they exist, and whether those of us who admit — in an e-mail to a close friend — that such openness should be publicly pilloried for daring to think that this is indeed a possibility. The answer, it seems to me, is that we should indeed be open to this scientific possibility, as the scientists whom I quote above are open to it, and that we should not be condemned for this openness.

And, if these scientists are correct in their prediction about the coming debate, then this is not just an ethical position, but a pragmatically important one. The people I quote are saying that more data on this subject is coming, and that our society needs to be ready to seriously confront both the factual evidence and the possible ethical implications of this evidence, whatever conclusion the factual evidence ultimately leads to.

Which sort of “intellectual community” is most likely to become less “ill-equipped to deal with” these issues: An intellectual community in which people know that they may be publicly pilloried by their university departments for expressing to a friend in a private e-mail that they are open to the possibility of racial differences in intelligence (and in particular that they are open to the possibility that the observed black-white IQ gap is partly explained by genetics)? Or an intellectual community in which openness to this scientific hypothesis, as to other scientific hypotheses, is seen as a proper aspect of a scientific approach to a question of scientific fact?