



What if Charles Murray is right? What if some of the various racial gaps in cognitive performance are due to genetics? Would that be the end of the world?

It is considered appropriate to hyperventilate as if you believe so.

On the other hand, what if Murray is wrong and his best critic, James Flynn, is right? Would that validate traditional liberal approaches to bridging The Gap?

Vox recently ran a long article by three professors entitled “Charles Murray is once again peddling junk science about race and IQ.” It was full of bluster about how “There is currently no reason at all to think that any significant portion of the IQ differences among socially defined racial groups is genetic in origin.”

But if you read the long article closely, you”d have discovered that what it was really about was how Murray is right and the conventional wisdom is wrong on (at least) 80 percent of the scientific issues:

(1) Intelligence, as measured by IQ tests, is a meaningful construct that describes differences in cognitive ability among humans.

(2) Individual differences in intelligence are moderately heritable.

(3) Racial groups differ in their mean scores on IQ tests.

(4) Discoveries about genetic ancestry have validated commonly used racial groupings.

The three scientists admitted, in so many words, that they only disagreed with:

5) On the basis of points 1 through 4, it is natural to assume that the reasons for racial differences in IQ scores are themselves at least partly genetic.

The authors were clearly disturbed by the widespread assumption in media and academic circles that, as Vox might say, Charles Murray is “peddling junk science.” YET they agree with Murray about what the science says more than they agree with the Science Denialist orthodoxy. In their minds, the violent bigotry on campus against Murray is occluding awareness of reality and threatening the practice of science in what used to be called the free world.

I”m not going to get into the arguments over (5) here.

After all, we”ll know soon enough from advances in genomic research.

“The scientific answer is coming. So we ought to try to think through the implications of either result.”

James D. Watson, the codiscoverer of the structure of DNA, ended his 2007 memoir Avoid Boring People with an anecdote about the acting president of Harvard, Derek Bok (who had stepped in for Lawrence Summers after Larry had come a cropper for being inappropriately well-informed about the difference in the variance of male and female bell curves), asking Watson worriedly about how soon until the scientific results are in on the genetic basis of IQ:

So I was not surprised when Derek asked apprehensively how many years would pass before the key genes affecting differences in human intelligence would be found. My back-of-the-envelope answer of “fifteen years” meant Summers” then-undetermined successor would not necessarily need to handle this very hot potato.

Or it might take, say, twice as long to figure out the causes of “differences in intelligence.” The subject is very complicated.

In any case, the scientific answer is coming. So we ought to try to think through the implications of either result.

(Of course, it will no doubt take decades after that for the upcoming scientific results to penetrate the smug shell of the conventional wisdom. Notice by way of analogy how the eye-rollingly stupid dogma that “race does not exist” has been spreading in this century even as high-tech genome analysis confirms what’s in front of our noses.)

In this essay, though, I want to consider the implication of what few seem to take seriously: What if the Arthur Jensen”Charles Murray line of speculation is wrong, and their finest scientific critic, James Flynn, turns out to be right that white-black differences in cognitive performance turn out to be due to what we might call a cultural cascade?

Jensen, a Berkeley psychologist, argued from 1969 onward that welfare programs were unlikely to close the white-black IQ gap because the socioeconomic status gap between whites and blacks, while considerable, is hardly large enough to account for the IQ difference.

Looking for a way to undermine this logic in the 1970s, Flynn, an American-born political philosopher in New Zealand, dug into the IQ data and noticed something he (and everybody else) hadn”t expected: that raw scores on IQ tests had tended to drift upward by 2 or 3 points per decade all around the world, requiring grading of the tests to be made tougher with each new edition.

There had long been intense debate over whether IQ tests can be comparable across space, but few academics had ever worried that they might be subject to significant changes over time.

Flynn wrote to Jensen to point this out. Jensen responded with four challenges to Flynn to demonstrate that this phenomenon of his was significant. Flynn dug further into the data and was able to largely meet them.

The two battling scholars became admirers of each other as they continued to debate the implications of Flynn’s findings over several decades. In The Bell Curve in 1994, Murray and Richard Herrnstein named Flynn’s discovery the Flynn Effect.

Flynn had hoped that his Effect would offer evidence that the white-black gap was not hereditary. After all, if raw IQ scores on tests were going up 2 or 3 points per decade, that couldn”t be genetic evolution. Some kind of nurture must be driving the change.

But after several decades of research, the Flynn Effect remains somewhat mysterious.

Not all that much has subsequently emerged from research into the Flynn Effect that appears specifically relevant to the race gap. On the other hand, the existence of the Flynn Effect should remind us that we don”t fully understand how the mind works and that the future can bring surprises.

My guess is that the Flynn Effect is related in part to an extended version of Moore’s Law. Even before the silicon chip was invented, information technology had been progressing rapidly since Gutenberg in the 1450s. The pioneers of IQ testing, such as Lewis Terman, designer of the Stanford-Binet test of a century ago, turned out to be strikingly correct about the most important skills of the future, such as processing data. I don”t think it’s a coincidence that Lewis” son, Fred Terman, long Stanford’s dean of engineering, has perhaps the best claim to be the Father of Silicon Valley.

In 2001, Flynn, working with economist William Dickens of the Brookings Institution, put forward a model of how minor genetic differences could lead to sizable differences in nurture. Unfortunately, Flynn chose to illustrate his theory using an example about basketball ability, a sport in which genetic differences are exceedingly obvious:

Take those born with genes that make them a bit taller and quicker than average. When they start school, they are likely to be a bit better at basketball. The advantage may be modest but then reciprocal causation between the talent advantage and environment kicks in. Because you are better at basketball, you are likely to enjoy it more and play it more than someone who is bit slow or short or overweight. That makes you better still…. You are more likely to be picked for your school team and to get professional coaching. Thanks to genes capitalizing on the powerful multiplying effects of the feedback between talent and environment, a modest genetic advantage has turned into a huge performance advantage.

I advised Flynn to change his example to soccer ability, but he stuck with basketball, despite its huge racial disparities, which I think hurt his model’s chance of catching on.