Thursday, May 21, 2009

Nisbett answered by Rushton & Jensen


When the first publicity for Nisbett's recent book on IQ came out, I said: "I have not read the book and nothing in the review encourages me to do so but I assume that some of my colleagues who specialize in IQ studies will read it and dissect it in due course. Meanwhile, I just offer a few comments that occur to me".

My expectation has now been fulfilled. I have just received from J.P. Rushton the draft of a paper which dissects Nisbett's arguments in detail. It is in the form of a book review so should see academic publication fairly soon.

As I also expected, the liberties taken with the facts by Nisbett are enormous. If there is only one finding out of 5 that suits Nisbett, he will quote that one finding and ignore the other 4. That is a caricature of how real science is done.

Many of the points that Rushton & Jensen make are similar to points I have made in my various comments on Nisbett (See here, here and here) but Rushton & Jensen give the actual figures complete with full references.

As the paper is in draft, I cannot quote any of it directly but I can quote an excerpt that they provide from Flynn. Flynn has been one of the chief proponents of environmental rather than genetic influences on IQ and Nisbett relies on him heavily for some of his arguments. Flynn does however listen to those on the genetic side of the debate and he has recently changed his tune considerably. The following is from page 85 of Flynn's 2008 book.
There are two messages. The first is familiar: You cannot dismiss black gains on whites just because they do not tally with the g loadings of subtests. But the second is new and unexpected. The brute fact that black gains on whites do not tally with g loadings tells us something about causes. The causes of the black gains are like hearing aids. They do cut the cognitive gap but they are not eliminating the root causes. And conversely, if the root causes are somehow eliminated, we can be confident that the IQ gap and the g gap will both disappear".

In other words, Flynn accepts that there is an underlying black/white difference in IQ that cannot be traced to environmental factors. Nisbett quotes a lot from Flynn but he does NOT quote that conclusion.

And Rushton & Jensen also report empirical tests of the arm-waving assertions that emanate from Leftists about black environmental disadvantage. None of the assertions are in fact borne out by the research findings.

In that connection I found out about a quite remarkable fact that I was not previously aware of. What if a little kid came from such a poor environment that he had to be hospitalized for malnutrition and was then adopted out into a white family? One would think that a kid from such a background would be permanently handicapped. They obviously would not come from an elite family to start with and nutrition during infancy is known to be very important to subsequent development. Yet precisely that experience has happened to considerable numbers of children from East Asian backgrounds (Korea etc.). I think you know what I am going to say: Far from being dumb, these kids were after only a few years scoring ABOVE the white average on IQ! Genetics triumph! East Asians are of course in general smarter than we Anglos. Their weakness is that they respect authority too much.

Leftists will of course argue that the finding simply show what a wonderful job white adoptive parents do but isn't it odd that blacks adopted by whites still stay close to THEIR average racial IQ -- i.e. around a whole standard deviation below whites -- particularly if we look at adult IQ rather than IQ measured during childhood. It is an old truth that efforts to raise black IQ sometimes seem to be doing some good during childhood but by adulthood the improvement vanishes. Needless to say, Nisbett quotes adoption studies where IQ was measured in childhood and ignores major studies where IQ was measured in adulthood.

In most fields of science, work as incompetent as Nisbett's would earn him nothing but scorn from his colleagues but Nisbett is already heavily laden with honours and will no doubt receive even more honours before long. The human race loves its myths far more than it loves facts.

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