One final point on the Africa paragraphs. When I said I “read” the book, I read it in the way I read text books—going a bit out of order, carefully reading main arguments, and skimming parts that seemed unimportant. I’ve spent enough time in the book to have read every single page, but I didn’t go through it in the chronological page-by-page way I’d read a Jack Reacher novel.
If you are taking what the book actually says at face value, then the paragraphs about Africa have nothing to do with the main point of the book. Nothing. On the other hand, if you are acting like a prosecuting attorney who is claiming that the book has an insidious purpose that is other than what it claims to be, of course you are going to focus on those paragraphs and claim that they
are the entire point.
Here is what Murray says about the reaction to those three paragraphs about Africa in the Afterward:
The topic of African IQ is a tiny piece of The Bell Curve— three paragraphs on pp. 288– 289 intended to address a hypothesis Herrnstein and I heard frequently: The test scores of American blacks have been depressed by the experience of slavery and African blacks will be found to do better. We briefly summarize the literature indicating that African blacks in fact have lower test scores than American blacks.
Lane and Kamin assault this conclusion ferociously. We are an easy target. We say so little about African IQ that it is easy for Lane and Kamin to point to the many technical difficulties of knowing exactly what is going on. But we also omit many more details that make a strong case that African blacks have very low scores on standardized mental tests. Lane and Kamin want our sources to be weak and racist. That they are not bears importantly, if inconclusively, on possible genetic racial differences.
Blinded to that possibility by their seeming prejudgment of the issue, Lane and Kamin apparently are not worried about what will happen when their critiques lead other scholars to explore the studies that we cited. They should be. Even when samples of Africans are selected in ways that will tend to bias the results upward— for example, by limiting the sample to people who have completed primary school (many of the least able have dropped out by that time), people who are employed, or people who live in urban areas— and even when the tests involved are ones such as the Ravens Standard Progressive Matrices (SPM), designed for cross-cultural comparisons, devoid of any requirements of literacy or numeracy, the scores of African samples everywhere have been in the region of two standard deviations below European or East Asian means. The studies vary in quality, but some are excellent, and it is not the case that the better the study is, the higher the African score is found to be. On the contrary, some of the lowest scores have been found in the largest, most careful, and most recent studies.
To illustrate how troubling the results have been, let me turn to two studies postdating Richard Lynn’s review that we cite on p. 289. One was a South African study led by Kenneth Owen published in the refereed British journal Personality and Individual Differences. 17 Its sample consisted of enrolled seventh-grade students: 1,056 whites, 778 coloureds (mixed race), 1,063 Indians, and 1,093 blacks. The SPM was administered without time limits. Except for the Indians, subjects were tested by school psychologists of the same ethnic group. Owen presents the full psychometric profile for the test results (distributional characteristics, reliability, item difficulty, item discrimination, congruence coefficients, and discriminant analysis), demonstrating that the test was measuring the same thing for the various ethnic groups. The differences in test means, expressed in standard deviations, were as follows: Indian-white: −. 52; coloured-white: − 1.35; black-white: − 2.78. The second example of a recent, careful study was conducted by a black scholar, Fred Zindi, and published in the Psychologist. 18 It matched 204 black Zimbabwean pupils and 202 white English students from London inner-city schools for age (12— 14 years old), sex, and educational level, both samples being characterized as “working class.” Despite the fact that the white sample was well below average for the whites, with a mean IQ measured by the Wechsler Intelligence Scale for Children-Revised (WISC-R) of only 95, the black-white difference was 1.97 standard deviations on the SPM and 2.36 standard deviations on the WISC-R. Professor Zindi expressed the SPM results as IQ scores. The means for the Zimbabwean sample were 72 for the SPM and 67 for the WISC-R, consistent with Richard Lynn’s estimates. There is reason to think that the WISC-R score was somewhat depressed by language considerations but not much: The (nonverbal) performance IQ score of the Zimbabwean sample was only 70. What should one make of these results?
Above all, one must proceed cautiously in drawing conclusions, for all the reasons that kept us from presenting these results in detail in The Bell Curve. The problem is not, as often alleged, that such studies are written by racists (in the two instances just cited, a charge belied by Owen’s scholarly reputation and by Zindi’s race) but that the African story is still so incomplete. Our view was that the current differences will narrow over time, probably dramatically, as nutrition and the quality of schools for black Africans improve. Changes in black African culture may provide an environment more conducive to cognitive development among young children. But the current differences as measured through these samples as of the 1990s are not figments of anyone’s imagination. Lane, Kamin, and others who have attempted to discredit The Bell Curve by focusing on our “tainted sources” have ensured that the African data will get more attention.
Herrnstein, Richard J.; Murray, Charles. Bell Curve: Intelligence and Class Structure in American Life (A Free Press Paperbacks Book) (p. 565-566). Free Press. Kindle Edition.