Scholars Refute Kanazawa’s Theory of Intelligence and Health – May 1 2007

May 1st, 2007 Print Print Email Email

In several papers published in the current issue of the British Journal of Health Psychology, scholars from the US and the UK refuted the controversial study of Satoshi Kanazawa that attempted to link health to intelligence. (more…)

In several papers published in the current issue of the British Journal of Health Psychology, scholars from the US and the UK refuted the controversial study of Satoshi Kanazawa that attempted to link health to intelligence.
It may be recalled that Kanazawa’s paper, which was published in the November 2006 issue of the same journal, had trigged a universal uproar, especially for its use of questionable and dubious data about national IQs, including those of Ethiopia and many other African countries, to draw far-reaching conclusions concerning the relationship between intelligence and health.

Among the papers that appeared in the May 2007 issue of the journal is an article by Professors Demissie Alemayehu of Columbia University and Tilahun Sineshaw of Ramapo College of New Jersey, who argued, using extensive citations from evolutionary psychology and inferential statistics, that Kanazawa’s research was “bereft of the rigour” required to address the problem under consideration.

Maintaining that “…. critical elements of his [Kanazawa's] study violate fundamental principles of research methodology…,” Alemayehu and Sineshaw wrote:

“… the validity and robustness of the conclusions of the paper are compromised by fundamental problems, including failure to present competing views with fair balance, use of samples of convenience to draw conclusions about populations, performing tests of significance when there is no theoretical basis to do so and confusing association with causation.”

[British Journal of Health Psychology, Volume 12, Number 2, May 2007, pp. 185-190(6)]

With reference to the dubious nature of Kanazawa’s data, the two scholars pointed out:

“[T]he source of most of Kanazawa’s “macro-level” data is questionable at the best, and misleading at the worst. … A case in point is the national IQ figure used for Ethiopia which was based on a group of 14-15 year-olds who took the Progressive Matrices Standard (PMS) test one year after they had emigrated to Israel (Kaniel and Fisherman, 1991). Even if one accepts the idea that the PMS test measures what has been dubbed general intelligence, the Ethiopian data set, which Kanazawa claimed had been ‘directly measured,’ cannot be taken as a direct measure of the IQ of Ethiopians. The group of adolescents used in the study came from an isolated and desolate region of the country that had experienced a devastating war and famine at the time, not to mention the trauma of moving to a completely new urban environment and the experience of blatant racism once in Israel (Wagaw, 1993). As Kaniel and Fisherman (1991, p. 26) also acknowledged in their original article, ‘[I]n Ethiopia, Jews generally lived in small villages of 50-60 families, remote from urban centers. …. prior to their exodus [to Israel], most had never seen electricity, a telephone, or any technological instruments…. In Israel, they must adjust to climatic differences, life in urban centers, a new language,….’ By any measure, data from a disadvantaged group of people, who had emigrated from a specific region of a country with the attendant social and physical deprivations, cannot be considered representative of a country of over 70 million people with complex historical, ethnic, linguistic, and socio-economic diversity.”

They further noted:

“…. Kanazawa’s knowledge of the socio-historical circumstances under which the Ethiopian data were produced leaves much to be desired. The historical and sociological situatedness of empirical data and how much this contributes to or limits the accuracy of analyses and interpretations that follow have been well established (Cole, 1996). The fallacy of how the Ethiopian national IQ score was constructed certainly casts doubt on the credibility of the entire data and analysis and, by extension, the conclusions of the paper. Ironically, the data obtained from the Bete Israel, as the Ethiopian Jews like to call themselves, should have yielded, according to Kanazawa’s hereditarian view, an average IQ score closer to the Israel national score, since they are believed to be descendants of one of the lost tribes! “

Understandably, Kanazawa’s paper had generated a lot of discussion, both in the print media and in popular online forums. Among the media that gave the discredited theory much publicity was the UK-based paper, “The Observer,” which in its November 5, 2006 issue headlined, “Low IQs are Africa’s curse, says lecturer.” It would be interesting to see if those same news outlets would now give their readers the benefit of exposure to the opposing views expressed in the current issue of the journal.

Interested readers may get copies of the papers, including the aforementioned study by Demissie Alemayehu and Tilahun Sineshaw, directly from the journal publishers:

Comments are closed.