The Crusade and Its Corruptions: When Anti-Prejudice Science Slips Into Motivated Reasoning

Boas’s influence upon American social scientists in matters of race can hardly be exaggerated. At the same time that racial segregation was being imposed by law in the states of the American South, and eugenics was emerging as a hereditarian solution to social problems. Boas was embarking upon a life-long assault on the idea that race was a primary source of the differences to be found in the mental or social capabilities of human groups. He accomplished his mission largely through his ceaseless, almost relentless articulation of the concept of culture.

History followed different courses for different peoples because of differences among peoples’ environments, not because of biological differences among peoples themselves.

Carleton Coon was one of the greatest anthropologists of the 20th century and a champion of the study of racial differences. In 1961 he was elected president of the American Anthropological Association. It was during this year that Carleton Putnam's infamous book Race and Reason came out. Putnam's book argued that there were significant differences between the races and that this had important political implications. A few anthropologists became upset when they saw the book gain popularity and wanted the AAA to intervene. But they knew that Coon supported the book and that, as a result, having the AAA take action against it would be difficult. So they organized a secret meeting behind Coon's back in order to issue a statement denouncing Putnam's work. Coon found out about the meeting and went to stop it. Upon entering the meeting Coon asked all the association members who had actually read Putnam's book to raise their hands. Only one rose. He then asked for the hands of everyone that had even heard of the book prior to that meeting. Only a few hands rose. None the less, the statement against the book passed. Coon, disgusted by the actions of his peers, resigned from the AAA (1). This incident stands out in the history of science as a particularly clear example of scientists not living up to what people expect of them. People often take what scientists say for granted. They trust that scientists have looked at the evidence rationally and are giving the public as accurate an account of all the relevant facts as they can. When explaining science to laypeople researchers are expected to only make authoritative statements on topics they are knowledgeable of, to not lie about scientific evidence, and to not omit obviously relevant facts. People trust scientists to do these things and so feel comfortable taking what they tell them for granted. (See

The results are quite remarkable. The mean” proportion of the total species diversity that is contained within populations is 85.4%, with a maximum of 99.7% for the Xm gene, and a minimum of 63.6% for Duffy. Less than 15% of all human genetic diversity is accounted for by differences between human groups! Moreover, the difference between populations within a race accounts for an additional 8.3%, so that only 6.3% is accounted for by racial classification. This allocation of 85% of human genetic diversity to individual variation within populations is sensitive to the sample of populations considered. As we have several times pointed out, our sample is heavily weighted with “primitive” peoples with small populations, so that their Ho values count much too heavily compared with their proportion in the total human population. Scanning Table 3 we see that, more often than not, the Hpop values are lower for South Asian aborigines, Australian aborigines, Oceanians, and Amerinds than for the three large racial groups. Moreover, the total human diversity, Hspecies, is inflated because of the overweighting of these small groups, which tend to have gene frequencies that deviate from the large races. Thus the fraction of diversity within populations is doubly underestimated since the numerator of that fraction is underestimated and the denominator overestimated. When we consider the remaining diversity, not explained by within-population effects, the allocation to within-race and between-race effects is sensitive to our racial representations. On the one hand the over-representation of aborigines and Oceanians tends to give too much weight to diversity between races. On the other hand, the racial component is underestimated by certain arbitrary lumpings of divergent populations in one race. For example, if the Hindi and Urdu speaking peoples were separated out as a race, and if the Melanesian peoples of the South Asian seas were not lumped with the Oceanians, then the racial component of diversity would be increased. Of course, by assigning each population to separate races we would carry this procedure to the reductio ad absurdum. A post facto assignment, based on gene frequencies, would also increase the racial component, but if this were carried out objectively it would lump certain Africans with Lapps! Clearly, if we are to assess the meaning of racial classifications in genetic terms, we must concern ourselves with the usual racial divisions. All things considered, then, the 6.3% of human diversity assignable to race is about right, or a slight overestimate considering that Hpop is overestimated. It is clear that our perception of relatively large differences between human races and subgroups, as compared to the variation within these groups, is indeed a biased perception and that, based on randomly chosen genetic differences, human races and populations are remarkably similar to each other, with the largest part by far of human variation being accounted for by the differences between individuals. Human racial classification is of no social value and is positively destructive of social and human relations. Since such racial classification is now seen to be of virtually no genetic or taxonomic significance either, no justification can be offered for its continuance.