The title of this blog post emulates the titles of several of Prof. Satoshi Kanazawa's paper. To take a random sample of this: 'Why liberals and atheists are more intelligent', 'Why Night Owls Are More Intelligent', 'Why More Intelligent Individuals Like Classical Music', 'Why Beautiful People Are More Intelligent.' or - his latest installment - the retracted blogpost in Psychology Today, which, after initial screening was rephrased as 'Why Are Black Women Rated Less Physically Attractive Than Other Women, But Black Men Are Rated Better Looking Than Other Men?'
Note that in each case, Prof. Kanazawa takes a controversial statement that needs to be proven as already established, and promises an evolutionary explanation of why the statement is true. Unfortunately, in many cases, the statistical data do not really support the controversial statement in the first place, as was shown in a re-analysis of the data of the retracted paper.
My question today is though: why do not all the other (dubious) papers spark the same amount controvery? Should we be OK with the assumption that less beautiful people being less intelligent, or with the conclusions in the paper "Why liberals and atheists are more intelligent"? This paper which appeared in a peer-reviewed scholarly journal, Social Psychology Quarterly, basically says that people who are more religious are less intelligent, and offers a (to my mind ad hoc) evolutionary explanation for this. I skimmed the web for cries of outrage at this paper, but what I found mostly positive assessments, not just on atheist-friendly blogs but also on science blogs, such as here.
Yet, a re-evaluation of the experimental design indicates serious methodological problems with the study. For example, in study 1, Kanazawa did not use fine-grained measures of religiosity (merely the extent to which people consider themselves religious), and that he used two protocol that were designed to study verbal intelligence, however, he generalized these findings to make statements about the participants' general intelligence. The degree to which verbal intelligence is a good indicator of general intelligence remains unclear in cognitive psychology. Moreover, he makes the substantial assumption that religiosity is the default, standard mode of thinking, whereas atheism is evolutionarily novel. I have argued against this naturalness of religion elsewhere, but here it suffices to say that this is a controversial assumption even among cognitive scientists who study the evolutionary origins of religion.
In sum, a scientific study that could be equally hurtful and damaging to some people as the study on attractiveness in black women was reported and accepted without question. This can be problematic, as, at least in Belgium and The Netherlands, politicians get away with saying that people who practice some religions (notably Islam) are less intelligent, more backward (etc.), and they argue that it is not racist, since they do not target an ethnic minority, but are merely making statements about the effects of culture. It just goes to show that this type of 'research' can also be potentially hurtful and damaging to some people, not just research that is overtly racist.