Darwin’s Duel with Descartes
Wade’s book is, first and foremost, a courageous but flawed attempt to grapple with a politically divisive but scientifically important topic: recent and regional human evolution. To our knowledge, it is the first of its kind: A mainstream book written by a respectable scientific journalist about racial variation in cognition and temperament. Ranging from provocative speculations to cautious equivocations, A Troublesome Inheritance is an entertaining, informative, but inconsistent challenge to orthodoxy. Whatever its shortcomings, it is essential reading for anyone who applies evolutionary principles to human behavior.
The second half of Wade’s book illustrates some of its flaws. Wade’s hypotheses about the social and institutional effects of racial variation are, of course, perfectly legitimate scientific hypotheses; however, they are undeniably bold, and they confront the heavily fortified garrison of selective dualism that dominates mainstream academic and intellectual discourse. Convincing others that the mainstream position is not only incorrect but also worth challenging probably requires a more impressive armamentarium than Wade provides. The book would have been stronger if Wade had more slowly and carefully built his argument that there are important racial variations in cognitive and temperamental traits before speculating about their role in human history. As it is, Wade’s book is fairly impressionistic, which makes it enjoyable to read, but not as rigorous as it probably needed to be.
As noted above, Wade is strangely dismissive of research about the effect of IQ differences among human groups on economic, institutional, and cultural variables (see pp. 189-193). Although the research on IQ differences is controversial and is far from definitive, it is nevertheless more copious and rigorous than research on any of the putative temperamental differences Wade adduces to explain institutional differences among human groups (Jensen, 1998; Lynn 2006; Rushton and Jensen, 2005; but see Nisbett et al., 2012). It is possible that Wade didn’t want this contentious issue to overshadow the rest of his book, but this contradicts his explicit goal of speaking candidly about human variation and its effects on social institutions. Furthermore, some of Wade’s own speculations are likely to be equally contentious and controversial. Whatever the reason, Wade is selectively skeptical of data that find a relation between institutional quality, work productivity, GDP, economic freedom, and IQ (Gottfredson, 1997; Lynn and Vanhanen, 2012). This puts him at odds with what has become a productive research paradigm (Rindermann, 2013). Of course, future research is needed to fully tease out the relative contributions of IQ and other temperamental traits on social institutions, productivity, and GDP (Stolarski, Zajenkowski, and Meisenberg, 2013). Wade may turn out right, but the current data suggest that his dismissal of the explanatory power of IQ is premature.
It is understandable that many academics and intellectuals are trepidatious about frankly addressing the possibility that groups vary on socially valued traits such as athleticism, self-control, or intelligence. However, the tendency of some intellectuals to denounce those who study such topics–to besmirch their reputations with accusations of racism–is inexcusable. We cannot possibly allay all concerns about this topic, but we do believe that:
1) It would be remarkable if groups did not vary on some socially valued traits.
2) It does not promote the interests of society or of science to deny such variation simply because it makes some people uncomfortable.
3) It is important for academics to study group differences and to educate responsibly the public about what they mean (see Haidt, 2009).
Wade has written a fascinating, challenging, and provocative book with a simple message: Evolution is recent, regional, and it doesn’t stop at the human neck. For many decades now, social scientists have protected themselves from this nearly inescapable implication by adhering to a form of selective dualism. Wade should be applauded for challenging this flawed but convenient stopgap. A Troublesome Inheritance is not a perfect book. We wish it had been a bit more systematic and rigorous, and we fear that Wade’s fascinating speculations will be too easily swept away by streams of outrage and indignation because he failed to provide stronger scaffolding. Nevertheless, his book should encourage public conversation about the important and complicated topic of racial variation. The celebration of human diversity should go hand in hand with the honest and rigorous study of such diversity.