Steve Pinker weighs in on the

After I wrote my critique of Subrena Smith's anti-evolutionary-psychology paper this morning-hers titled "Is evolutionary psychology possible?"-I sent the link to Steve Pinker, who's quarantining on Cape Cod. He wrote back with some nice words of approbation, but added a few points. I thought these points were good, relevant and, as the first two weren't made by either me or critic Edward Hagen, I asked Steve if I could quote him. He said yes. So add these criticisms to those leveled this morning. (Steve's words are indented.)

All your points are exactly right. The motive seems to be the slipshod politicizing I exposed 18 years ago in The Blank Slate: if we're blank slates, there can't be differences between races, which would make racism impossible; therefore to combat racism we must believe that humans are blank slates. It fails both in philosophical coherence (racism is not an empirical hypothesis that might be shown to be true or false) and in accuracy - most evolutionary psychologists argue for a universal human nature. Also, a philosophical argument against evolutionary explanations in psychology ultimately falls apart when it unwittingly "refutes" even the most unexceptionable evolutionary explanations, such as sexual desire or protectiveness of children. And ironically, though this argument claims to be based in the philosophy of science, it seems unaware that within that field "argument to the best explanation" is generally considered the only means by which science of any kind is done - science never makes apodictic pronouncements based on a prior list of methodological precepts.

A couple of other observations [about Smith's argument]:

-"Massive modularity" [JAC: a term Smith uses as an inherent part of "Evolutionary Psychology"] is not a term that was ever, to my knowledge, used by an evolutionary psychologist. As far as I know it was coined by that foe of natural selection, the late Jerry Fodor, as a term of abuse (and partly to protect the brand of Modularity, which Fodor introduced to philosophy and cognitive psychology in 1983). I've always argued that "module" is a misleading metaphor; we should be thinking about specialization. The brain isn't spam, but the specialization of information-processing systems, like that of organ systems, needn't be into encapsulated modules (Fodor's definition); the systems have to talk to each other, share subroutines, pass information back and forth, and so on, just like the circulatory system and the digestive system do.

-This is a point in the fine print of EP, forgotten even by many of its practitioners, but the Environment of Evolutionary Adaptedness should not be confused with the Pleistocene or the hunter-gatherer lifestyle - it's a time-weighted composite of selection pressures right up to the present (since natural selection never sleeps). We've spent more of our time as humans in a hunter-gatherer lifestyle, and, ironically for the PC police, the simplifying assumption that "EEA = Pleistocene" guarantees human biological equality, since we were all hunter-gatherers then, whereas different groups transitioned to agriculture and civilization at different times subsequent to then. And so if we continued to evolve since then, some groups could be more biologically adapted than others to literacy, settled life, governance, and so on. So the Pleistocene-EEA idealization is simple and convenient. But it's far from necessary, and I think is an impediment, because it requires being more gratuitously committed to savannah-caveman scenarios. Many selection pressures are more or less unchanged since the dawn of the Holocene - paternity uncertainty, infant care, avoiding toxic foods, securing allies, etc. And for many others the most dramatic dividing line is not Pleistocene-Holocene or hunter-gatherer/agriculture, but urban, educated modernity (knowledge of science and statistics, professional employment, universal information, access to the legal system, modern medical care) versus every other lifestyle. An American 19th century farming village, or a favela or peasant society in the developing world, has pretty much the same face-to-face social network, with a pre-scientific knowledge base and a remoteness from legal and professional institutions, as a hunter-gatherer society 10K years ago. What's key is avoiding the assumption that humanity is adapted to a modern urban or suburban college-educated lifestyle, not assuming that we have the same brains as hunter-gatherers (whether or not we in fact do).

-I think that one important direction of evolutionary psychology (and medicine, and biology in general) is to look for statistical signs of selection in the genome. This showed that the modern version of FOXP2, involved in language and speech, was a target of selection (though not on the recent rapid sweep originally hypothesized, probably earlier). But this method works best in the rare cases where single genes with large effects can be identified. Now that we know that virtually all behavioral variation is under the control of many genes with minuscule individual effects, I wonder whether there are techniques that can assess signs of selection across an entire vector of genes rather than individual genes.