Subrena Smith, an assistant professor of philosophy at The University of New Hampshire, has made a bold claim in the journal Biological Theory (click on screenshot below). She claims to have found a fatal flaw in the practice of evolutionary psychology, one that renders the entire discipline “impossible”. Click below to read the article for free:
Here’s the abstract in which she identifies the flaw (there are actually more than one) and pronounces the discipline “impossible”:
Her article has garnered quite a bit of approbation among those who think that evolutionary psychology is a worthless enterprise, including, apparently, the site Gizmodo, which published a worshipful interview with Smith (click on screenshot below to read it):
Well, has she done what she aimed to: brought down an entire discipline? My judgment is “no—certainly not.” She doesn’t even come close. What she does is list a set of standards that, Smith thinks, must be met for an evolutionary psychology explanation to be credible, and these standards are so rigorous and hard to meet that no study has met them or can meet them. Ergo, evolutionary psychology—done the way she wants—is “impossible.”
I believe that her overly excessive requirements bespeak Smith’s lack of understanding of how evolutionary biology is done. And that, I believe, comes from the fact that Smith is not a practicing scientist, but rather a philosopher, all of whose degrees were in philosophy. I usually don’t bring up credentials when discussing an argument, but I think her concentration on philosophy is relevant to her belief that evolutionary psychology fails to meet all tests of being a scientific field. Philosophers tend to be absolutists who require a
clam claim to follow a set of strict rules.
Let me briefly say that I’m not a wholesale fan of evolutionary psychology, as a lot of it involves adaptive storytelling that is untestable. Often sample sizes are too small to be useful, and confirmation bias is strong. But that doesn’t apply to the whole discipline!
It is not ridiculous to think that, just as our bodies were shaped by natural selection acting on our ancestors, and that some of those ancient morphology persists (the shape of our spine, men being bigger and stronger than women on average, and so on), so our minds have been shaped by natural selection as well, and we still show traces of those evolved behaviors today. (Parental care is an obvious one, as is concern for one’s relatives, and so, I think, are the average differences in sexual behavior of men versus women).
Indeed, Smith seems to agree with me here. She doesn’t object to an evolutionary analysis of human mentation and behavior (“evolutionary psychology” in small letters), but to an extreme form of the discipline that she capitalizes as “Evolutionary Psychology.” The thing is, a lot of us don’t accept “Evolutionary Psychology”, at least as Smith construes it in her paper (my emphasis below):
If the arguments that I have presented in this article are sound, the methodological defects of Evolutionary Psychology are so profound as to be unrectifiable, and consequently Evolutionary Psychology is not possible. Evolutionary psychologists simply do not have the methodological resources to justify the claim that the psychological causes of contemporary behaviors are strong vertical homologs of the psychological causes of corresponding behaviors in the EEA. The result for evolutionary psychology (as contrasted with Evolutionary Psychology) is less clear. No one should contest that the human mind is a product of evolution, and evolution must therefore enter into an explanation of human psychology in some way.
Evolutionary Psychology rests on three pillars: the massive modularity hypothesis, the claim that modular structures evolved as adaptations to recurrent challenges in the EEA, and the tacit assumption that mental structures can be individuated and so license claims about strong vertical homologies. These three components, taken together, are inconsistent with the competing hypothesis that evolution fashioned the human mind as a domain-general or modestly modular learning system.
But if the human mind is a product of evolution, and that evolution impacts human psychology, then she’s already conceded that there’s a valid program of “evolutionary psychology.” What she objects to in the capitalized version are its contentions that “adaptive” modern human behaviors—things like sexual behavior, mate guarding, jealousy, male displays like courting danger and showing off—are represented as “modules” (separable neural networks coding for feelings and behaviors). She also objects to other issues, which I’ll get to presently.
Well, I don’t care much about “modules”; if behaviors are evolved, then there must be some neuronal network that facilitates their appearance. Frankly, I don’t know what a “module” is, but if Smith is right and evolution must explain some of our psychology, then those explanations involve evolution of our nervous system. Modules, in my view, don’t at all need to be separate neuronal “compartments”, for we have no idea of how the brain is structured to produce behaviors. Very different behaviors might involve some of the same neurons.
Smith also claims that evolutionary psychology is different from evolutionary morphology because behaviors, unlike bodies, are flexible, and can vary depending on the environment and other circumstances. But that, too, fails to negate the value of evolutionary psychology. The value of parental care as an evolved trait is not negated because some parents neglect or even kill their children. The evolved difference in male versus human sexual behavior is not negated by the presence of some people, like gays, who fail to conform. The goal of evolutionary psychology should explain general tendencies, not absolutes. This insistence on absolutism and dogmatic programs of proof derives, I think, from Smith’s training in philosophy.
Smith also insists that not only must our behaviors be adaptive now, but we must show that they were adaptive in our ancestors, which of course is impossible (as it is for all traits in all creatures!). Further, and this is her big issue, we must show that the “modules” that produced an adaptive behavior in our ancestors are genetically related to, and the ancestors of, the “modules” we use today when performing the related behavior. This insistence on showing exact evolutionary homology between a behavior and its “module” today and its ancestral “module” in the past is what Smith calls the “matching problem.”
That too is overly stringent: how could we possibly show that the exact neuronal pathways involved in, say, males being promiscuous, are the same as those in our hominin ancestors? Smith is asking too much here. What we can do is use comparative data (do other primates show similar differences in sexual behavior?) as well as concocting tests (e.g., do males who are less promiscuous have fewer offspring?), and, if our predictions and comparative analyses continue to support our hypothesis, then we get increasing confidence in it.
Smith uses the example of greater male than female sexual jealousy as her sole example of Evolutionary Psychology nonsense: males are (and should be) more sexually attentive and jealous of their female partners because they can’t be sure of the paternity of their offspring (females can cheat). In contrast, females are much more sure of the paternity of their offspring, and so shouldn’t worry as much if their partner copulates with another woman. This, too, can be tested: one test (suggested by Matthew Cobb) is to see if this phenomenon obtains in those societies in which people don’t connect sex with reproduction (there are difficulties with that test, of course). There are other tests of the adaptive value of sexual jealousy as well, including measuring reproduction and paternity. The point is that one can do tests that either strengthen or weaken one’s confidence in a hypothesis, and we don’t really need to figure out what is going on in our ancestors so long as the phenomenon there also seems adaptive. And we don’t need to know anything about ancestral versus current “brain modules”.
Evolutionary biology is not about finding absolute truth, but about inference to the best explanation, and that is what Smith fails to understand. I suppose Smith would consider all phylogenies (family trees of species) unreliable unless we have a complete fossil record of all the species involved, including the common ancestors!
Indeed, one example that Smith gives of a trait that to her seems truly evolved by natural selection in humans is the eye-blink reflex. But, as Edward Hagen shows in his critique below, she uses exactly the kind of inference which she says is subsumed in the unreliable methodology of evolutionary psychology: presumed stories about the adaptive value of that reflex, comparative studies of other species, and so on. I will leave you to read Hagen’s critique, which is polite but trenchant, in the pages of The Evolution Institute (click on screenshot below).
Why is a philosopher critiquing evolutionary psychology? While other philosophers, most notably Philip Kitcher, have written valuable critiques because they were concerned about the lax standards of the discipline, Smith has another reason as well. As you might suspect, it’s because she sees Evolutionary Psychology (capital letters) as somehow vindicating racism and sexism. We can’t have that, and so we must dispose of the discipline.
Of course “is”s don’t imply “ought”s, as I keep saying, and no finding of evolutionary psychology could ever tell us how to treat other people morally and legally. But Smith doesn’t seem to see it that way. Rather, she presents a caricature of evolutionary psychology that might have applied in the 19th and early 20th centuries, but doesn’t apply any longer. This is from her interview at Gizmodo (my emphasis):
The evolutionary psychologists I engage with are not silly people. They are thoughtful and philosophical about these matters. However, the attractiveness of evolutionary theory coupled with peoples’ ideological biases forces them to not be as careful as they might be otherwise. I think that the consequences for our world when we misappropriate evolutionary accounts are really serious. People are saying that people of color have smaller brains, which is not true, or that women aren’t as great as men, which is not true... I think we have a special responsibility, when we say evolution made us that way, to recognize that people will read “innate” or “hardwired” as synonymous with evolution. We should be especially careful to not be making claims like these, which can have consequences.
There you have it ladies and gentlemen, brothers and sisters, comrades—a strong objection to evolutionary psychology on the grounds that it facilitates racism and sexism. I don’t think that’s a reason for opposing a scientific discipline, but a reason for opposing the unjustified misuse of a scientific discipline. I, for one, would find it very odd if people like David Buss, Steve Pinker, Robert Trivers, or Randolph Nesse would sign on to the propositions that people of color have smaller brains and that “women aren’t as great as men.” Smith is faulting an entire discipline for the misuse of it by some people—a hundred years ago.