How Evolutionary Psychology Can Make You Look Like an Ass

There is something about evolutionary psychology (EP) that makes it very attractive to non-psychologists (and to undergraduate psych majors -- you should see them rushing to register for EP courses). I've never been entirely sure what it is about EP that makes non-experts find it so fascinating, and more often than not, swallow it's claims without hesitation. Perhaps it's the simplicity and intuitiveness of many of the explanations. Cheating is bad, and harmful, therefore it is adaptive for us to have evolved a mechanism for detecting it. That's pretty simple and intuitive, right? Of course, this is one of the many reasons that most psychologists don't seem to find EP very attractive. The explanations generally rely on little more than intuition bolstered by sketchy, usually non-experimentally derived data. A careful review of the EP literature would give a scientist little confidence in its claims. However, there are plenty of non-psychologists who are happy to read some trade books on EP, and treat it as gospel. Doing so leads them to come up with all sorts of nonsensical arguments about human behavior. This is especially true when EP "theories" are used to make political arguments, as was the case in a recent essay by Will Wilkinson for the Cato Institute.

Now Wilkinson's formal training is in philosophy, and while he does cite three books on EP and politics, making it reasonable (or at least less charitable) to assume that he's read something on the topic, it's quite clear that his knowledge of EP is minimal. We see this, for instance, in his citing of Oliver Goodenough and Kristin Prehn, whose name he misspells, as the sources of original research on the detection of moral transgressions, when, in fact, she has not published any such research, only a review of the literature for a special issue of a philosophy journal. He furthermore cites the Tooby and Cosmides' social exchange theory, for which there is preciously little (if any) evidence, and even cites their Wason selection task experiments, which have been shown to provide no evidence for their conclusions. He also cites Robert Kurzban's research on social groups as having "shown," which I assume means demonstrated with certainty, that certain aspects of in-group, out-group dynamics have an evolutionary basis. However, if he had even read Kurzban's research, he would know that there are plenty of other alternative theories that explain the data, and that Kurzban has produced preciously little new data in support of his own theory. Given this, we can be sure that Wilkinson is not interested in the science of EP, but only in accepting its claims uncritically, and drawing his own conclusions from them. And that is in fact what he does. I'll go through his major claims, one by one.

1.) The evolutionary basis of in-group, out-group dynamics leads to the following conclusion:

We cannot, however, consistently think of ourselves as members only of that one grand coalition: the Brotherhood of Mankind. Our disposition to think in terms of "us" versus "them" is irremediable and it has unavoidable political implications.

Wilkinson's conclusion is probably true, though it's certainly not new. Social psychologists have been making similar points for decades, without the benefit (burden) of evolutionary stories. In fact, the two evolutionary stories that Wilkinson cites here, the social exchange theory, which can be thrown out due to a lack of evidence, and significant amounts of recalcitrant data, and Kurzban's theories of stigmatization and social categorization, which also has preciously little empirical support, are utterly superfluous in Wilkinson's argument. They're little more than distractions from the real point: that in-group, out-group dynamics appear across cultures, and that understanding them is important if we are to successfully transcend perceived group boundaries.

3.) Wilkinson writes:

There is evidence that greater skill and initiative could lead to higher status and bigger shares of resources for an individual in the EEA. But because of the social nature of hunting and gathering, the fact that food spoiled quickly, and the utter absence of privacy, the benefits of individual success in hunting or foraging could not be easily internalized by the individual, and were expected to be shared. The EEA was for the most part a zero-sum world, where increases in total wealth through invention, investment, and extended economic exchange were totally unknown. More for you was less for me. Therefore, if anyone managed to acquire a great deal more than anyone else, that was pretty good evidence that theirs was a stash of ill-gotten gains, acquired by cheating, stealing, raw force, or, at best, sheer luck. Envy of the disproportionately wealthy may have helped to reinforce generally adaptive norms of sharing and to help those of lower status on the dominance hierarchy guard against further predation by those able to amass power.

Our zero-sum mentality makes it hard for us to understand how trade and investment can increase the amount of total wealth. We are thus ill-equipped to easily understand our own economic system.

These features of human nature—that we are coalitional, hierarchical, and envious zero-sum thinkers—would seem to make liberal capitalism extremely unlikely. And it is. However, the benefits of a liberal market order can be seen in a few further features of the human mind and social organization in the EEA.

This argument borders on the nonsensical. Even if we ignore the merely speculative assertions about the EEA (Environment of Evolutionary Adaptedness), Wilkinson's conclusions simply do not follow from his non-EP premises: humans are coalitional, hierarchical, and envious. In fact, it is the coalitional and hierarchical nature of human groups that makes economic and power hierarchies so natural, and readily accepted by most individuals. Thousands of years of human society demonstrate this, making Wilkinson's ultimate conclusion baffling. Even if we refer to the primate data, we will still come to the conclusion that economic hierarchies are natural, easily understood, and widely accepted. In nonhuman primates, higher-status individuals have access more and better resources (including food and mates), and, in direct contrast to Wilkinson's claim, the best way to move up in the hierarchy is to invest in groups of similarly low status individuals in order to gang up on higher-status individuals. While higher status individuals, in both human and nonhuman species, often do steal and use force to gain resources and maintain their status, it is not automatically assumed that they have done so by "cheating," but instead have done so through natural social processes. It's not surprising, then, that exchange and unequal distributions of wealth have dominated human societies even during the times when group sizes were relatively small, i.e. in the EEA.

In short, then, Wilkinson's premises lead to a conclusion contradictory to his own. In fact, as economists, political scientists, and social psychologists have noted for decades, various systems of economic and political hierarchies flow quite naturally out of our seemingly innate understanding of social hierarchies. This is because they mirror the structure of hierarchical social structures, be it through tradition, the consolidation of power, or the control of production and resources (Habermas has an entire book on this stuff, with no mention of evolution).

4.) Citing a paper he clearly has not read by Goodenough and Prehn, Wilkinson argues that neuroscientific research has demonstrated that we have innate property concepts, out of which property rights naturally flow. This claim is absurd given the data. Even if we did have consistent research demonstrating that certain brain areas are active during reasoning about property rights in adult humans, this would hardly be evidence that property concepts are innate. Furthermore, we have no such evidence! It doesn't appear that the detection of property right violations are any more automatic than other forms of moral reasoning, and the lack of cross-cultural data makes it impossible to know just how natural they are. What we do know about moral cognition and its neural correlates goes against everything Wilkinson says in the section on property rights. In particular, imaging studies of moral reasoning demonstrate that its neural correlates are spread throughout the brain, utilizing brain centers that likely developed for other tasks (e.g., decision making), and that there is likely no "moral reasoning module," much less a "property rights violation module," as Wilkinson implies there is. If Wilkinson had read any of the literature (including the paper by the authors he actually cites), he would know this. In particular, I recommend three papers by William D. Casebeer (one with Patricia Churchland), which are here, here, and here (the third is a fairly extensive literature review), along with this review paper by Greene and Haidt.

5.) Citing social exchange theory again, Wilkinson writes, "The human mind is 'built' to trade." Well, social exchange theory, in all its falsifiedness, certainly doesn't demonstrate this. It is true that reciprocity appears to be universal in humans, though this universality arises largely out of cooperative behavior, not trace specifically. Trade may, then, be a natural offshoot of reciprocity, but nothing here implies that trade is innate.

From there, Wilkinson goes on to argue, taking EP speculations about the EEA as certain truths, that modern capitalism is difficult for most humans to comprehend because we evolved to exist in smaller groups, with all of the features he claims in 1-4. This makes absolutely no sense. First, even during the EEA, when humans did exist in small groups for the most part, inter-group trade was common in some areas, and for at least 10,000 years, it has been the norm (consider early modern human remains found in China that are more consistent with European lineages, indicating trade between two widely different and geographically separated groups). In fact, a more plausible evolutionary story is that this is in fact one of the main reasons why we are so good at detecting cheaters. Trading within groups is fairly safe, because we have guarantees that group members will play by the rules (if they don't, they'll be ostracized or worse), while non-group members, with whom we had to trade on many occasions, could not be automatically trusted. As with his claim that the existence of social hierarchies makes capitalism difficult to comprehend, his arguments here have no real connection to his premises.

The lesson to be learned here, aside from reading about things you cite, is that unless one is willing to critically evaluate research, one shouldn't draw conclusions from it. Wilkinson, and most other non-psychologist EP fans seem to think that it is OK to take EP at its word, without deigning to evaluate the theories, research methods, or data. And what we get from them is the sort of nonsense that Wilkinson's essay represents so well.

(Link to Wilkinson's paper via Positive Liberty.)