Evolutionary psychology produces insights into the human psyche and behavior by comparing evidence on what contemporary human beings are like to deductions about what they would be expected to be like given the selective pressures in operation over the course of our species’ pre-history and history. As an economist who studies problems of human cooperation using game theoretic and experimental tools, I find insights from this way of looking at human nature to be a powerful antidote to the unscientific view of human actors that underlay the leading school of economics in the century leading up to the late 1970s. That view assumed each individual to be an asocial seeker of maximum wealth and avoider of insufficiently compensated effort, with zero concern about others. Real people are highly sensitive to social cues and are often concerned, for example, to avoid being shunned for violation of norms, including the moral norms that help promote group-beneficial behaviors.
While a strong supporter of following evolutionary reasoning where it may lead in shedding light on our natures, I sometimes wince at overly mechanistic understandings of its implications. Sometimes the trouble is mainly semantic: expounders of evolutionary approaches overuse the metaphor of genes having goals to the point where they seem to forget that bits of DNA are mindless and that the metaphor is valid only in an “as if” sense. But I sometimes worry that an expositor has actually forgotten the distinction between a concrete human being and a general aim towards which his genes ought (by the logic of the theory) to dispose him. For example, men are portrayed as wanting to get as many copies of their genes as possible into the future gene pool, and as finding it difficult to be exclusively monogamous for that reason. There’s in fact nothing in sound sociobiological or evolutionary psychological theory that implies that actual individual men have the specific goal of maximally procreating. Rather, the theory implies that most men’s genes would code for proximate forces that, under ancestral conditions, led to having many offspring. The actual individual may find himself with a craving for sex, for example, but he is entirely free to use a condom, undergo a vasectomy, or even to become celibate if he believes this serves worthwhile ends. No number of examples of historical individuals who acted as if hell-bent on maximizing their genetic fitness—no “Genghis Khan and his brother Don,” to quote Bob Dylan—can prove every male a perfect instrument of his genes’ “as if” objectives.
This is not to say that what governs our behavior isn’t oft times unconscious, including tastes that it makes sense for us to have based on our evolutionary histories. Nor is the metaphor that the individual is in some respects an expendable vehicle that its genes ride into the future without its uses. The problem occurs when the goals of the individual are too mechanically equated with the goals that evolutionary logic says her genes should instill her with. While genes predispose towards behaviors that are in accord with the genes’ “as if” long-term “interest,” they work through proximate forces like sexual attraction, pleasure seeking, craving for social status, and the like, forces that are not fully determinative of exact courses of action. Precisely because the human social environment is too complex for us to navigate by instinct alone, our genes control us, insofar as they do, by holding us on their “leash,” but that leash is one with substantial slack. The image of the individual as an agent of his or her genes is a useful one, but in the language of economic theory, there exists a relationship of principal-and-agent between genome and person, such that the genome can incentivize certain actions with a set of rewards and penalties, but it can’t command precise actions in detail. The more that the evolutionary behavioral sciences advance, the more can the complex mental capabilities of human beings allow us to size up our positions as agents and to decide just how slavishly we will serve our genetic master, and in what respects we’ll assert our independence.
If individuals can rebel against their genes by using contraception, concocting artificial sweeteners, or becoming devotees of religions that preach humility rather than status-seeking, what about societies? Does it make sense to talk of groups of people collectively choosing goals such as reducing the incidence of violence, equalizing the opportunities of the sexes, guarding against environmental catastrophes, and preventing the exploitation of individuals of particular ethnicity, sexual preference, or physical or mental ability? To have aspirations as a society makes no sense at all if we’re each slaves to our genetic dispositions and if whatever goals human beings can individually and collectively have are nothing but exact reflections of the “as if” goals of their genes. But an intellectually rigorous, evolutionarily-informed view of human nature and behavior doesn’t actually imply that. The degree of freedom we each enjoy as imperfect agents of our genes implies, on the contrary, that collective deliberation and agreement on goals not unambiguously spelled out in our genomes isn’t beyond the realm of the possible. Those goals, and the methods by which we attempt to achieve them, ought not to be too inconsistent with our natures, if they are to stand a chance of being achieved. But neither must they inevitably be ones that are precisely dictated by our genes.