Editor’s Note: Dr. Samuel T. Wilkinson is Associate Professor of Psychiatry at Yale University, where he also serves as Associate Director of the Yale Depression Research Program. His articles have been featured in The New York Times, The Washington Post, and The Wall Street Journal. Wilkinson is the author of Purpose: What Evolution and Human Nature Imply about the Meaning of Our Existence.
[Burnett]: As a medical school professor whose research focuses on depression, you’ve no doubt interacted with many individuals whose biological needs are fully met– they have adequate food, housing, income, and social support, and yet they are crippled with a sense that their lives are meaningless. Do you find it peculiar that evolution could have produced a creature whose livelihood depends on something so intangible?
[Wilkinson]: It’s certainly the case that human beings have a need to find meaning and purpose in life for optimal mental health and well-being. Related to this, many scholars of human nature have also noted we have a God-shaped hole in our heart. In other words, we have a natural inclination to believe in (and even seek) something beyond ourselves or even our physical world. A purely secular explanation would hypothesize that this psychological inclination helped primitive human groups work together and become more cohesive, and hence it enhanced their survival. I’m a bit agnostic as to whether evolution is responsible for the need to seek purpose and meaning. But I would counter the religious skeptic by saying (borrowing logic from C. S. Lewis), that if we were created with a desire for something, then that something probably exists. A baby feels hungry, there is such a thing as food. I have a God-shaped hole in my heart, well there is such a thing as God. I have no qualms ascribing to evolution the creation of both the hunger for food and the inclination to seek meaning and purpose in life (as well as God).
How could evolution have any purpose beyond survival and reproduction?
Most of the top thinkers in evolution—including Stephen J. Gould and Edward Wilson—have argued explicitly that there is no overarching purpose to our existence (other than survival and reproduction). This argument is grounded in the assumption that evolution had no direction and is totally random. But the last 30 years of evolutionary biology has seen an explosion in discoveries that challenge the randomness of evolution. This is most apparent in the work of Cambridge biologist Simon Conway Morris, who has uncovered hundreds of remarkable examples where nature has independently evolved the same patterns over and over again. There seem to be higher-order principles which have constrained, even guided, evolution to go in certain directions. Life as we know it may well have been inevitable.
We often hear in public discourse that promiscuity (particularly among males) is natural, whereas long-term monogamy is an artificial construct. How do you understand the tension between human promiscuity and monogamy?
From an evolutionary lens, human promiscuity is very easy to explain. An evolving male hominid who impregnated many female partners would obviously reap significant evolutionary benefit. But humans, including males, also have the capacity for long-term monogamy. And there is a biological aspect to this, too. The best explanation for how this happened is that nature repurposed the psychological architecture initially used for attachment between a mother and her infant. Several lines of evidence support this, including the fact that the type of relationship you have with your primary caregiver (anxious, secure, or avoidant) predicts the type of relationship you will have with your spouse. There is also evidence from neurobiology. In every mammal that has been studied, one of the key purposes of oxytocin is to promote mother-infant bonding. In those rare mammalian species that have developed monogamy (including ourselves), oxytocin promotes long-term female-male bonding. It appears that oxytocin expanded its portfolio relatively recently (from an evolutionary time scale) to help undergird monogamy. But, as we know all too well, our capacity for monogamy has not extinguished the desire for sexual diversity. Evolution has left us with competing desires, both of which are impossible to satisfy simultaneously. Many poets, authors, and jealous lovers have recognized this, often expressing this conflict as the struggle between lust and love.
You make the case that fatherhood is an important social role in a well-functioning society. How do you square that with the fact that more people than ever are electing not to have children in order to pursue other fulfilling opportunities?
At this point, there is a huge amount of evidence to show that helping tie men to their biological children and thereby enhancing their roles as fathers is a really important social goal. The economist Melissa Kearney just published a book that references this—The Two Parent Privilege (2023). But hers was just one in a long line of data-heavy books that make similar arguments, including Fatherless America (1994) by David Blankenhorn, Life Without Father (1996) by David Popenoe, and The Case for Marriage (2000) by Linda Waite and Maggie Gallagher. Former President Barrack Obama has similarly highlighted the importance of fatherhood, in some cases linking the decline of fatherhood as a root cause for many of our society’s most urgent social problems (see, for instance, his address from February 2013 at Hyde Park Academy in Chicago).
The fact that fatherhood is important does not necessarily make it easy to sustain. As human beings, we are pulled in lots of directions. Today, with reliable contraception and (in Western culture) an over-emphasis on self-fulfillment, many people do choose to forego having children. Having and raising children is incredibly challenging, but most friends and colleagues I speak with admit that it’s also the most rewarding endeavor they’ve ever undertaken. From a biological perspective, there is an inextricable relationship between the immense sacrifice required to raise children and the deep love parents experience as a part of the process. This is the how evolution shaped us. This is the way we were created.
Many people believe that any sense of purpose or meaning for human life is completely subjective and self-determined. Based on what you know of human biology, could there be anything universal or objective about human purpose?
Certainly, there’s a large amount of evidence showing that evolution was not a completely random process (even Richard Dawkins concedes this point). That gets rid of a long-standing obstacle to purpose that has been the assumption of orthodox biology since Darwin. My chief argument is that the way evolution has shaped us and endowed us with competing dispositions (selfishness and altruism, aggression and cooperation, lust and love) combined with the empirical observation that we have free will strongly implies that there is a universal purpose to our existence. This purpose is to choose between the good and evil inherent within us. Life, it would seem, is a test.
Some people believe that humans are fundamentally good, but they are corrupted by society. Others think that humans are fundamentally flawed, and that social institutions such as religion and government must keep them in check. But you argue that evolution has given all of us dual natures—we are naturally selfish and generous, violent and compassionate, etc. What are the implications of having these competing instincts within ourselves?
The two viewpoints of human nature you reference—commonly attributed to Jean Jacque Rousseau (the “noble savage”) and Thomas Hobbes (man is “nasty, brutish, short”)—both have some truth to them. In a very real way, nature has endowed us with immense capacities for good, but also for evil. And culture can go either way as well, influencing us for better or for ill. A lot of scholars of human nature have observed this dichotomy, but so far as I know, none have concluded that this is related to the purpose of our existence. Writes Harvard anthropologist Richard Wrangham:
“A great oddity about humanity is our moral range, from unspeakable viciousness to heartbreaking generosity. From a biological perspective, such diversity presents an unsolved problem. If we evolved to be good, why are we also so vile? Or if we evolved to be wicked, how come we can also be so benign?” (from The Goodness Paradox, 2019, page 4)
The argument I make is that we are this way because this life is a test. We are meant to choose between these competing dispositions within us.
How is human violence different from violence elsewhere in the animal kingdom?
Human violence is much more premeditated and less impulsive compared to animals (especially compared to other primates). Our ability to cooperate is extraordinary, and this is only possible because we have low levels of impulsive violence. A though experiment by anthropologist Sarah Hrdy illustrates this well. Hrdy imagines what it would be like if you tried to get 200 chimpanzees to board an airplane together. The result would be violent chaos. You would be lucky, she notes, “to disembark with all ten fingers and toes still attached” (from Mothers and Others, 2009).
Yet such an occurrence happens thousands of times per day in human societies, with very few instances of this type of impulsive violence. However, the boarding of an airplane is preceded by an intense security and screening procedure. This process is designed precisely to prevent less impulsive but more deadly forms of aggression by would-be hijackers and terrorists. Terrible examples of this type of aggression come all too quickly to mind.
In our fragmented society, everyone wants to be happy, but we can’t agree about how to do it. Are there any essential ingredients for human happiness and societal harmony independent of one’s cultural or political persuasions?
The key ingredient to happiness and well-being is relationships. A huge amount of psychological data has concluded this. (See, for instance, The Good Life: Lessons from the World’s Longest Scientific Study of Happiness by Robert Waldinger and Marc Schulz.) The unique argument I make is where this comes from in a biological sense. Why do relationships lead to happiness? If you believe in the most up-to-date scientific theories of human origins, on some level, this must come from our evolution. On one hand, strong social connections have always served us so well. Our ancestors likely faced a range of unpredictable challenges. Rapidly changing weather, injury, and attacks from wild animals all made life extremely dangerous. Those groups and families who formed strong social connections were more likely to survive. It’s also likely an extension of the necessarily deep and loving relationships that human parents have had to develop with their young children to ensure their survival. Some might see this as a cynical perspective: that parents only love their children because they carry their genes. I would counter and frame it by saying that this is how the strongest forms of love in the flesh were created: through family relationships.
