Michael Tomasello, Trinity ’72, is the James F. Bonk professor of psychology and neuroscience. His new book, “Becoming Human: A Theory of Ontogeny,” draws upon his three decades of research into social cognition and developmental processes in toddlers and great apes to articulate what differentiates humans from other primates. “Becoming Human” was recently honored with the William James Award by the American Psychological Association. The Chronicle sat down with Tomasello to discuss his career and the impact his research has for students at Duke. This interview has been edited for length and clarity.

The Chronicle: Why is it important to understand precisely what makes humans unique on a species level?

Michael Tomasello: It’s a question that everyone is interested in. People wonder where their family came from, where their people came from, all the way back to—where did humans come from? What do we know that great apes do, and what is it that humans do that’s a little different? We live in buildings and have languages and computers, and they’re still in the jungle. It’s been a short evolutionary time, so something really radical happened, but we’re not that different. I sometimes characterize it as a small difference that made a big difference. We are adapted for putting our heads together—cooperating, communicating and learning from other people. We just needed to have a little switch in the head to tune into others in new ways.

TC: You were an undergraduate at Duke—was there anything in particular about your experience here that got you wondering, what do I have in common with all these other Homo sapiens?

MT: I started with these kinds of issues in my first semester. What grabbed me was the idea that cognition—our ability to think—is a biological adaptation, like any other one. That had never occurred to me before. I was really fascinated with animal learning and cognition, and then I took a class on developmental psychology—which I now teach—and the professor brought in some babies, and they’re doing things like what the animals do! They’re like another creature, but they’re going to turn into us. How do they get from this state to the adult state? I thought that process was fascinating.

TC: For many students, college is the first time in your life where you don’t see your family every day. At the same time, the complexity and quantity of social spaces becomes much greater. What would be the most important thing for a college student to understand about our social dynamics?

MT: The tension between cooperation and selfishness is a natural part of who we are. We have a selfish streak—it’s part of our biological nature. But at the same time, to a degree unprecedented in other animals, we are built to cooperate. We are built to care about others, depend on others and have others depend on us. We trust one another. That’s what we have to navigate in our social world. There are times when you have to shut out other people and just look out for yourself.

TC: That’s fascinating because, even a few generations ago, you might not have had students talking about mental health the way we do—thinking that you should make space for yourself and that doing so doesn’t have to be viewed as selfish.

MT: That’s right—one of the key concepts, evolutionarily, is interdependence. If we depend on one another, we need to take care of one another. If you depend on me, then being nice to you partly means I need to take care of myself so that I can be there for you. If I’m having a mental health crash, then that’s bad for you as well if you’re depending on me. That interdependence is just part of human behavior.

TC: I’ve talked with several students about facing imposter syndrome during their time at Duke. Is imposter syndrome a natural part of humans having social identities and lifestyles?

MT: Imposter syndrome starts going away as you interact with others more. It’s important for students to go to academic conferences, for example—you meet people who’ve written the textbooks, and you think they’re way up there, but when you hear them give talks they make mistakes, and you see they’re not as high up as you thought. Then when you present your talk or poster, you get feedback, and you realize they thought your idea was pretty good! You bring them down a few notches and bring yourself up a few notches. There are individual differences with how easy imposter syndrome is to overcome, but recognize that this is part of the way it works. You just plunge in and do things, and it will get better.

TC: One word you often hear in association with our political discourse is that it’s dehumanizing. On a related note, in “Becoming Human,” you discussed how humans have shared agency—we have communal aspects of our identities, and labeling others as a common enemy can be a way to bring people closer. So, it seems dehumanizing others is itself a uniquely human behavior. How does that fit into our understanding of what makes us human?

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MT: There’s a key transition that happened in human evolution. For 98% of our history, we were hunter-gatherers. We lived in groups that were one big family—we didn’t have private property, hardly any. It was all communal. About 10,000 years ago, we get agriculture. We get cities, we get people coming to the food and we get a stratified society. This is Karl Marx’s basic theory, that we get people who have capital and they have power over people without capital.

Very late in the evolutionary process, we get social stratification—people striving for social status within the group. We get this competitive element coming back into the cooperative element. So, there are two sources of selfishness: one is our biological chimp roots, and the other one is competing for status in our culture, which is a very recent phenomenon in humanity.