Behave: The Biology of Humans at Our Best and Worst

  • Robert M. Sapolsky
Penguin: 2017. 9781594205071 9781847922168 | ISBN: 978-1-5942-0507-1

Robert Sapolsky's students must love him. In Behave, the primatologist, neurologist and science communicator writes like a teacher: witty, erudite and passionate about clear communication. You feel like a lucky auditor in a fast-paced undergraduate course, where the implications of fascinating scientific findings are illuminated through topical stories and pop-culture allusions.

A Tunisian soldier at a demonstration against the government in January 2011. The army had refused to fire on protestors earlier that month. Credit: Martin Bureau/AFP/Getty

But Behave has also been written to a serious moral end. Sapolsky is seeking to understand why, as a species, humans can ruthlessly pull a trigger or compassionately touch an arm. In this sense, the book joins a genre of evolutionarily inflected works that, since at least the 1960s, have struggled to decide what we are. Are we killer apes burdened by incorrigible instincts towards aggression, or are we as much defined by our capacity for compassion and peaceful resolution of conflict? Sapolsky seeks to move beyond polarizing debate, because it is clear to him that we are both.

Sapolsky's is a biological project at heart. He takes the customary swipe at any social scientist who might believe that humans are born blank slates. But he also has a stern word for the “molecular fundamentalist” who has no time for the allegedly soft findings of the social sciences. Biology matters; so does the cultural and social context within which behaviours unfold. To understand humans at our best and worst, we need the insights of neuroscience, endocrinology, primatology, developmental biology, evolutionary theory, clinical psychology and social psychology. We also — more pointedly — need to understand how they are all “utterly intertwined”.

Given the importance that Sapolsky attaches to context and culture, I was disappointed that he did not engage more with the varied tribes of scholars — historians, anthropologists, scholars of religion and more — who might not be scientists, but who study these things for a living. Maybe he thinks they are just not interested in playing ball. He contends that at least some “weren't thrilled” by the discovery that species such as chimpanzees have a certain kind of culture, and says that they emphasize human-centric definitions to cut out “chimps and other hoi polloi”. He notes that such scholars are also engaged in contentious debates of their own with “postmodernists” that he declines to follow. Rather than wade into their quagmire, he opts instead for an “intuitive” definition of culture favoured by primatologist Frans de Waal: “How we do and think about things, transmitted by nongenetic means.” It seems like a missed opportunity. What have the humanities' debates and struggles to do justice to human culture been all about? Are we so certain that they have nothing to offer Sapolsky's great project?

At 700-plus pages excluding notes, Behave is in a sense two books. The first part is a rich survey of behavioural biology: developmental processes in the brain, the logic of evolutionary theory, the adolescent brain. Then Sapolsky reaches for the bigger, synthetic pay-offs, examining how, together, these insights can enhance our understanding of the forces that lead to tribalism, violence, dehumanization and war — as well as tolerance, empathy and peace. Symbols and ideas matter a lot in this part of the analysis. We learn how metaphors can dehumanize in ways that can lead to atrocity (such as reframing a despised human group as 'cockroaches') and, conversely, how reconciliation is possible when warring groups agree to honour symbols that embody the sacred values of their former adversary (for example, by playing the other group's national anthem).

The analysis is arresting and the writing often moving, but again I hoped for a hand stretched across the science–humanities divide. Why not mine the work of Holocaust scholars and anthropologists of war-torn societies? Why not all hands on deck?

On other big issues, such as free will, Sapolsky struggles with his intellectual commitments as a scientist and his moral commitments to a more humane world. Decades of behavioural biology have demonstrated that we have little, if any, free will “worth wanting” (as philosopher Daniel Dennett puts it). Yet, even if all behaviours are biologically caused, grossly aberrant ones may be particularly constrained. Sapolsky concludes that our approach to people who commit crimes should be therapeutic and not vindictive; “words like 'evil' and 'soul' will be as irrelevant as when considering a car with faulty brakes”.

This leads him to a quandary. If you deny free will when it comes to our “worst behaviours”, you must logically deny it when it comes to our best ones. And Sapolsky can't bring himself to do this. He clings to the “homuncular myth” that humans can transcend their circumstances and do the right thing, even if it is the harder thing. The examples of civil-rights leader Martin Luther King, former South African president Nelson Mandela and less celebrated individuals — anonymous soldiers who negotiated the Christmas truce of the First World War, for example — show us that “we personally can cause change”. But change for good, says Sapolsky, is more likely when we understand what kind of animal we are, as well as which traditional levers designed to enhance moral behaviour work and which ones don't.

Will better knowledge of human behavioural biology create the conditions for more Mandelas? Is the science secure enough? Is science on its own enough? I am sure that Sapolsky will encounter plenty of sceptics, but being a naysayer is always easier than offering a way forward. In the end, it is impossible not to deeply admire a project bold enough to ask an entire field to work to create a more just and peaceful world. Whether or not success is assured, Sapolsky exhorts us all — please, just try.