Robert Sapolsky writes like the experienced teacher he is—he’s knowledgeable, affable, and precise, at once informal and all business. In the acknowledgements we read that he worked up the material for this book in a “small seminar that I taught a few times.” According to Wikipedia, Sapolsky “is currently a professor of biology, and professor of neurology and neurological sciences and, by courtesy, neurosurgery, at Stanford University. In addition, he is a research associate at the National Museums of Kenya.”
I knew of Sapolsky from reading one of his earlier books, A Primate’s Memoir (2002). That book was both a summary of his experiences studying wild baboons in Kenya for many years, and also an account of his experiences living and traveling in Africa. I liked the way it combined science writing with a more general assessment of how the world is. I liked it so much that I gave copies to a couple of people—including my mother. When I asked her how she liked it, she wanted to know why I would think she would like a book about monkeys. My bad—she’s not fond of monkeys, apparently. I didn’t see any point in suggesting that baboons are a lot like people in many ways—ways that tend not to be flattering to our sense of being civilized, reasonable beings.
Sapolsky’s latest book, Behave, is another matter altogether, a daunting tome of over 700 pages. After finishing Behave, I retain my high opinion of its author, though I did have that “school’s out” sense of liberation when I got to the last page. Sapolsky aims high. His goal is to identify and describe—encompass—every factor that can influence a human being’s behavior, from discrete physical elements like neurotransmitters and hormones, on up through genes and evolution to such purely nonmaterial factors as empathy, language, and religion. He makes a convincing case that it’s most often the interaction between multiple factors that counts the most, just as it’s ecosystems, and not individual species, that matter most when you’re talking about sustaining natural environments on earth. The problem for me is that I think he was more determined to make an airtight case, backing up his assertions with copious evidence and citations, than he was to write a great book. I accept that, though I’d have preferred a great book.
The challenge in trying to understand human behavior is that there is no easy way to be objective, to stand outside ourselves, just as you can’t really describe an airplane while you’re flying in it. Sapolsky has one effective strategy for gaining a measure of objectivity—he knows of many cases where animals, typically primates, demonstrate behaviors that we think of as typically human. For example, there’s “stress-induced displacement aggression”:
Shock a rat and it’s glucocorticoid levels and blood pressure rise; with enough shocks, it’s at risk for a ‘stress’ ulcer. Various things can buffer the rat during shocks—running on a wheel, eating, gnawing on wood. But a particular effective buffer is for the rat to bite another rat. … Among baboons, for example, nearly half of aggression is this type—a high ranking male loses a fight and chases a subadult male, who promptly bites a female, who then lunges at an infant.
And then, to drive the point home:
Humans excel at stress-induced displacement aggression—consider how economic downturns increase rates of spousal and child abuse. Or consider a study of family violence and pro football. If the local team unexpectedly loses, spousal/partner violence increases 10 percent soon afterward.
Sapolsky looks hard to find the bright side. In discussing whether it might ever be possible for humans to become less aggressive and warlike, he tells of a particular troop of baboons that he once observed. The more aggressive males in this troop took to visiting a garbage dump behind a hotel, and, as a result of eating tainted meat, came down with tuberculosis and died. Without its most aggressive males, the troop became more cooperative and tolerant. Even after new males arrived to replace the casualties, this mellower behavior persisted. Sapolsky isn’t suggesting that baboons can become a more peaceful species. Their typical level of aggression is an appropriate adaptation to their environment. But he notes that “if baboons unexpectedly show this much social plasticity, so can we. Anyone who says that our worst behaviors are inevitable knows too little about primates, including us.”
Behave is full of studies—that is, Sapolsky tells us how people behaved when subjected to behavior studies by social scientists. For example, he cites one study that found that the percent of court cases where judges rule in favor of defendants drops from 65% first thing in the morning to 0% just before lunch, when judges are hungry and subject to “mental depletion.” After lunch, the rate of favorable rulings returns to 65%. This study was published in the authoritative and eminent “Proceedings of the National Academy of Sciences of the United States of America.” Undoubtedly there is something to the finding. And yet—0%? If hunger and fatigue can affect us to this extent, how do we ever make it to 2:00 p..m. without all hell breaking loose?
Sapolsky’s standard practice is to describe experiments in which subjects are asked to do something or react to a situation while having their brain activity monitored. Sapolsky then tells us which areas of the brain were active and from that draws conclusions. For example, if the amygdala lights up, it indicates that the subject’s more primitive mind, having to do with fear and aggression, is involved. Whereas if neurons fire in the prefrontal cortex, it correlates with the rational mind, where tolerance and self-control originate. I kept imagining a kind of control room with a huge transparent three-dimensional model of the human brain, with different colored lights flashing in different areas. Sapolsky is rarely if ever skeptical about such studies. But how authentic can your behavior be when you’re hooked up to a brain scanner? Here’s a representative paragraph:
Enough is known about the neurobiology of religiosity that there’s even a journal called Religion, Brain, and Behavior. Reciting a familiar prayer activates a mesolimbic dopaminergic system. Improvising one activates regions associated with Theory of Mind, as you try to understand a deity’s perspective (“God wants me to be humble in addition to grateful; better make sure I mention that”). Moreover, more activation of this Theory of Mind network correlates with a more personified image of a deity. Believing that someone is faith healing deactivates the (cognitive) dlPFD, suspending disbelief. And performing a familiar ritual activates cortical regions associated with habit and reflexive evaluation.
Reading such passages made me edgy. (I think my amygdala must have been firing.) I have no grounds to dispute any of the findings, but I’m just not comfortable with such a mechanical perspective on human behavior. At some point, it becomes reductive. And it makes me worry about where such intricate knowledge of the brain might lead, what kinds of drugs and therapies might result.
Why, look you now, how unworthy a thing you make of me! You would play upon me; you would seem to know my stops; you would pluck out the heart of my mystery; you would sound me from my lowest note to the top of my compass: and there is much music, excellent voice, in this little organ; yet cannot you make it speak. 'Sblood, do you think I am easier to be played on than a pipe? Call me what instrument you will, though you can fret me, yet you cannot play upon me.
That’s Hamlet, in Act 3 scene 2. So Behave was clearly not the ideal book for me. But I can’t say I didn’t learn a lot from it. For example, if I’m ever arraigned before a judge at 11:30 a.m., I’ll be sure to ask for an injunction. But I’ll bring a sandwich for the judge just in case.
