Table Of ContentALSO BY ROBERT M. SAPOLSKY
Monkeyluv and Other Essays on Our Lives as Animals
A Primate’s Memoir
The Trouble with Testosterone and Other Essays on the Biology of the Human
Predicament
Why Zebras Don’t Get Ulcers: A Guide to Stress, Stress-Related Diseases, and
Coping
Stress, the Aging Brain, and the Mechanisms of Neuron Death
PENGUIN PRESS
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Copyright © 2017 by Robert M. Sapolsky
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Illustration credits appear here.
Library of Congress Cataloging-in-Publication Data
Names: Sapolsky, Robert M., author.
Title: Behave: the biology of humans at our best and worst / Robert M. Sapolsky.
Description: New York: Penguin Press, 2017.
Identifiers: LCCN 2016056755 (print) | LCCN 2017006806 (ebook) | ISBN 9781594205071 (hardback) |
ISBN 9780735222786 (ebook)
Subjects: LCSH: Neurophysiology. | Neurobiology. | Animal behavior. | BISAC: SCIENCE / Life
Sciences / Biology / General. | SOCIAL SCIENCE / Criminology. | SCIENCE / Life Sciences /
Neuroscience.
Classification: LCC QP351 .S27 2017 (print) | LCC QP351 (ebook) | DDC 612.8–dc23
LC record available at https://lccn.loc.gov/2016056755
Interior Illustrations by Tanya Maiboroda here, here, here, here, here, here, here, here, here, here, here,
here, here, here, here, here, here, here, here, here, here, here, here, here, here, here
Version_1
To Mel Konner, who taught me.
To John Newton, who inspired me.
To Lisa, who saved me.
Contents
Also by Robert M. Sapolsky
Title Page
Copyright
Dedication
INTRODUCTION
One THE BEHAVIOR
Two ONE SECOND BEFORE
Three SECONDS TO MINUTES BEFORE
Four HOURS TO DAYS BEFORE
Five DAYS TO MONTHS BEFORE
Six ADOLESCENCE; OR, DUDE, WHERE’S MY FRONTAL CORTEX?
Seven BACK TO THE CRIB, BACK TO THE WOMB
Eight BACK TO WHEN YOU WERE JUST A FERTILIZED EGG
Nine CENTURIES TO MILLENNIA BEFORE
Ten THE EVOLUTION OF BEHAVIOR
Eleven US VERSUS THEM
Twelve HIERARCHY, OBEDIENCE, AND RESISTANCE
Thirteen MORALITY AND DOING THE RIGHT THING, ONCE YOU’VE
FIGURED OUT WHAT THAT IS
Fourteen FEELING SOMEONE’S PAIN, UNDERSTANDING SOMEONE’S PAIN,
ALLEVIATING SOMEONE’S PAIN
Fifteen METAPHORS WE KILL BY
Sixteen BIOLOGY, THE CRIMINAL JUSTICE SYSTEM, AND (OH, WHY
NOT?) FREE WILL
Seventeen WAR AND PEACE
EPILOGUE
Acknowledgments
Appendix 1: Neuroscience 101
Appendix 2: The Basics of Endocrinology
Appendix 3: Protein Basics
Glossary of Abbreviations
Notes
Illustration Credits
Index
About the Author
Introduction
T
he fantasy always runs like this: A team of us has fought our way into his
secret bunker. Okay, it’s a fantasy, let’s go whole hog. I’ve single-handedly
neutralized his elite guard and have burst into his bunker, my Browning machine
gun at the ready. He lunges for his Luger; I knock it out of his hand. He lunges
for the cyanide pill he keeps to commit suicide rather than be captured. I knock
that out of his hand as well. He snarls in rage, attacks with otherworldly
strength. We grapple; I manage to gain the upper hand and pin him down and
handcuff him. “Adolf Hitler,” I announce, “I arrest you for crimes against
humanity.”
And this is where the medal-of-honor version of the fantasy ends and the
imagery darkens. What would I do with Hitler? The viscera become so raw that I
switch to passive voice in my mind, to get some distance. What should be done
with Hitler? It’s easy to imagine, once I allow myself. Sever his spine at the
neck, leave him paralyzed but with sensation. Take out his eyes with a blunt
instrument. Puncture his eardrums, rip out his tongue. Keep him alive, tube-fed,
on a respirator. Immobile, unable to speak, to see, to hear, only able to feel. Then
inject him with something that will give him a cancer that festers and pustulates
in every corner of his body, that will grow and grow until every one of his cells
shrieks with agony, till every moment feels like an infinity spent in the fires of
hell. That’s what should be done with Hitler. That’s what I would want done to
Hitler. That’s what I would do to Hitler.
—
I’ve had versions of this fantasy since I was a kid. Still do at times. And when I
really immerse myself in it, my heart rate quickens, I flush, my fists clench. All
those plans for Hitler, the most evil person in history, the soul most deserving of
punishment.
But there is a big problem. I don’t believe in souls or evil, think that the
word “wicked” is most pertinent to a musical, and doubt that punishment should
be relevant to criminal justice. But there’s a problem with that, in turn—I sure
feel like some people should be put to death, yet I oppose the death penalty. I’ve
enjoyed plenty of violent, schlocky movies, despite being in favor of strict gun
control. And I sure had fun when, at some kid’s birthday party and against
various unformed principles in my mind, I played laser tag, shooting at strangers
from hiding places (fun, that is, until some pimply kid zapped me, like, a
million times and then snickered at me, which made me feel insecure and
unmanly). Yet at the same time, I know most of the lyrics to “Down by the
Riverside” (“ain’t gonna study war no more”) plus when you’re supposed to clap
your hands.
In other words, I have a confused array of feelings and thoughts about
violence, aggression, and competition. Just like most humans.
To preach from an obvious soapbox, our species has problems with violence.
We have the means to create thousands of mushroom clouds; shower heads and
subway ventilation systems have carried poison gas, letters have carried anthrax,
passenger planes have become weapons; mass rapes can constitute a military
strategy; bombs go off in markets, schoolchildren with guns massacre other
children; there are neighborhoods where everyone from pizza delivery guys to
firefighters fears for their safety. And there are the subtler versions of violence
—say, a childhood of growing up abused, or the effects on a minority people
when the symbols of the majority shout domination and menace. We are always
shadowed by the threat of other humans harming us.
If that were solely the way things are, violence would be an easy problem to
approach intellectually. AIDS—unambiguously bad news—eradicate.
Alzheimer’s disease—same thing. Schizophrenia, cancer, malnutrition, flesh-
eating bacteria, global warming, comets hitting earth—ditto.
The problem, though, is that violence doesn’t go on that list. Sometimes we
have no problem with it at all.
This is a central point of this book—we don’t hate violence. We hate and
fear the wrong kind of violence, violence in the wrong context. Because violence
in the right context is different. We pay good money to watch it in a stadium, we
teach our kids to fight back, we feel proud when, in creaky middle age, we
manage a dirty hip-check in a weekend basketball game. Our conversations are
filled with military metaphors—we rally the troops after our ideas get shot
down. Our sports teams’ names celebrate violence—Warriors, Vikings, Lions,
Tigers, and Bears. We even think this way about something as cerebral as chess
—“Kasparov kept pressing for a murderous attack. Toward the end, Kasparov
had to oppose threats of violence with more of the same.”1 We build theologies
around violence, elect leaders who excel at it, and in the case of so many
women, preferentially mate with champions of human combat. When it’s the
“right” type of aggression, we love it.
It is the ambiguity of violence, that we can pull a trigger as an act of hideous
aggression or of self-sacrificing love, that is so challenging. As a result,
violence will always be a part of the human experience that is profoundly hard
to understand.
This book explores the biology of violence, aggression, and competition—
the behaviors and the impulses behind them, the acts of individuals, groups, and
states, and when these are bad or good things. It is a book about the ways in
which humans harm one another. But it is also a book about the ways in which
people do the opposite. What does biology teach us about cooperation,
affiliation, reconciliation, empathy, and altruism?
The book has a number of personal roots. One is that, having had blessedly
little personal exposure to violence in my life, the entire phenomenon scares the
crap out of me. I think like an academic egghead, believing that if I write
enough paragraphs about a scary subject, give enough lectures about it, it will
give up and go away quietly. And if everyone took enough classes about the
biology of violence and studied hard, we’d all be able to take a nap between the
snoozing lion and lamb. Such is the delusional sense of efficacy of a professor.
Then there’s the other personal root for this book. I am by nature majorly
pessimistic. Give me any topic and I’ll find a way in which things will fall apart.
Or turn out wonderfully and somehow, because of that, be poignant and sad. It’s
a pain in the butt, especially to people stuck around me. And when I had kids, I
realized that I needed to get ahold of this tendency big time. So I looked for
evidence that things weren’t quite that bad. I started small, practicing on them—
don’t cry, a T. rex would never come and eat you; of course Nemo’s daddy will
find him. And as I’ve learned more about the subject of this book, there’s been
an unexpected realization—the realms of humans harming one another are
neither universal nor inevitable, and we’re getting some scientific insights into
how to avoid them. My pessimistic self has a hard time admitting this, but there
is room for optimism.
