The Rational Animal: How Evolution Made Us Smarter Than We Think

by Kenrick, Douglas T.

  The Rational Animal

  ALSO BY DOUGLAS T. KENRICK

  Sex, Murder, and the Meaning of Life:

  A Psychologist Investigates How Evolution, Cognition, and Complexity

  Are Revolutionizing Our View of Human Nature (2011)

  Copyright © 2013 by Douglas T. Kenrick and Vladas Griskevicius

  Published by Basic Books,

  A Member of the Perseus Books Group

  All rights reserved. No part of this book may be reproduced in any manner whatsoever without written permission except in the case of brief quotations embodied in critical articles and reviews. For information, address Basic Books, 250 West 57th Street, 15th Floor, New York, NY 10107-1307.

  Books published by Basic Books are available at special discounts for bulk purchases in the United States by corporations, institutions, and other organizations. For more information, please contact the Special Markets Department at the Perseus Books Group, 2300 Chestnut Street, Suite 200, Philadelphia, PA 19103, or call (800) 810-4145, ext. 5000, or e-mail special.markets@perseusbooks.com.

  Designed by Jeff Williams

  Library of Congress Cataloging-in-Publication Data

  Kenrick, Douglas T.

  The rational animal : how evolution made us smarter than we think / Douglas T. Kenrick and Vladas Griskevicius.

  pages cm

  Includes bibliographical references and index.

  ISBN 978-0-465-04097-1 (e-book) 1. Reasoning (Psychology) 2. Decision making. 3. Evolutionary psychology. I. Griskevicius, Vladas. II. Title.

  BF442.K46 2013

  153—dc23

  2013008954

  DOUG:

  For my sons, Dave and Liam,

  who taught me a deeper lesson about rationality.

  For my wife, Carol, who puts up with my irrationality.

  For my mother-in-law, Jean Luce, who contributed the most

  rational portion of Liam’s nature and who nurtures us all.

  VLAD:

  For my strong-willed father, who always finishes what he starts.

  For my self-sacrificing mother, who prefers that

  I not refer to people as animals.

  For my nurturing wife, who liked the bit about

  diamond-encrusted grillz.

  For my curious children, who are confused about why

  daddy’s name is next to a picture of an ape.

  BUT WAIT, THAT’S NOT ALL!

  DOUG AND VLAD:

  For Bob Cialdini, our mentor and guru.

  Contents

  Introduction:Cadillacs, Communists, and Pink Bubble Gum

  Why did Elvis gold-plate the hubcaps on his Cadillac?

  1:Rationality, Irrationality, and the Dead Kennedys

  What do testosterone-crazed skateboarders have in common with Wall Street bankers?

  2:The Seven Subselves

  Did Martin Luther King Jr. have a multiple personality disorder? Do you?

  3:Home Economics Versus Wall Street Economics

  Why did Walt Disney play by different rules than his successors?

  4:Smoke Detectors in the Mind

  Why is it dangerous to seek the truth?

  5:Modern Cavemen

  How can illiterate jungle dwellers pass a test that tricks Harvard philosophers?

  6:Living Fast and Dying Young

  Why do people who go from rags to riches often end up in bankruptcy court?

  7:Gold Porsches and Green Peacocks

  Do people buy a gold Porsche and a green Toyota Prius for the same reason?

  8:Sexual Economics: His and Hers

  When is a gain for the goose a loss for the gander?

  9:Deep Rationality Parasites

  How do snake oil salesmen exploit deep rationality?

  Conclusion:Mementos from Our Tour

  What’s in it for moi?

  Acknowledgments

  Notes

  References

  Index

  Introduction

  Cadillacs, Communists, and Pink Bubble Gum

  It has been said that man is a rational animal. All my life

  I have been searching for evidence which could support this.

  —BERTRAND RUSSELL

  ARE YOUR DECISIONS rational or irrational?

  Let’s begin with a few quick questions. Would you do any of the following:

  •You’re a young fellow with some rhythm who grew up poor in Mississippi. Would you spend $785,400 on a Cadillac with gold-plated hubcaps and forty coats of paint custom-made from pearls, oriental fish scales, and diamond dust?

  •You’re a British woman living as an unemployed single mother. You’ve been writing in your spare time, though, and your books have begun to sell like wildfire. Would you give away your hard-earned money?

  •You’re an immigrant from a poor Communist country, where you once stood in line for four hours to buy your first banana. Just after you first land in America on a Pan Am jumbo jet, you are taken to a giant supermarket full of unimaginably delicious and nutritious goods. If your rich American relative offered you the opportunity to choose any one item to buy, would you purchase a pack of bubble gum?

  •You’re a college professor who has carefully protected his paltry retirement savings by putting them into safe bond accounts. You have watched the stock market running up wildly for several years, and there are rumors among financial experts that the bubble is about to burst. Would you choose that exact moment to take half of your already scarce retirement nest egg and put it into risky stocks?

  •You’re a wealthy Indian man in the state of Patiala with the legal right to marry as many women as you like. You have ninety wives already. Would you say enough is enough, or would you instead start looking for bride number ninety-one?

  •You’re a New Yorker working long hours as superintendent of an apartment building on East Eighty-sixth Street in Manhattan. Would you spend all of your savings on lottery tickets?

  If you didn’t answer yes to these questions, meet the folks who did:

  •Elvis Presley, the King of Rock ‘n’ Roll, who didn’t just buy the gaudiest Cadillac of all time but purchased over one hundred of them.

  •J. K. Rowling, author of the Harry Potter books, who gave away much of her hard-earned money, including writing one check for $15 million.

  •Vlad Griskevicius (one author of the book you now hold in your hands), whose first decision as a newly minted capitalist was to buy a pack of Bubblicious pink watermelon bubble gum. And as for that banana he stood in line for four hours to buy back in the old country, he ate it with the peel still on, thinking it would be downright stupid to throw away any part of so desirable a delicacy.

  •Doug Kenrick (the other author of the book in your hands), who, after watching his own retirement account grow sluggishly while the stock market shot up, transferred a large portion of those funds into the stock market in 2001, just in time to participate in a couple of historically unprecedented crashes in stock values. Unless this book makes the New York Times best seller’s list, he’s now planning to retire some time after his seventy-ninth birthday, probably to a small hut in rural Ecuador.

  •Rajinder Singh, Sixth Maharajah of the Indian state of Patiala, who not only married a ninety-first wife, but didn’t stop saying “I do” until he hit bride number 365.

  •New York building superintendent Ray Otero, who not only squandered his savings, but continues to spend $30,000 a year on lottery tickets—without hitting a big win yet.

  Some of these decisions, involving g
old-plated hubcaps, $15 million donations, ninety-first wives, and $30,000 lottery budgets, might seem disconnected from normal people’s everyday decisions, which are more likely to involve whether to dine at Taco Bell or Pizza Hut. Yet the decisions made by the King of Rock ’n’ Roll and the Maharajah of Patiala actually have a lot in common with those we all make every day. Even seemingly absurd choices often mask deeper questions of profound significance about how people make decisions.

  THE RATIONAL ANIMAL

  Lurking behind those seemingly silly decisions about Bubblicious bubble gum, bags of lottery tickets, and diamond-dusted Cadillacs is a profoundly important question. It is a question philosophers have pondered for centuries, and one that is central to economics, psychology, and our daily lives: What are the underlying reasons for people’s choices?

  Great thinkers from Aristotle and Descartes to Bertrand Russell and Oscar Wilde have all debated whether people are “rational animals.” Philosophers, scientists, and pundits alike have focused on one side of the coin, vigorously arguing whether humans are or are not “rational.” But the controversy has mostly overlooked the other side of the coin—the “animal” within the so-called rational animal. This book is about that creature.

  In the great debate about whether human decisions are rational or irrational, economists and psychologists have been obsessed over the surface features of our decisions—whether a person’s particular choice in a particular situation achieves that person’s goal. For example, does the decision to buy a $2 lottery ticket or a shiny new car make a person richer or happier? But to fully understand our decisions, we must dig below the surface and connect our present choices to the evolutionary past. To understand how people make decisions, we ask a fundamental question neglected by traditional views: Why did the brain evolve to make the choices that it does?

  Asking this question transforms the way we think about human decisions. New scientific findings are revealing that our decision making, rather than being either rational or irrational, is characterized by deep rationality. Our choices today reflect a deep-seated evolutionary wisdom, honed by our ancestors’ past successes and failures. This book explores how the choices made in the modern world—by you, me, and Elvis Presley—are rooted in a finely orchestrated set of ancestral mechanisms that often operate outside our conscious awareness.

  THIS NEW way of thinking is based on two insights at the center of this book:

  Insight 1: Human decision making serves evolutionary goals.

  The traditional way of thinking about human behavior is based almost completely on a consideration of people’s surface goals—getting a decent bargain on a pair of dress shoes, for example, or picking a fine restaurant for a date next Saturday. But humans, like all animals, evolved to make choices in ways that promote deeper evolutionary purposes. Once we start looking at modern choices through this ancestral lens, many decisions that appear foolish and irrational at the surface level turn out to be smart and adaptive at a deeper evolutionary level.

  Insight 2: Human decision making is designed to achieve several very different evolutionary goals.

  Economists and psychologists have often assumed that humans seek a single broad goal: to feel good or to maximize benefits. In actuality, all humans pursue several very different evolutionary goals, such as acquiring a mate, protecting themselves from danger, and attaining status. This is an important distinction. Depending on which evolutionary goal they currently have in mind, consciously or subconsciously, people will have very different biases and make very different choices.

  These deceptively simple insights represent a profound departure from earlier views of decision making. They imply that our choices, like those made by Elvis Presley and Maharajah Rajinder Singh, are often subconsciously guided by deeper evolutionary goals. And they suggest something even more radical: that there’s more than one you making decisions. Although it feels as if there is just one single self inside your head, your mind actually contains several different subselves, each with a specific evolutionary goal and a completely different set of priorities. You make decisions differently when your goal is wooing an attractive mate versus fending off the bad guys or climbing upward in the local status hierarchy. Although the divided nature of your mind often leads you to appear inconsistent and irrational, many of your choices are, at a deeper evolutionary level, even more rational than the great philosophers ever imagined.

  A ROUGH MAP OF THE TERRITORY

  In the pages ahead we journey into the depths of the ancestral mind. Each chapter begins with a visit to a mysterious corner of human decision making. Why do three out of four professional football players go bankrupt? How did such a large group of otherwise shrewd and intelligent investors allow Bernard Madoff to swindle them out of millions and millions of dollars? To solve each puzzle, we go beneath the surface and look at the newest scientific findings, letting you peek under the hood to examine the evidence for yourself. Along the way, you’ll discover the intimate connections between ovulating strippers, Wall Street financiers, testosterone-crazed skateboarders, Elvis Presley, and you.

  Here’s how our behind-the-scenes tour is organized. In Chapter 1 (“Rationality, Irrationality, and the Dead Kennedys”), we introduce the idea of deep rationality by comparing an eminently rational man, Joseph Patrick Kennedy, with his famously irrational descendants. In Chapter 2 (“The Seven Subselves”), we more properly introduce you to your subselves and consider whether you and Martin Luther King Jr. are hypocrites or just victims of a common form of multiple personality disorder. In Chapter 3 (“Home Economics Versus Wall Street Economics”), we examine how each subself negotiates with other people, exploring some nasty problems that arose when the Walt Disney Company stopped being a family business.

  In Chapter 4 (“Smoke Detectors in the Mind”), we take a closer look at the biases and mistakes each of your subselves is prone to make, and try to understand why the people in one African nation chose to starve rather than accept help. In Chapter 5 (“Modern Cavemen”), we investigate how understanding our subselves can help us make better decisions, asking why uneducated members of tribes deep in the Amazon can solve logical problems that stump students at Harvard.

  In Chapter 6 (“Living Fast and Dying Young”), we examine how the subselves change across the lifespan and try to understand why many people who go from rags to riches later go bankrupt. In Chapter 7 (“Gold Porsches and Green Peacocks”), we ask whether people might buy a shiny gold Cadillac and a dull green Toyota Prius for some of the very same reasons, even if they’re not consciously aware of them. In Chapter 8 (“Sexual Economics: His and Hers”), we probe more deeply into the ways that men’s and women’s subselves differ and try to figure out why in some societies men pay several years’ income for the company of a woman, while in others a woman’s family pays an immense dowry to buy her the company of a man.

  In Chapter 9 (“Deep Rationality Parasites”), we explore the dark side of the story—how our otherwise deeply rational tendencies can open us up to exploitation by clever parasites in the modern world, many of whom are hiding behind respectable business suits and sincere smiles. Finally, we wave good-bye and send you off with a few colorful postcards, each inscribed with an important takeaway message from our journey to the decision-making centers of the mind.

  YOUR TOUR GUIDES

  Your tour guides will be Doug Kenrick and Vlad Griskevicius. In some ways, it’s amazing that the two of us ended up on the same boat. Doug grew up in a junkie-infested New York neighborhood and seemed destined to join his male relatives in the state prison at Sing Sing. Vlad was born in Lithuania when it was still part of the Soviet Union, in a region more likely to produce potato farmers than college professors. But Doug managed to avoid a life of crime and instead became an evolutionary psychologist who has conducted hundreds of scientific studies on topics ranging from sex and murder to love and altruism. Vlad slipped out from behind the Iron Curtain and, after delighting in the joys of watermelon-flavored b
ubble gum, went on to study economics and social psychology among the capitalists. He is now a professor of marketing, conducting research and teaching courses on consumer behavior, advertising, and decision making. The two of us shared a brilliant mentor, Bob Cialdini, and we’ve collaborated with a group of highly creative colleagues, many of whom have contributed greatly to the scientific revolution we describe in this book.

  Most of the findings we’ll describe have been reported in scientific journals, and a few of those discoveries have been reported more widely in the media. But the big picture, connecting our own colleagues’ research findings with work by other psychologists, economists, decision scientists, biologists, and anthropologists, has yet to be filled in. In this book, we try to paint that wider canvas in a colorful way, showing why an intimate familiarity with our inner rational animal matters to business leaders and working stiffs, to armchair economists and their real-world counterparts, to politicians and their constituents, to teachers and those of us who still have a lot to learn.

  1

  Rationality, Irrationality, and the Dead Kennedys

  JOSEPH PATRICK KENNEDY was a shining example of a rational economic man. At age twenty-five, he became America’s youngest bank president, bragging to a newspaper reporter, “I want to be a millionaire by the age of thirty-five.” That was quite an aspiration in 1915, when the average yearly income was barely $1,000, and a loaf of bread cost nine cents. Kennedy made good on his lofty goal, though, becoming a Wall Street trader and turning a profit of $650,000 on a single transaction in 1922. Kennedy’s good fortunes continued even when the stock market took its infamous nosedive (he had sold off his holdings just in time). His impeccable sense of timing struck again in 1933, when he arranged a lucrative contract with Dewar’s to import liquor into the United States—just as Prohibition was about to end. And as the Hollywood movie industry was hitting the big time, he co-founded RKO pictures, with assets of over $80 million.