The Power of Habit is a work of nonfiction. Nonetheless, some names and personal characteristics of individuals or events have been changed in order to disguise identities. Any resulting resemblance to persons living or dead is entirely coincidental and unintentional.
Copyright © 2012 by Charles Duhigg
All rights reserved.
Published in the United States by Random House, an imprint of
The Random House Publishing Group, a division of Random House, Inc., New York.
RANDOM HOUSE and colophon are registered trademarks of Random House, Inc.
Library of Congress Cataloging-in-Publication Data
Duhigg, Charles.
The power of habit : why we do what we do in life and business / by Charles Duhigg.
p. cm.
Includes bibliographical references and index.
eISBN: 978-0-679-60385-6
1. Habit. 2. Habit—Social aspects. 3. Change (Psychology) I. Title.
BF335.D76 2012
158.1—dc23 2011029545
Illustration on this page by Andrew Pole
All other illustrations by Anton Ioukhnovets
www.atrandom.com
v3.1
CONTENTS
Cover
Title Page
Copyright
Dedication
PROLOGUE
The Habit Cure
PART ONE
The Habits of Individuals
1. THE HABIT LOOP
How Habits Work
2. THE CRAVING BRAIN
How to Create New Habits
3. THE GOLDEN RULE OF HABIT CHANGE
Why Transformation Occurs
PART TWO
The Habits of Successful Organizations
4. KEYSTONE HABITS, OR THE BALLAD OF PAUL O’NEILL
Which Habits Matter Most
5. STARBUCKS AND THE HABIT OF SUCCESS
When Willpower Becomes Automatic
6. THE POWER OF A CRISIS
How Leaders Create Habits Through Accident
and Design
7. HOW TARGET KNOWS WHAT YOU WANT BEFORE YOU DO
When Companies Predict (and Manipulate) Habits
PART THREE
The Habits of Societies
8. SADDLEBACK CHURCH AND THE MONTGOMERY BUS BOYCOTT
How Movements Happen
9. THE NEUROLOGY OF FREE WILL
Are We Responsible for Our Habits?
APPENDIX
A Reader’s Guide to Using These Ideas
Acknowledgments
A Note on Sources
Notes
PROLOGUE
The Habit Cure
She was the scientists’ favorite participant.
Lisa Allen, according to her file, was thirty-four years old, had started smoking and drinking when she was sixteen, and had struggled with obesity for most of her life. At one point, in her mid-twenties, collection agencies were hounding her to recover $10,000 in debts. An old résumé listed her longest job as lasting less than a year.
The woman in front of the researchers today, however, was lean and vibrant, with the toned legs of a runner. She looked a decade younger than the photos in her chart and like she could out-exercise anyone in the room. According to the most recent report in her file, Lisa had no outstanding debts, didn’t drink, and was in her thirty-ninth month at a graphic design firm.
“How long since your last cigarette?” one of the physicians asked, starting down the list of questions Lisa answered every time she came to this laboratory outside Bethesda, Maryland.
“Almost four years,” she said, “and I’ve lost sixty pounds and run a marathon since then.” She’d also started a master’s degree and bought a home. It had been an eventful stretch.
The scientists in the room included neurologists, psychologists, geneticists, and a sociologist. For the past three years, with funding from the National Institutes of Health, they had poked and prodded Lisa and more than two dozen other former smokers, chronic overeaters, problem drinkers, obsessive shoppers, and people with other destructive habits. All of the participants had one thing in common: They had remade their lives in relatively short periods of time. The researchers wanted to understand how. So they measured subjects’ vital signs, installed video cameras inside their homes to watch their daily routines, sequenced portions of their DNA, and, with technologies that allowed them to peer inside people’s skulls in real time, watched as blood and electrical impulses flowed through their brains while they were exposed to temptations such as cigarette smoke and lavish meals.prl.1 The researchers’ goal was to figure out how habits work on a neurological level—and what it took to make them change.
“I know you’ve told this story a dozen times,” the doctor said to Lisa, “but some of my colleagues have only heard it secondhand. Would you mind describing again how you gave up cigarettes?”
“Sure,” Lisa said. “It started in Cairo.” The vacation had been something of a rash decision, she explained. A few months earlier, her husband had come home from work and announced that he was leaving her because he was in love with another woman. It took Lisa a while to process the betrayal and absorb the fact that she was actually getting a divorce. There was a period of mourning, then a period of obsessively spying on him, following his new girlfriend around town, calling her after midnight and hanging up. Then there was the evening Lisa showed up at the girlfriend’s house, drunk, pounding on her door and screaming that she was going to burn the condo down.
“It wasn’t a great time for me,” Lisa said. “I had always wanted to see the pyramids, and my credit cards weren’t maxed out yet, so … ”
On her first morning in Cairo, Lisa woke at dawn to the sound of the call to prayer from a nearby mosque. It was pitch black inside her hotel room. Half blind and jet-lagged, she reached for a cigarette.
She was so disoriented that she didn’t realize—until she smelled burning plastic—that she was trying to light a pen, not a Marlboro. She had spent the past four months crying, binge eating, unable to sleep, and feeling ashamed, helpless, depressed, and angry, all at once. Lying in bed, she broke down. “It was like this wave of sadness,” she said. “I felt like everything I had ever wanted had crumbled. I couldn’t even smoke right.
“And then I started thinking about my ex-husband, and how hard it would be to find another job when I got back, and how much I was going to hate it and how unhealthy I felt all the time. I got up and knocked over a water jug and it shattered on the floor, and I started crying even harder. I felt desperate, like I had to change something, at least one thing I could control.”
She showered and left the hotel. As she rode through Cairo’s rutted streets in a taxi and then onto the dirt roads leading to the Sphinx, the pyramids of Giza, and the vast, endless desert around them, her self-pity, for a brief moment, gave way. She needed a goal in her life, she thought. Something to work toward.
So she decided, sitting in the taxi, that she would come back to Egypt and trek through the desert.
It was a crazy idea, Lisa knew. She was out of shape, overweight, with no money in the bank. She didn’t know the name of the desert she was looking at or if such a trip was possible. None of that mattered, though. She needed something to focus on. Lisa decided that she would give herself one year to prepare. And to survive such an expedition, she was certain she would have to make sacrifices.
In particular, she would need to quit smoking.
When Lisa finally made her way across the desert eleven months later—in an air-conditioned and motorized tour with a half-dozen other peo
ple, mind you—the caravan carried so much water, food, tents, maps, global positioning systems, and two-way radios that throwing in a carton of cigarettes wouldn’t have made much of a difference.
But in the taxi, Lisa didn’t know that. And to the scientists at the laboratory, the details of her trek weren’t relevant. Because for reasons they were just beginning to understand, that one small shift in Lisa’s perception that day in Cairo—the conviction that she had to give up smoking to accomplish her goal—had touched off a series of changes that would ultimately radiate out to every part of her life. Over the next six months, she would replace smoking with jogging, and that, in turn, changed how she ate, worked, slept, saved money, scheduled her workdays, planned for the future, and so on. She would start running half-marathons, and then a marathon, go back to school, buy a house, and get engaged. Eventually she was recruited into the scientists’ study, and when researchers began examining images of Lisa’s brain, they saw something remarkable: One set of neurological patterns—her old habits—had been overridden by new patterns. They could still see the neural activity of her old behaviors, but those impulses were crowded out by new urges. As Lisa’s habits changed, so had her brain.
It wasn’t the trip to Cairo that had caused the shift, scientists were convinced, or the divorce or desert trek. It was that Lisa had focused on changing just one habit—smoking—at first. Everyone in the study had gone through a similar process. By focusing on one pattern—what is known as a “keystone habit”—Lisa had taught herself how to reprogram the other routines in her life, as well.
It’s not just individuals who are capable of such shifts. When companies focus on changing habits, whole organizations can transform. Firms such as Procter & Gamble, Starbucks, Alcoa, and Target have seized on this insight to influence how work gets done, how employees communicate, and—without customers realizing it—the way people shop.
“I want to show you one of your most recent scans,” a researcher told Lisa near the end of her exam. He pulled up a picture on a computer screen that showed images from inside her head. “When you see food, these areas”—he pointed to a place near the center of her brain—“which are associated with craving and hunger, are still active. Your brain still produces the urges that made you overeat.
“However, there’s new activity in this area”—he pointed to the region closest to her forehead—“where we believe behavioral inhibition and self-discipline starts. That activity has become more pronounced each time you’ve come in.”
Lisa was the scientists’ favorite participant because her brain scans were so compelling, so useful in creating a map of where behavioral patterns—habits—reside within our minds. “You’re helping us understand how a decision becomes an automatic behavior,” the doctor told her.
Everyone in the room felt like they were on the brink of something important. And they were.
When you woke up this morning, what did you do first? Did you hop in the shower, check your email, or grab a doughnut from the kitchen counter? Did you brush your teeth before or after you toweled off? Tie the left or right shoe first? What did you say to your kids on your way out the door? Which route did you drive to work? When you got to your desk, did you deal with email, chat with a colleague, or jump into writing a memo? Salad or hamburger for lunch? When you got home, did you put on your sneakers and go for a run, or pour yourself a drink and eat dinner in front of the TV?
“All our life, so far as it has definite form, is but a mass of habits,” William James wrote in 1892.prl.2 Most of the choices we make each day may feel like the products of well-considered decision making, but they’re not. They’re habits. And though each habit means relatively little on its own, over time, the meals we order, what we say to our kids each night, whether we save or spend, how often we exercise, and the way we organize our thoughts and work routines have enormous impacts on our health, productivity, financial security, and happiness. One paper published by a Duke University researcher in 2006 found that more than 40 percent of the actions people performed each day weren’t actual decisions, but habits.prl.3
William James—like countless others, from Aristotle to Oprah—spent much of his life trying to understand why habits exist. But only in the past two decades have scientists and marketers really begun understanding how habits work—and more important, how they change.
This book is divided into three parts. The first section focuses on how habits emerge within individual lives. It explores the neurology of habit formation, how to build new habits and change old ones, and the methods, for instance, that one ad man used to push toothbrushing from an obscure practice into a national obsession. It shows how Procter & Gamble turned a spray named Febreze into a billion-dollar business by taking advantage of consumers’ habitual urges, how Alcoholics Anonymous reforms lives by attacking habits at the core of addiction, and how coach Tony Dungy reversed the fortunes of the worst team in the National Football League by focusing on his players’ automatic reactions to subtle on-field cues.
The second part examines the habits of successful companies and organizations. It details how an executive named Paul O’Neill—before he became treasury secretary—remade a struggling aluminum manufacturer into the top performer in the Dow Jones Industrial Average by focusing on one keystone habit, and how Starbucks turned a high school dropout into a top manager by instilling habits designed to strengthen his willpower. It describes why even the most talented surgeons can make catastrophic mistakes when a hospital’s organizational habits go awry.
The third part looks at the habits of societies. It recounts how Martin Luther King, Jr., and the civil rights movement succeeded, in part, by changing the ingrained social habits of Montgomery, Alabama—and why a similar focus helped a young pastor named Rick Warren build the nation’s largest church in Saddleback Valley, California. Finally, it explores thorny ethical questions, such as whether a murderer in Britain should go free if he can convincingly argue that his habits led him to kill.
Each chapter revolves around a central argument: Habits can be changed, if we understand how they work.
This book draws on hundreds of academic studies, interviews with more than three hundred scientists and executives, and research conducted at dozens of companies. (For an index of resources, please see the book’s notes and http://www.thepowerofhabit.com.) It focuses on habits as they are technically defined: the choices that all of us deliberately make at some point, and then stop thinking about but continue doing, often every day. At one point, we all consciously decided how much to eat and what to focus on when we got to the office, how often to have a drink or when to go for a jog. Then we stopped making a choice, and the behavior became automatic. It’s a natural consequence of our neurology. And by understanding how it happens, you can rebuild those patterns in whichever way you choose.
I first became interested in the science of habits eight years ago, as a newspaper reporter in Baghdad. The U.S. military, it occurred to me as I watched it in action, is one of the biggest habit-formation experiments in history.prl.4 Basic training teaches soldiers carefully designed habits for how to shoot, think, and communicate under fire. On the battlefield, every command that’s issued draws on behaviors practiced to the point of automation. The entire organization relies on endlessly rehearsed routines for building bases, setting strategic priorities, and deciding how to respond to attacks. In those early days of the war, when the insurgency was spreading and death tolls were mounting, commanders were looking for habits they could instill among soldiers and Iraqis that might create a durable peace.
I had been in Iraq for about two months when I heard about an officer conducting an impromptu habit modification program in Kufa, a small city ninety miles south of the capital. He was an army major who had analyzed videotapes of recent riots and had identified a pattern: Violence was usually preceded by a crowd of Iraqis gathering in a plaza or other open space and, over the course of several hours, growing in size. Food vendors would show up, as
well as spectators. Then, someone would throw a rock or a bottle and all hell would break loose.
When the major met with Kufa’s mayor, he made an odd request: Could they keep food vendors out of the plazas? Sure, the mayor said. A few weeks later, a small crowd gathered near the Masjid al-Kufa, or Great Mosque of Kufa. Throughout the afternoon, it grew in size. Some people started chanting angry slogans. Iraqi police, sensing trouble, radioed the base and asked U.S. troops to stand by. At dusk, the crowd started getting restless and hungry. People looked for the kebab sellers normally filling the plaza, but there were none to be found. The spectators left. The chanters became dispirited. By 8 P.M., everyone was gone.
When I visited the base near Kufa, I talked to the major. You wouldn’t necessarily think about a crowd’s dynamics in terms of habits, he told me. But he had spent his entire career getting drilled in the psychology of habit formation.
At boot camp, he had absorbed habits for loading his weapon, falling asleep in a war zone, maintaining focus amid the chaos of battle, and making decisions while exhausted and overwhelmed. He had attended classes that taught him habits for saving money, exercising each day, and communicating with bunkmates. As he moved up the ranks, he learned the importance of organizational habits in ensuring that subordinates could make decisions without constantly asking permission, and how the right routines made it easier to work alongside people he normally couldn’t stand. And now, as an impromptu nation builder, he was seeing how crowds and cultures abided by many of the same rules. In some sense, he said, a community was a giant collection of habits occurring among thousands of people that, depending on how they’re influenced, could result in violence or peace. In addition to removing the food vendors, he had launched dozens of different experiments in Kufa to influence residents’ habits. There hadn’t been a riot since he arrived.