The Power of Habit Summary (Review & Book Notes)

A great book that will teach you why you should focus on your habits (rather than the actions or outcomes), how to create and maintain them. All based on psychological studies. Highly recommended to anyone who wants a change in their life.

Authors: Charles Duhigg

Originally published: 2012

Pages: 400

Genre: Business

Goodreads rating: ⭐️ 4.13/5

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The Importance of Habits

All our life, so far as it has definite form, is but a mass of habits,” William James wrote in 1892: “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.”

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.

How Habits Form

This process—in which the brain converts a sequence of actions into an automatic routine—is known as “chunking,” and it’s at the root of how habits form.There are dozens—if not hundreds—of behavioral chunks that we rely on every day. Some are simple: You automatically put toothpaste on your toothbrush before sticking it in your mouth. Some, such as getting dressed or making the kids’ lunch, are a little more complex.

Habits, scientists say, emerge because the brain is constantly looking for ways to save effort. Left to its own devices, the brain will try to make almost any routine into a habit, because habits allow our minds to ramp down more often. This effort-saving instinct is a huge advantage. An efficient brain requires less room, which makes for a smaller head, which makes childbirth easier and therefore causes fewer infant and mother deaths. An efficient brain also allows us to stop thinking constantly about basic behaviors, such as walking and choosing what to eat, so we can devote mental energy to inventing spears, irrigation systems, and, eventually, airplanes and video games.

But conserving mental effort is tricky, because if our brains power down at the wrong moment, we might fail to notice something important, such as a predator hiding in the bushes or a speeding car as we pull onto the street. So our basal ganglia have devised a clever system to determine when to let habits take over. It’s something that happens whenever a chunk of behavior starts or ends.

To deal with this uncertainty, the brain spends a lot of effort at the beginning of a habit looking for something—a cue—that offers a hint as to which pattern to use.

This process within our brains is a three-step loop. First, there is a cue, a trigger that tells your brain to go into automatic mode and which habit to use. Then there is the routine, which can be physical or mental or emotional. Finally, there is a reward, which helps your brain figure out if this particular loop is worth remembering for the future.

Over time, this loop—cue, routine, reward; cue, routine, reward—becomes more and more automatic. The cue and reward become intertwined until a powerful sense of anticipation and craving emerges. Eventually, whether in a chilly MIT laboratory or your driveway, a habit is born.

Habits aren’t destiny. Habits can be ignored, changed, or replaced. But the reason the discovery of the habit loop is so important is that it reveals a basic truth: When a habit emerges, the brain stops fully participating in decision making. It stops working so hard, or diverts focus to other tasks. So unless you deliberately fight a habit—unless you find new routines—the pattern will unfold automatically.

However, simply understanding how habits work—learning the structure of the habit loop—makes them easier to control. Once you break a habit into its components, you can fiddle with the gears.

Habits never really disappear. They’re encoded into the structures of our brain, and that’s a huge advantage for us, because it would be awful if we had to relearn how to drive after every vacation. The problem is that your brain can’t tell the difference between bad and good habits, and so if you have a bad one, it’s always lurking there, waiting for the right cues and rewards.

Without habit loops, our brains would shut down, overwhelmed by the minutiae of daily life. People whose basal ganglia are damaged by injury or disease often become mentally paralyzed. They have trouble performing basic activities, such as opening a door or deciding what to eat. They lose the ability to ignore insignificant details.

The Power of Cues

Researchers have learned that cues can be almost anything, from a visual trigger such as a candy bar or a television commercial to a certain place, a time of day, an emotion, a sequence of thoughts, or the company of particular people. Routines can be incredibly complex or fantastically simple (some habits, such as those related to emotions, are measured in milliseconds). Rewards can range from food or drugs that cause physical sensations, to emotional payoffs, such as the feelings of pride that accompany praise or self-congratulation.

And in almost every experiment, researchers have seen echoes of Squire’s discoveries with Eugene: Habits are powerful, but delicate. They can emerge outside our consciousness, or can be deliberately designed. They often occur without our permission, but can be reshaped by fiddling with their parts. They shape our lives far more than we realize—they are so strong, in fact, that they cause our brains to cling to them at the exclusion of all else, including common sense.

Why Habits Are So Powerful

They create neurological cravings. Most of the time, these cravings emerge so gradually that we’re not really aware they exist, so we’re often blind to their influence. But as we associate cues with certain rewards, a subconscious craving emerges in our brains that starts the habit loop spinning.

“There is nothing programmed into our brains that makes us see a box of doughnuts and automatically want a sugary treat,” Schultz told me. “But once our brain learns that a doughnut box contains yummy sugar and other carbohydrates, it will start anticipating the sugar high. Our brains will push us toward the box. Then, if we don’t eat the doughnut, we’ll feel disappointed.”

This is how new habits are created: by putting together a cue, a routine, and a reward, and then cultivating a craving that drives the loop.

The Power of Cravings

To understand the power of cravings in creating habits, consider how exercise habits emerge. In 2002 researchers at New Mexico State University wanted to understand why people habitually exercise. They studied 266 individuals, most of whom worked out at least three times a week. What they found was that many of them had started running or lifting weights almost on a whim, or because they suddenly had free time or wanted to deal with unexpected stresses in their lives. However, the reason they continued—why it became a habit—was because of a specific reward they started to crave.

In one group, 92 percent of people said they habitually exercised because it made them “feel good”—they grew to expect and crave the endorphins and other neurochemicals a workout provided. In another group, 67 percent of people said that working out gave them a sense of “accomplishment”—they had come to crave a regular sense of triumph from tracking their performances, and that selfeward was enough to make the physical activity into a habit.

If you want to start running each morning, it’s essential that you choose a simple cue (like always lacing up your sneakers before breakfast or leaving your running clothes next to your bed) and a clear reward (such as a midday treat, a sense of accomplishment from recording your miles, or the endorphin rush you get from a jog). But countless studies have shown that a cue and a reward, on their own, aren’t enough for a new habit to last. Only when your brain starts expecting the reward—craving the endorphins or sense of accomplishment—will it become automatic to lace up your jogging shoes each morning. The cue, in addition to triggering a routine, must also trigger a craving for the reward to come.

Want to exercise more? Choose a cue, such as going to the gym as soon as you wake up, and a reward, such as a smoothie after each workout. Then think about that smoothie, or about the endorphin rush you’ll feel. Allow yourself to anticipate the reward. Eventually, that craving will make it easier to push through the gym doors every day.

Cravings are what drive habits. And figuring out how to spark a craving makes creating a new habit easier. It’s as true now as it was almost a century ago. Every night, millions of people scrub their teeth in order to get a tingling feeling; every morning, millions put on their jogging shoes to capture an endorphin rush they’ve learned to crave.

Today, habit reversal therapy is used to treat verbal and physical tics, depression, smoking, gambling problems, anxiety, bedwetting, procrastination, obsessive-compulsive disorders, and other behavioral problems. And its techniques lay bare one of the fundamental principles of habits: Often, we don’t really understand the cravings driving our behaviors until we look for them.

Changing Habits

Champions don’t do extraordinary things,” Dungy would explain. “They do ordinary things, but they do them without thinking, too fast for the other team to react. They follow the habits they’ve learned.

Dungy recognized that you can never truly extinguish bad habits.

Rather, to change a habit, you must keep the old cue, and deliver the old reward, but insert a new routine.

That’s the rule: If you use the same cue, and provide the same reward, you can shift the routine and change the habit. Almost any behavior can be transformed if the cue and reward stay the same

The Golden Rule of Habit Change

You Can’t Extinguish a Bad Habit, You Can Only Change It.

How Alcoholic Anonymous Succeeded

An estimated 2.1 million people seek help from AA each year, and as many as 10 million alcoholics may have achieved sobriety through the group.

All of which is somewhat unexpected, because AA has almost no grounding in science or most accepted therapeutic methods.

Alcoholism, of course, is more than a habit. It’s a physical addiction with psychological and perhaps genetic roots. What’s interesting about AA, however, is that the program doesn’t directly attack many of the psychiatric or biochemical issues that researchers say are often at the core of why alcoholics drink. In fact, AA’s methods seem to sidestep scientific and medical findings altogether, as well as the types of intervention many psychiatrists say alcoholics really need.

What AA provides instead is a method for attacking the habits that surround alcohol use. AA, in essence, is a giant machine for changing habit loops.

Researchers say that AA works because the program forces people to identify the cues and rewards that encourage their alcoholic habits, and then helps them find new behaviors. But to change an old habit, you must address an old craving. You have to keep the same cues and rewards as before, and feed the craving by inserting a new routine.

Then, AA asks alcoholics to search for the rewards they get from alcohol. What cravings, the program asks, are driving your habit loop? Often, intoxication itself doesn’t make the list. Alcoholics crave a drink because it offers escape, relaxation, companionship, the blunting of anxieties, and an opportunity for emotional release. They might crave a cocktail to forget their worries. But they don’t necessarily crave feeling drunk. The physical effects of alcohol are often one of the least rewarding parts of drinking for addicts.

AA forces you to create new routines for what to do each night instead of drinking,” said Tonigan. “You can relax and talk through your anxieties at the meetings. The triggers and payoffs stay the same, it’s just the behavior that changes.

The first cracks in the theory that Alcoholics Anonymous succeeded solely by reprogramming participants’ habits started appearing a little over a decade ago and were caused by stories from alcoholics like John. Researchers began finding that habit replacement worked pretty well for many people until the stresses of life—such as finding out your mom has cancer, or your marriage is coming apart—got too high, at which point alcoholics often fell off the wagon. Academics asked why, if habit replacement is so effective, it seemed to fail at such critical moments. And as they dug into alcoholics’ stories to answer that question, they learned that replacement habits only become durable new behaviors when they are accompanied by something else.

The secret, the alcoholics said, was God.

Alcoholics who practiced the techniques of habit replacement, the data indicated, could often stay sober until there was a stressful event in their lives—at which point, a certain number started drinking again, no matter how many new routines they had embraced.

However, those alcoholics who believed, like John in Brooklyn, that some higher power had entered their lives were more likely to make it through the stressful periods with their sobriety intact.

It wasn’t God that mattered, the researchers figured out. It was belief itself that made a difference. Once people learned how to believe in something, that skill started spilling over to other parts of their lives, until they started believing they could change. Belief was the ingredient that made a reworked habit loop into a permanent behavior.

“I wouldn’t have said this a year ago—that’s how fast our understanding is changing,” said Tonigan, the University of New Mexico researcher, “but belief seems critical. You don’t have to believe in God, but you do need the capacity to believe that things will get better.

“Even if you give people better habits, it doesn’t repair why they started drinking in the first place. Eventually they’ll have a bad day, and no new routine is going to make everything seem okay. What can make a difference is believing that they can cope with that stress without alcohol.

Belief is easier when it occurs within a community.

How Do Habits Change?

There is, unfortunately, no specific set of steps guaranteed to work for every person. We know that a habit cannot be eradicated—it must, instead, be replaced. And we know that habits are most malleable when the Golden Rule of habit change is applied: If we keep the same cue and the same reward, a new routine can be inserted.

But that’s not enough. For a habit to stay changed, people must believe change is possible. And most often, that belief only emerges with the help of a group.

If you want to quit smoking, figure out a different routine that will satisfy the cravings filled by cigarettes. Then, find a support group, a collection of other former smokers, or a community that will help you believe you can stay away from nicotine, and use that group when you feel you might stumble.

If you want to lose weight, study your habits to determine why you really leave your desk for a snack each day, and then find someone else to take a walk with you, to gossip with at their desk rather than in the cafeteria, a group that tracks weight-loss goals together, or someone who also wants to keep a stock of apples, rather than chips, nearby.

The evidence is clear: If you want to change a habit, you must find an alternative routine, and your odds of success go up dramatically when you commit to changing as part of a group. Belief is essential, and it grows out of a communal experience, even if that community is only as large as two people.

Keystone Habits

O’Neill believed that some habits have the power to start a chain reaction, changing other habits as they move through an organization. Some habits, in other words, matter more than others in remaking businesses and lives. These are “keystone habits,” and they can influence how people work, eat, play, live, spend, and communicate. Keystone habits start a process that, over time, transforms everything.

Keystone habits say that success doesn’t depend on getting every single thing right, but instead relies on identifying a few key priorities and fashioning them into powerful levers.

The habits that matter most are the ones that, when they start to shift, dislodge and remake other patterns.

Keystone habits explain how Michael Phelps became an Olympic champion and why some college students outperform their peers. They describe why some people, after years of trying, suddenly lose forty pounds while becoming more productive at work and still getting home in time for dinner with their kids.

The Importance of Organizational Habits

Researchers have found institutional habits in almost every organization or company they’ve scrutinized. “Individuals have habits; groups have routines,” wrote the academic Geoffrey Hodgson, who spent a career examining organizational patterns. “Routines are the organizational analogue of habits”.

How Keystone Habits Cause Widespread Shifts

When people start habitually exercising, even as infrequently as once a week, they start changing other, unrelated patterns in their lives, often unknowingly. Typically, people who exercise start eating better and becoming more productive at work. They smoke less and show more patience with colleagues and family. They use their credit cards less frequently and say they feel less stressed. It’s not completely clear why. But for many people, exercise is a keystone habit that triggers widespread change. “Exercise spills over,” said James Prochaska, a University of Rhode Island researcher. “There’s something about it that makes other good habits easier.”

Studies have documented that families who habitually eat dinner together seem to raise children with better homework skills, higher grades, greater emotional control, and more confidence. Making your bed every morning is correlated with better productivity, a greater sense of well-being, and stronger skills at sticking with a budget.

If you focus on changing or cultivating keystone habits, you can cause widespread shifts. However, identifying keystone habits is tricky. To find them, you have to know where to look. Detecting keystone habits means searching out certain characteristics. Keystone habits offer what is known within academic literature as “small wins.” They help other habits to flourish by creating new structures, and they establish cultures where change becomes contagious.

Small wins are exactly what they sound like, and are part of how keystone habits create widespread changes. A huge body of research has shown that small wins have enormous power, an influence disproportionate to the accomplishments of the victories themselves. “Small wins are a steady application of a small advantage,” one Cornell professor wrote in 1984. “Once a small win has been accomplished, forces are set in motion that favor another small win.” Small wins fuel transformative changes by leveraging tiny advantages into patterns that convince people that bigger achievements are within reach.

“Small wins do not combine in a neat, linear, serial form, with each step being a demonstrable step closer to some predetermined goal,” wrote Karl Weick, a prominent organizational psychologist. “More common is the circumstance where small wins are scattered … like miniature experiments that test implicit theories about resistance and opportunity and uncover both resources and barriers that were invisible before the situation was stirred up.”

Keystone habits make tough choices—such as firing a top executive—easier, because when that person violates the culture, it’s clear they have to go. Sometimes these cultures manifest themselves in special vocabularies, the use of which becomes, itself, a habit that defines an organization. At Alcoa, for instance, there were “Core Programs” and “Safety Philosophies,” phrases that acted like suitcases, containing whole conversations about priorities, goals, and ways of thinking.

Cultures grow out of the keystone habits in every organization, whether leaders are aware of them or not.

The Importance of Willpower

Dozens of studies show that willpower is the single most important keystone habit for individual success.

The best way to strengthen willpower and give students a leg up, studies indicate, is to make it into a habit. “Sometimes it looks like people with great self-control aren’t working hard—but that’s because they’ve made it automatic,” Angela Duckworth, one of the University of Pennsylvania researchers told me. “Their willpower occurs without them having to think about it.”

“If you want to do something that requires willpower—like going for a run after work—you have to conserve your willpower muscle during the day,” Muraven told me. “If you use it up too early on tedious tasks like writing emails or filling out complicated and boring expense forms, all the strength will be gone by the time you get home.”

“When you learn to force yourself to go to the gym or start your homework or eat a salad instead of a hamburger, part of what’s happening is that you’re changing how you think,” said Todd Heatherton, a researcher at Dartmouth who has worked on willpower studies. “People get better at regulating their impulses. They learn how to distract themselves from temptations. And once you’ve gotten into that willpower groove, your brain is practiced at helping you focus on a goal.”

“That’s why signing kids up for piano lessons or sports is so important. It has nothing to do with creating a good musician or a five-year-old soccer star,” said Heatherton. “When you learn to force yourself to practice for an hour or run fifteen laps, you start building selfegulatory strength. A five-year-old who can follow the ball for ten minutes becomes a sixth grader who can start his homework on time.”

How Willpower Becomes a Habit

This is how willpower becomes a habit: by choosing a certain behavior ahead of time, and then following that routine when an inflection point arrives. When the Scottish patients filled out their booklets, or Travis studied the LATTE method, they decided ahead of time how to react to a cue—a painful muscle or an angry customer. When the cue arrived, the routine occurred.

“We’ve found this again and again,” Muraven told me. “When people are asked to do something that takes self-control, if they think they are doing it for personal reasons—if they feel like it’s a choice or something they enjoy because it helps someone else—it’s much less taxing. If they feel like they have no autonomy, if they’re just following orders, their willpower muscles get tired much faster. In both cases, people ignored the cookies. But when the students were treated like cogs, rather than people, it took a lot more willpower.”

For companies and organizations, this insight has enormous implications. Simply giving employees a sense of agency—a feeling that they are in control, that they have genuine decision-making authority—can radically increase how much energy and focus they bring to their jobs.

How Organizational Habits Work

When An Evolutionary Theory of Economic Change was first published in 1982, very few people outside of academia noticed.

The authors, Yale professors Richard Nelson and Sidney Winter, were best known for a series of intensely analytic papers exploring Schumpeterian theory that even most PhD candidates didn’t pretend to understand.

Within the world of business strategy and organizational theory, however, the book went off like a bombshell. It was soon hailed as one of the most important texts of the century.

“Nelson and Winter had spent more than a decade examining how companies work, trudging through swamps of data before arriving at their central conclusion: “Much of firm behavior,” they wrote, is best “understood as a reflection of general habits and strategic orientations coming from the firm’s past,” rather than “the result of a detailed survey of the remote twigs of the decision tree.”

Or, put in language that people use outside of theoretical economics, it may seem like most organizations make rational choices based on deliberate decision making, but that’s not really how companies operate at all. Instead, firms are guided by long-held organizational habits, patterns that often emerge from thousands of employees’ independent decisions. And these habits have more profound impacts than anyone previously understood.

These organizational habits—or “routines,” as Nelson and Winter called them—are enormously important, because without them, most companies would never get any work done. Routines provide the hundreds of unwritten rules that companies need to operate. They allow workers to experiment with new ideas without having to ask for permission at every step. They provide a kind of “organizational memory,” so that managers don’t have to reinvent the sales process every six months or panic each time a VP quits. Routines reduce uncertainty.

But among the most important benefits of routines is that they create truces between potentially warring groups or individuals within an organization.

Most economists are accustomed to treating companies as idyllic places where everyone is devoted to a common goal: making as much money as possible. Nelson and Winter pointed out that, in the real world, that’s not how things work at all. Companies aren’t big happy families where everyone plays together nicely. Rather, most workplaces are made up of fiefdoms where executives compete for power and credit, often in hidden skirmishes that make their own performances appear superior and their rivals’ seem worse. Divisions compete for resources and sabotage each other to steal glory. Bosses pit their subordinates against one another so that no one can mount a coup.

Companies aren’t families. They’re battlefields in a civil war.

Yet despite this capacity for internecine warfare, most companies roll along relatively peacefully, year after year, because they have routines—habits—that create truces that allow everyone to set aside their rivalries long enough to get a day’s work done.

Organizational habits offer a basic promise: If you follow the established patterns and abide by the truce, then rivalries won’t destroy the company, the profits will roll in, and, eventually, everyone will get rich.

“Routines and truces offer a type of rough organizational justice, and because of them, Nelson and Winter wrote, conflict within companies usually “follows largely predictable paths and stays within predictable bounds that are consistent with the ongoing routine.… The usual amount of work gets done, reprimands and compliments are delivered with the usual frequency.… Nobody is trying to steer the organizational ship into a sharp turn in the hope of throwing a rival overboard.”

Most of the time, routines and truces work perfectly. Rivalries still exist, of course, but because of institutional habits, they’re kept within bounds and the business thrives.

Creating successful organizations isn’t just a matter of balancing authority. For an organization to work, leaders must cultivate habits that both create a real and balanced peace and, paradoxically, make it absolutely clear who’s in charge.

A company with dysfunctional habits can’t turn around simply because a leader orders it. Rather, wise executives seek out moments of crisis—or create the perception of crisis—and cultivate the sense that something must change, until everyone is finally ready to overhaul the patterns they live with each day.

How Habits Are Affected by Life Changes

People’s buying habits are more likely to change when they go through a major life event. When someone gets married, for example, they’re more likely to start buying a new type of coffee. When they move into a new house, they’re more apt to purchase a different kind of cereal. When they get divorced, there’s a higher chance they’ll start buying different brands of beer. Consumers going through major life events often don’t notice, or care, that their shopping patterns have shifted.

And what’s the biggest life event for most people? What causes the greatest disruption and “vulnerability to marketing interventions”? Having a baby. There’s almost no greater upheaval for most customers than the arrival of a child. As a result, new parents’ habits are more flexible at that moment than at almost any other period in an adult’s life.

So for companies, pregnant women are gold mines.

How to Market New Habits Using Old Ones

“Sometimes stations will do research by calling listeners on the phone, and play a snippet of a song, and listeners will say, ‘I’ve heard that a million times. I’m totally tired of it,’ ” Meyer told me. “But when it comes on the radio, your subconscious says, ‘I know this song! I’ve heard it a million times! I can sing along!’ Sticky songs are what you expect to hear on the radio. Your brain secretly wants that song, because it’s so familiar to everything else you’ve already heard and liked. It just sounds right.”

Our brains crave familiarity in music because familiarity is how we manage to hear without becoming distracted by all the sound.

That’s why songs that sound “familiar”—even if you’ve never heard them before—are sticky. Our brains are designed to prefer auditory patterns that seem similar to what we’ve already heard. When Celine Dion releases a new song—and it sounds like every other song she’s sung, as well as most of the other songs on the radio—our brains unconsciously crave its recognizability and the song becomes sticky. You might never attend a Celine Dion concert, but you’ll listen to her songs on the radio, because that’s what you expect to hear as you drive to work. Those songs correspond perfectly to your habits.

Much of the time, we don’t actually choose if we like or dislike a song. It would take too much mental effort. Instead, we react to the cues (“This sounds like all the other songs I’ve ever liked”) and rewards (“It’s fun to hum along!”) and without thinking, we either start singing, or reach over and change the station.

Whether selling a new song, a new food, or a new crib, the lesson is the same: If you dress a new something in old habits, it’s easier for the public to accept it.

Someday soon, say predictive analytics experts, it will be possible for companies to know our tastes and predict our habits better than we know ourselves. However, knowing that someone might prefer a certain brand of peanut butter isn’t enough to get them to act on that preference. To market a new habit—be it groceries or aerobics—you must understand how to make the novel seem familiar.

The Power of Social Habits

Social habits are what fill streets with protesters who may not know one another, who might be marching for different reasons, but who are all moving in the same direction. Social habits are why some initiatives become world-changing movements, while others fail to ignite. And the reason why social habits have such influence is because at the root of many movements—be they large-scale revolutions or simple fluctuations in the churches people attend—is a three-part process that historians and sociologists say shows up again and again.

A movement starts because of the social habits of friendship and the strong ties between close acquaintances.

It grows because of the habits of a community, and the weak ties that hold neighborhoods and clans together.

And it endures because a movement’s leaders give participants new habits that create a fresh sense of identity and a feeling of ownership.

Usually, only when all three parts of this process are fulfilled can a movement become self-propelling and reach a critical mass.

The Power of Weak Ties and Peer Pressure

In general, sociologists say, most of us have friends who are like us. We might have a few close acquaintances who are richer, a few who are poorer, and a few of different races—but, on the whole, our deepest relationships tend to be with people who look like us, earn about the same amount of money, and come from similar backgrounds.

There’s a natural instinct embedded in friendship, a sympathy that makes us willing to fight for someone we like when they are treated unjustly. Studies show that people have no problem ignoring strangers’ injuries, but when a friend is insulted, our sense of outrage is enough to overcome the inertia that usually makes protests hard to organize.

In the late 1960s, a Harvard PhD student named Mark Granovetter set out to answer that question by studying how 282 men had found their current employment. He tracked how they had learned about open positions, whom they had called for referrals, the methods they used to land interviews, and most important, who had provided a helping hand. As expected, he found that when job hunters approached strangers for assistance, they were rejected. When they appealed to friends, help was provided.

More surprising, however, was how often job hunters also received help from casual acquaintances—friends of friends—people who were neither strangers nor close pals. Granovetter called those connections “weak ties,” because they represented the links that connect people who have acquaintances in common, who share membership in social networks, but aren’t directly connected by the strong ties of friendship themselves.

In fact, in landing a job, Granovetter discovered, weak-tie acquaintances were often more important than strong-tie friends because weak ties give us access to social networks where we don’t otherwise belong. Many of the people Granovetter studied had learned about new job opportunities through weak ties, rather than from close friends, which makes sense because we talk to our closest friends all the time, or work alongside them or read the same blogs.

The power of weak ties helps explain how a protest can expand from a group of friends into a broad social movement. Convincing thousands of people to pursue the same goal—especially when that pursuit entails real hardship, such as walking to work rather than taking the bus, or going to jail, or even skipping a morning cup of coffee because the company that sells it doesn’t support organic farming—is hard. Most people don’t care enough about the latest outrage to give up their bus ride or caffeine unless it’s a close friend that has been insulted or jailed. So there is a tool that activists have long relied upon to compel protest, even when a group of people don’t necessarily want to participate. It’s a form of persuasion that has been remarkably effective over hundreds of years. It’s the sense of obligation that neighborhoods or communities place upon themselves.

In other words, peer pressure.

Peer pressure—and the social habits that encourage people to conform to group expectations—is difficult to describe, because it often differs in form and expression from person to person.

The habits of peer pressure, however, have something in common. They often spread through weak ties. And they gain their authority through communal expectations. If you ignore the social obligations of your neighborhood, if you shrug off the expected patterns of your community, you risk losing your social standing. You endanger your access to many of the social benefits that come from joining the country club, the alumni association, or the church in the first place.In other words, if you don’t give the caller looking for a job a helping hand, he might complain to his tennis partner, who might mention those grumblings to someone in the locker room who you were hoping to attract as a client, who is now less likely to return your call because you have a reputation for not being a team player. On a playground, peer pressure is dangerous. In adult life, it’s how business gets done and communities self-organize.

Such peer pressure, on its own, isn’t enough to sustain a movement. But when the strong ties of friendship and the weak ties of peer pressure merge, they create incredible momentum. That’s when widespread social change can begin.

Movements don’t emerge because everyone suddenly decides to face the same direction at once. They rely on social patterns that begin as the habits of friendship, grow through the habits of communities, and are sustained by new habits that change participants’ sense of self.

Sleepwalking, Sleep Terrors and Habits

Sleepwalking is an odd outgrowth of a normal aspect of how our brains work while we slumber. Most of the time, as our bodies move in and out of different phases of rest, our most primitive neurological structure—the brain stem—paralyzes our limbs and nervous system, allowing our brains to experience dreams without our bodies moving. Usually, people can make the transition in and out of paralysis multiple times each night without any problems. Within neurology, it’s known as the “switch.”

Some people’s brains, though, experience switching errors. They go into incomplete paralysis as they sleep, and their bodies are active while they dream or pass between sleep phases. This is the root cause of sleepwalking and for the majority of sufferers, it is an annoying but benign problem. Someone might dream about eating a cake, for instance, and the next morning find a ravaged box of doughnuts in the kitchen. Someone will dream about going to the bathroom, and later discover a wet spot in the hall. Sleepwalkers can behave in complex ways—for instance, they can open their eyes, see, move around, and drive a car or cook a meal—all while essentially unconscious, because the parts of their brain associated with seeing, walking, driving, and cooking can function while they are asleep without input from the brain’s more advanced regions, such as the prefrontal cortex. Sleepwalkers have been known to boil water and make tea. One operated a motorboat. Another turned on an electric saw and started feeding in pieces of wood before going back to bed. But in general, sleepwalkers will not do things that are dangerous to themselves or others. Even asleep, there’s an instinct to avoid peril.

However, as scientists have examined the brains of sleepwalkers, they’ve found a distinction between sleepwalking—in which people might leave their beds and start acting out their dreams or other mild impulses—and something called sleep terrors. When a sleep terror occurs, the activity inside people’s brains is markedly different from when they are awake, semi-conscious, or even sleepwalking. People in the midst of sleep terrors seem to be in the grip of terrible anxieties, but are not dreaming in the normal sense of the word. Their brains shut down except for the most primitive neurological regions, which include what are known as “central pattern generators.” These areas of the brain are the same ones studied by Dr. Larry Squire and the scientists at MIT, who found the neurological machinery of the habit loop. To a neurologist, in fact, a brain experiencing a sleep terror looks very similar to a brain following a habit.

The behaviors of people in the grip of sleep terrors are habits, though of the most primal kind. The “central pattern generators” at work during a sleep terror are where such behavioral patterns as walking, breathing, flinching from a loud noise, or fighting an attacker come from. We don’t usually think about these behaviors as habits, but that’s what they are: automatic behaviors so ingrained in our neurology that, studies show, they can occur with almost no input from the higher regions of the brain.

However, these habits, when they occur during sleep terrors, are different in one critical respect: Because sleep deactivates the prefrontal cortex and other high cognition areas, when a sleep terror habit is triggered, there is no possibility of conscious intervention. If the fight-or-flight habit is cued by a sleep terror, there is no chance that someone can override it through logic or reason.

When someone in the midst of a sleep terror starts feeling threatened or sexually aroused—two of the most common sleep terror experiences—they react by following the habits associated with those stimuli. People experiencing sleep terrors have jumped off of tall roofs because they believed they were fleeing from attackers. They have killed their own babies because, they believed, they were fighting wild animals. They have raped their spouses, even as their victims begged them to stop, because once the sleepers’ arousal began, they followed the ingrained habit to satisfy the urge. Sleepwalking seems to allow some choice, some participation by our higher brains that tell us to stay away from the edge of the roof. Someone in the grip of a sleep terror, however, simply follows the habit loop no matter where it leads.

How Habits Influence Our Lifes

Why does it seem the bereaved husband is a victim, while the bankrupt gambler got her just deserts? Why do some habits seem like they should be so easy to control, while others seem out of reach?

More important, is it right to make a distinction in the first place?

Habits are not as simple as they appear. Habits—even once they are rooted in our minds—aren’t destiny. We can choose our habits, once we know how. Everything we know about habits, from neurologists studying amnesiacs and organizational experts remaking companies, is that any of them can be changed, if you understand how they function.

Hundreds of habits influence our days—they guide how we get dressed in the morning, talk to our kids, and fall asleep at night; they impact what we eat for lunch, how we do business, and whether we exercise or have a beer after work. Each of them has a different cue and offers a unique reward. Some are simple and others are complex, drawing upon emotional triggers and offering subtle neurochemical prizes. But every habit, no matter its complexity, is malleable. The most addicted alcoholics can become sober. The most dysfunctional companies can transform themselves. A high school dropout can become a successful manager.

However, to modify a habit, you must decide to change it. You must consciously accept the hard work of identifying the cues and rewards that drive the habits’ routines, and find alternatives. You must know you have control and be self-conscious enough to use it.

Perhaps a sleepwalking murderer can plausibly argue he wasn’t aware of his habit, and so he doesn’t bear responsibility for his crime. But almost all the other patterns that exist in most people’s lives—how we eat and sleep and talk to our kids, how we unthinkingly spend our time, attention, and money—those are habits that we know exist. And once you understand that habits can change, you have the freedom—and the responsibility—to remake them. Once you understand that habits can be rebuilt, the power of habit becomes easier to grasp, and the only option left is to get to work.

If you believe you can change—if you make it a habit—the change becomes real. This is the real power of habit: the insight that your habits are what you choose them to be. Once that choice occurs—and becomes automatic—it’s not only real, it starts to seem inevitable, the thing, as James wrote, that bears “us irresistibly toward our destiny, whatever the latter may be.”

The way we habitually think of our surroundings and ourselves create the worlds that each of us inhabit. “There are these two young fish swimming along and they happen to meet an older fish swimming the other way, who nods at them and says ‘Morning, boys. How’s the water?’ ” the writer David Foster Wallace told a class of graduating college students in 2005. “And the two young fish swim on for a bit, and then eventually one of them looks over at the other and goes ‘What the hell is water?’ ”

The water is habits, the unthinking choices and invisible decisions that surround us every day—and which, just by looking at them, become visible again.

Summary

Change might not be fast and it isn’t always easy. But with time and effort, almost any habit can be reshaped.

The Framework:

Identify the routine
Experiment with rewards
Isolate the cue
Have a plan

Step One: Identify The Routine

The MIT researchers in chapter 1 discovered a simple neurological loop at the core of every habit, a loop that consists of three parts: a cue, a routine, and a reward.

To understand your own habits, you need to identify the components of your loops. Once you have diagnosed the habit loop of a particular behavior, you can look for ways to supplant old vices with new routines.

As an example, let’s say you have a bad habit, like I did when I started researching this book, of going to the cafeteria and buying a chocolate chip cookie every afternoon.

How do you start diagnosing and then changing this behavior? By figuring out the habit loop. And the first step is to identify the routine. In this cookie scenario—as with most habits—the routine is the most obvious aspect: It’s the behavior you want to change. Your routine is that you get up from your desk in the afternoon, walk to the cafeteria, buy a chocolate chip cookie, and eat it while chatting with friends.

“Next, some less obvious questions: What’s the cue for this routine? Is it hunger? Boredom? Low blood sugar? That you need a break before plunging into another task?

And what’s the reward? The cookie itself? The change of scenery? The temporary distraction? Socializing with colleagues? Or the burst of energy that comes from that blast of sugar?

To figure this out, you’ll need to do a little experimentation.

Step Two: Experiment with Rewards

Rewards are powerful because they satisfy cravings. But we’re often not conscious of the cravings that drive our behaviors. When the Febreze marketing team discovered that consumers desired a fresh scent at the end of a cleaning ritual, for example, they had found a craving that no one even knew existed. It was hiding in plain sight. Most cravings are like this: obvious in retrospect, but incredibly hard to see when we are under their sway.

To figure out which cravings are driving particular habits, it’s useful to experiment with different rewards. This might take a few days, or a week, or longer. During that period, you shouldn’t feel any pressure to make a real change—think of yourself as a scientist in the data collection stage.

On the first day of your experiment, when you feel the urge to go to the cafeteria and buy a cookie, adjust your routine so it delivers a different reward. For instance, instead of walking to the cafeteria, go outside, walk around the block, and then go back to your desk without eating anything. The next day, go to the cafeteria and buy a donut, or a candy bar, and eat it at your desk. The next day, go to the cafeteria, buy an apple, and eat it while chatting with your friends. Then, try a cup of coffee. Then, instead of going to the cafeteria, walk over to your friend’s office and gossip for a few minutes and go back to your desk.

You get the idea. What you choose to do instead of buying a cookie isn’t important. The point is to test different hypotheses to determine which craving is driving your routine. Are you craving the cookie itself, or a break from work? If it’s the cookie, is it because you’re hungry? (In which case the apple should work just as well.) Or is it because you want the burst of energy the cookie provides.

Or are you wandering up to the cafeteria as an excuse to socialize, and the cookie is just a convenient excuse? (If so, walking to someone’s desk and gossiping for a few minutes should satisfy the urge.)

As you test four or five different rewards, you can use an old trick to look for patterns: After each activity, jot down on a piece of paper the first three things that come to mind when you get back to your desk. They can be emotions, random thoughts, reflections on how you’re feeling, or just the first three words that pop into your head.

The reason why it’s important to write down three things—even if they are meaningless words—is twofold. First, it forces a momentary awareness of what you are thinking or feeling.

And why the fifteen-minute alarm? Because the point of these tests is to determine the reward you’re craving. If, fifteen minutes after eating a donut, you still feel an urge to get up and go to the cafeteria, then your habit isn’t motivated by a sugar craving. If, after gossiping at a colleague’s desk, you still want a cookie, then the need for human contact isn’t what’s driving your behavior.On the other hand, if fifteen minutes after chatting with a friend, you find it easy to get back to work, then you’ve identified the reward—temporary distraction and socialization—that your habit sought to satisfy.

By experimenting with different rewards, you can isolate what you are actually craving, which is essential in redesigning the habit.

Once you’ve figured out the routine and the reward, what remains is identifying the cue.

Step Three: Isolate the Cue

Our lives are the same way. The reason why it is so hard to identify the cues that trigger our habits is because there is too much information bombarding us as our behaviors unfold. Ask yourself, do you eat breakfast at a certain time each day because you are hungry? Or because the clock says 7:30? Or because your kids have started eating? Or because you’re dressed, and that’s when the breakfast habit kicks in?

To identify a cue amid the noise, we can use the same system as the psychologist: Identify categories of behaviors ahead of time to scrutinize in order to see patterns. Luckily, science offers some help in this regard. Experiments have shown that almost all habitual cues fit into one of five categories:

Location
Time
Emotional state
Other people
Immediately preceding action

So if you’re trying to figure out the cue for the “going to the cafeteria and buying a chocolate chip cookie” habit, you write down five things the moment the urge hits (these are my actual notes from when I was trying to diagnose my habit):

Where are you? (sitting at my desk)
What time is it? (3:36 P.M.)
What’s your emotional state? (bored)
Who else is around? (no one)
What action preceded the urge? (answered an email)

The next day:

Where are you? (walking back from the copier)
What time is it? (3:18 P.M.)
What’s your emotional state? (happy)
Who else is around? (Jim from Sports)
What action preceded the urge? (made a photocopy)

The third day:

Where are you? (conference room)
What time is it? (3:41 P.M.)
What’s your emotional state? (tired, excited about the project I’m working on)
Who else is around? (editors who are coming to this meeting)
What action preceded the urge? (I sat down because the meeting is about to start)

Three days in, it was pretty clear which cue was triggering my cookie habit—I felt an urge to get a snack at a certain time of day. I had already figured out, in step two, that it wasn’t hunger driving my behavior. The reward I was seeking was a temporary distraction—the kind that comes from gossiping with a friend. And the habit, I now knew, was triggered between 3:00 and 4:00.

Step Four: Have a Plan

Once you’ve figured out your habit loop—you’ve identified the reward driving your behavior, the cue triggering it, and the routine itself—you can begin to shift the behavior. You can change to a better routine by planning for the cue and choosing a behavior that delivers the reward you are craving. What you need is a plan.

In the prologue, we learned that a habit is a choice that we deliberately make at some point, and then stop thinking about, but continue doing, often every day.

Put another way, a habit is a formula our brain automatically follows: When I see CUE, I will do ROUTINE in order to get a REWARD.

To re-engineer that formula, we need to begin making choices again. And the easiest way to do this, according to study after study, is to have a plan. Within psychology, these plans are known as “implementation intentions.”

Take, for instance, my cookie-in-the-afternoon habit. By using this framework, I learned that my cue was roughly 3:30 in the afternoon. I knew that my routine was to go to the cafeteria, buy a cookie, and chat with friends. And, through experimentation, I had learned that it wasn’t really the cookie I craved—rather, it was a moment of distraction and the opportunity to socialize.

So I wrote a plan:

At 3:30, every day, I will walk to a friend’s desk and talk for 10 minutes.

To make sure I remembered to do this, I set the alarm on my watch for 3:30.

It didn’t work immediately. There were some days I was too busy and ignored the alarm, and then fell off the wagon. Other times it seemed like too much work to find a friend willing to chat—it was easier to get a cookie, and so I gave in to the urge. But on those days that I abided by my plan—when my alarm went off, I forced myself to walk to a friend’s desk and chat for ten minutes—I found that I ended the workday feeling better. I hadn’t gone to the cafeteria, I hadn’t eat a cookie, and I felt fine. Eventually, it got be automatic: when the alarm rang, I found a friend and ended the day feeling a small, but real, sense of accomplishment. After a few weeks, I hardly thought about the routine anymore. And when I couldn’t find anyone to chat with, I went to the cafeteria and bought tea and drank it with friends.

Obviously, changing some habits can be more difficult. But this framework is a place to start. Sometimes change takes a long time. Sometimes it requires repeated experiments and failures. But once you understand how a habit operates—once you diagnose the cue, the routine and the reward—you gain power over it.