The Power of Habit

By Charles Duhigg

Date: 19 December, 2019

Just the Highlights in : 9 Minutes

Buy the book Here

Summary and My Thoughts

Book notes are often a way for me to revisit books that I have previously read in an attempt to revisit the concepts that I may have forgotten in the time that has elapsed since I finished reading the book. Sometimes I create these notes immediately after I finish reading the book, sometimes it may be a year or more (as in the case with this book. Ever since I really began reading non-fiction on a consistent basis at the laughably young age of 24, I’ve found myself oftentimes reading for a therapeutic feeling, like I was doing something productive, versus actually comprehending and allowing the concepts to sink further into my head. If you’d like to exercise your comprehension skills, simply attempt to paraphrase the content of the book in a conversation with an interested listener (the key here being interested). Book notes, in a way, is my attempt to do just that, though with the aid of the source material at hand. I try to scan each chapter, highlight the high points, summarize in a terse manner (sometimes) and then share these notes with the internet.

This book introduces a few concepts, starting with the concept of the habit loop which proceeds from cue -> routine -> reward. Habits are formed by the brain to lessen the decision-making workload when encountering similar situations by forming this automatic routines that are triggered by specific cues with the goal of obtaining a specific reward. To change a habit, one has to be able to identify the cue and reward and simply replace the routine that follows from cue to the reward. Habits are powered by cravings and cravings are driven by the rush of endorphins produced by the reward of the habit loop. There are such things as keystone habits, or small wins/habits whose effects are propagated into creating a number of habits with a broader range of impact in both individuals and organizations. Willpower, like a muscle, can be fatigued by extensive use, yet self-regulatory and self-discipline practices can also strengthen willpower. Willpower is a key to success in life and the ability to make willpower into an automatic habit ensures this success. Societal habits are formed by both strong and weak relationships, these relationships can move in tandem to facilitate large social movements. Each chapter of this book includes at least two small interesting stories that describe the concepts discussed in the chapter.

Prologue: The Habit Cure

The chapter opens up on a case study of an individual, Lisa, whose life is on a considerable up-swing after a traumatic downward spiral that included a trip to Cairo, a divorce, and a desert trek; the key impetus in this change is her changing her habit of smoking, her keystone habit, which allowed her to transform other potentially terrible habits. Our lives and decisions are shaped by our habits. Habits can be changed. if we understand how they work.

Part 1: The Habits of Individuals

Chapter 1: The Habit Loop: How Habits Work

The chapter begins by detailing the tragic accident where a man named Eugene suffers a viral infection that destroys a medial temporal lobe portion of his brain that is typically responsible for memory recall and emotion regulation. While neuro-anatomy scientist, Squire, is working with Eugene, he recalls a case thirty years prior that involved a man named H.M. who suffered a similar brain impairment which essentially reset his experiences every few minutes. Unlike H.M. who had to spend the rest of his life in a facility under close observation, Eugene is able to to function somewhat though not able to do remember information or even make a map of his house that he traversed daily. Despite his injuries, Eugene was able to form new patterns. Scientists suspect that the basal ganglia (or the portion of the brain closest to the brain stem) is integral to habits. To confirm this, they monitored the activity of this portion of the brain in rats who were placed in a maze and tasked with finding a reward. As the rats started out, their brain activity spiked, however as they repeatedly solved the maze, their brain activity decreased. This change described the brain’s behavior to save effort by making a common routine into a habit. This habit loop is described as a three step loop that consists of a cue which tells the brain which habit to use, then a routine which can be physical, mental, or emotional, then the reward which helps the brain determine if this particular loop is worth remembering. Over time this loop becomes more automatic and the cue and reward become intertwined. When a habit emerges, the brain stops fully participating in the decision making, it reduces its effort, so unless you find a new routine or fight the habit, the pattern will unfold automatically.

Chapter 2: The Craving Brain: How to Create New Habits

As a way to successfully advertise Pepsodent toothpaste, an advertising genius stumbled upon the idea of creating a craving. A craving is what powers the habit loop. To form a craving you must first find a simple and obvious cue, next you clearly define the reward. In the case of Pepsodent, the cue was the “film on your teeth” and the reward was the “clean feeling/lack-of film”. P&G expanded upon this concept with their Febreeze product where the cue is an unwanted smell and the reward is the fresh scent of the Febreeze product. However in the case of Febreeze, the initial cue wasn’t effective which required P&G to go back to the drawing board. The endorphins rush when encountering the reward of the habit is what creates the craving that drives the habit loop itself. For a habit to last, you must develop the craving, your brain must start expecting the reward of the habit. Back to P&G example, after interviewing some successful customers of their Febreeze product they changed the habit loop from using the cue “getting rid of unpleasant smells” to use Febreeze, to acting upon the cue of “cleaning your house” to generate the reward of “using Febreeze” to enhance the smell of a newly cleaned room. Cravings drive habits and figuring out how to spark a craving makes creating a new habit easier.

Chapter 3: The Golden Rule Of Habit Change: Why Transformation Occurs

Buccaneers Head Coach introduces an important rule with his accomplishment of turning a losing football team into a winning football team: You can’t extinguish a bad habit, you can only change it. You simply keep the old cue and the old reward, but change the actual routine in the habit loop. The next anecdote featured in this chapter is the story of how Alcoholics Anonymous came to be. AA works because the program forces people to identify the cues and rewards of the habit loops that lead to drinking and then helps them find a new behavior to replace the routine. If you can identify the cues and the reward, you can change the habit. However, an additional ingredient is sometimes required and that is the actual belief that the habit can be changed and stay changed and this belief typically only emerges with the help of a support group.

Part 2: The Habits of Successful Organizations

Chapter 4: Keystone Habits, Or The Ballad of Paul O’Neil: Which Habits Matter Most

The featured story in this chapter follows the actions of Alcoa CEO whose pledge to make his company much safer resulted in identifying the concept of keystone habits, or habits that have the power to start a chain reaction, changing other habits as they move through an organization. Keystone habits rely on identifying the key priorities and fashioning them into powerful levers. To institute his zero work injuries policy, O’Neil, instituted a new process (or habit) where the cue would be when an employee was injured, the routine would be to come up with and communicated a prevention plan within 24 hours of the injury, and the reward would be that those who abide by this new plan would be promoted. To make this habit loop work, required that all the communication between the company hierarchy had to improve significantly to efficiently communicate the new prevention plans. As the safety record increased, the costs came down and the quality increased. Keystone habits are often small wins whose effects propagate, compound, and influence other habits and routines in a significant way.

Chapter 5: Starbucks and the Habit of Success: When Willpower Becomes Automatic

Will-power is an all-important habit, and the single most important keystone habit for individual success. Self discipline is a better indicator of academic and career success than simply IQ or intellectual talent. The best way to strengthen willpower is to make it automatic by turning it into a habit. Starbucks’ employee training philosophy successfully focuses on the development and cultivation of self-discipline and willpower. Originally, early experiments such as the marshmallow test determined that willpower was possibly a skills, but later research and experiments in the 1990s brought about the idea that willpower was more-so akin to a muscle that could become fatigued from overuse. Similarly to a muscle, willpower can be strengthened by practicing activities that build self-regulatory strength. You can develop willpower habits by creating action plans with specific goals and solutions to address commonly encountered obstacles to those goals. Starbucks has utilized this information in creating automatic routines for their employees to utilize when facing specific situations: the LATTE Habit loop.

Chapter 6: The Power of a Crisis: How Leaders Create Habits Through Accident and Design

This chapter mainly covered how organizational habits tend to organically form within companies through the various competing power relationships present within those companies. If left without guidance and leadership, these habits can form a chaotic and inefficient work environment (as detailed by the Rhode Island Hospital story within the chapter). Leaders must cultivate habits that both create a real and balanced peace and, paradoxically establishes a clear hierarchy within the organization. Another story mentioned in this chapter is how unwritten, unspoken rules, routines, and habits between the various division of the Underground led to the poor handling of a fire that eventually transformed into the tragic King’s Cross station fire. Good leaders use these moments of crisis to establish better habits and routines to prevent similar issues from arising in the future.

Chapter 7: How Target Knows What You Want Before You Do: When Companies Predict (and Manipulate) Habits

The story central to this chapter is how a statistician hired by Target was able to use data collected by customers’ purchases to determine their spending habits and even their current life situations for advertising purposes, a strategy employed by most retailers these days. Spending habits usually remain consistent unless a major life event happens (having a child, a divorce, moving, etc). Research has shown that the life event that carries the most opportunity for changing spending habits is the arrival of a new child, therefore a lot of the data analysis began to focus on predicting the arrival of new children to help manipulate customers into new spending habits. The rest of the chapter details the attempts to predict how to engineer a hit song. DJs discovered that one way to help a song gain traction in popularity is to sandwich its playing time in between two familiar songs.

Part 3: The Habits of Societies

Chapter 8: Saddleback Church and the Montgomery Bus Boycott: How Movements Happen

Movements start because of the social habits of friendship and strong ties between close acquaintances. Movements grow because of the habits of a community and the weak ties that hold neighborhoods and clans together. It endures because a movement’s leaders give participants new habits that create a fresh sense of identity and a feeling of ownership. These three characteristics are required for a movement to become self-propelling and reach critical mass. This is exemplified in the Montgomery Bus Boycott story detailed in this chapter. Weak ties are often more important strong ties because weak ties give us access to social networks that we otherwise don’t belong. It is important to capture the power of weak ties. The habits of peer pressure often spread through weak ties. When the strong ties of friendship and the weak ties of peer pressure merge, they create the powerful momentum necessary to create a movement. Rick Warren utilized these concepts in his introduction of small groups in building his largely successful Saddleback Church.

Chapter 9: The Neurology of Free Will: Are We Responsible for Our Habits

The chapter starts with the story of a housewife who begins a destructive gambling habit, a habitual routine that raises questions about the culpability and free will of a person who performs a destructive routine in an automatic, unthinking manner. The next story describes the tragic events of a man who, in a moment of sleepwalking, killed his wife on a camping trip while imagining that he was attacking a man who was attacking his wife. Sleepwalking is the brain inability to make the complete “switch” to paralysis when sleeping, which leads to people often physically acting out their dreams while unconscious. Sleep terrors are different because they involve the brain shutting down with the exception of the most primitive neurological structures which are known as the “central pattern generators”. These actions involved in sleep terrors are primal habits, automatic behaviors ingrained in our neurology that occur with no input from the higher regions of the brain. A sleep terror follows the habit loop wherever it leads with no conscious intervention. Habitual gamblers often perceive near-misses as wins whereas non-problem gamblers perceived near misses as losses and discontinue playing, it is unknown if this reaction is a genetic or biological component that people are born with. This chapter ends fairly sadly on both stories as the original story of the housewife gambler ends with her losing everything and the story of the husband who murdered his wife has to live with the fact that he killed the woman that he loved in an unconscious habitual act of terror.


Blake Adams is a writer, software developer, technical consultant, and financial independence enthusiast living in Oxford, MS.

Latest Posts

Goal Directed Living: Vision Boards and Affirmations

22 March, 2021


Goal Directed Living: Life Lists and More

21 January, 2021


A 2020 Update

03 September, 2020


Software Developer Career Tips: Closing Thoughts

12 February, 2020


Fitness Series: Illnesses and Injuries, Make a Contingency Plan

03 February, 2020


Latest Booknotes

The Power of Habit

19 December, 2019

Read My Highlights in 9 Minutes

Rich Dad Poor Dad

14 October, 2019

Read My Highlights in 10 Minutes

Atomic Habits

19 August, 2019

Read My Highlights in 16 Minutes