A Summary of The Power of Habit

A summary of the 2012 book by Charles Duhigg.

Introduction, and Summary of A Summary of The Power of Habit

The Power of Habit is a 2012 book by Charles Duhigg, which offers interesting models of human behaviour in terms of habits, extrapolated from some studies of human neurology, psychology, and behaviour. It focuses on modeling your own behaviour or the behaviour of groups you are a part of, for the purpose of making modifications to improve your ability to achieve your goals. It includes a great deal of practical advice along these lines.

I cannot speak to its accuracy, in this summary largely mostly repeat claims without analysis, and any serious fact checking would need to make use of the actual book, which includes 58 pages of details about its sources at the end. I do not feel it is amenable to summarisation, and also I can’t totally remove the point of buying the actual book, people reasonably frown on that.

I have let this summary expand relative to the length I was expecting to write, so I will make a very brief overview as well upfront.

The first five chapters, as well as the appendix, offer what I would suggest as the most personally, directly applicable parts of the book for an individual attempting to improve themselves, and are useful to read for anyone interested in those things. In brief:

The fourth through seventh chapter, overlapping with the above, discuss applicable strategies for leaders and agenty people to alter habits of people throughout groups and organisations they are involved in, and the ways companies alter habits of potential customers, clients, etc, that they interact with.

The eighth chapter provides a model of social movements in terms of habits, and how and why they take off or don’t. It is much less well evidenced and relies on a pair of examples it develops through the chapter, but the model is an interesting one and possibly a useful addition to a toolbox of models for social movements. In brief it posits:

The ninth and last chapter is probably mostly interesting to people who are not consequentialists, or who view free will as a concept with value; for me it was not so useful. It contains long stories about a compulsive gambler who was held legally responsible for their debts, and about a person who committed murder in their sleep who wasn’t, and concludes with an argument that the former is culpable while the latter is not because knowing a habit exists gives you responsibility to change it. If you can get through it without screaming internally at Caesars Entertainment you are again a lot more relaxed than I am. It does have some talk about differences between sleepwalking and sleep terrors.

Prologue: The Habit Cure

A group of neurologists, psychologists, geneticists, and a sociologist funded by the US National Institute for Health examined former smokers and overdrinkers who had turned their lives around, seeking to understand how.

One particular example was Lisa, who found themselves in Cairo depressed without direction after their life had collapsed, and decided that they would come back to Egypt and trek through the desert. That led to a conviction that they had to quit smoking in order to achieve their goal. That, in turn, led to replacing smoking with jogging, which in turn changed all their other habits, which led to improvements everywhere else. Smoking was a keystone habit; replacing it permitted reprogramming other habits. Brain activity typical of craving still existed, but was coupled with activity in areas associated with self-discipline.

Organisations can achieve similar degrees of change to outcomes by focusing on changing habits of staff and customers.

More than forty percent of the actions we perform each day aren’t actual decisions, but habits.

The book consists of three parts; habits in individual lives, habits in successful companies and organisations, and habits of societies. All revolve around the argument that habits can be changed if they are understood, and draw on many academic studies. A habit is defined as a choice that is made deliberately at some point, but then is continued automatically.

The author became interested in habits as a reporter in Baghdad. The US military is one of the biggest habit-formation experiments in history. Basic training teaches habits, and the battlefield relies on them. Thinking in terms of habits can be applied to modify behaviour; one major was able to prevent riots by having food trucks removed from the area riots would otherwise form in advance. They were enthusiastic about planning and designing habits as a way to run one’s life.

Part One - The Habits Of Individuals

Chapter 1 - The Habit Loop

In about 1992, a man named Eugene suffered severe damage to the medial temporal lobe in their brain as a result of viral encephalitis, leaving them unable to remember names, things they had said in the previous few minutes, and to perpetually remember outdated information, such as about their own age. In many respects they resembled a man named Henry Molaison from 1953 whose hippocampus was deliberately destroyed in an attempt to prevent seizures. However, unlike H.M, they could live at home with their wife, hold repetitive conversations, and perform complicated behaviours they learnt after the injury. Eugene could go out for a walk and find their way back, but not say where their house was, routinely go to the kitchen for food but be unable to point to the door leading to it.

Experiments showed that if an session in which Eugene was given pairs of objects, and asked to turn over the one with a correct sticker underneath, was repeated identically many times, they learnt to consistently turn over the correct object, but couldn’t understand how they knew to do so. Given all the objects together and asked to put the correct ones in a pile, they were unable to.

This demonstrates that they were forming new habits but not more general purpose memories, and their behaviour demonstrates that habit formation can encode remarkably complex rules independently of consciously accessible memory.

Experiments at MIT monitoring rat brains showed brain activity reduced as an activity, finding chocolate in a maze, was repeated. The basal ganglia, a small more primitive part of the brain, took over. This indicates that it handles recalling and acting on patterns. The complexity of our habits demonstrates that it can store remarkably complex patterns.

In order to identify when to start a habit, we learn something to recognise, which we call a cue. A habit consists of a loop, in which the cue triggers a routine, which ends with a reward; some change that indicates to our brain that the habit is worth remembering, and reinforces recognition of the cue. Over time, things fitting this loop become more and more automatic, and our brain stops participating fully in decision making.

Since the experiments with Eugene, habit formation has become a major field of study. Researchers have found that cues can be almost anything, including visual triggers, places, a time of day, an emotion, a sequence of thoughts, or particular company. They can be complex or very simple; some, such as those related to emotions, can be measured in milliseconds. Rewards can include both physical sensations from food or drugs, and emotional payoffs.

This process is necessary to not be overwhelmed by the minutiae of daily life. Damage to the basal ganglia causes trouble performing basic activities, such as opening a door.

By breaking a habit down into its components, we can learn to modify them.

Habits are fragile. If you remove or alter, even mildly, the reward or cue, a habit will cease triggering. However, it will still persist while unused, and when the conditions are restored the habit will go back to triggering. This makes modifying bad habits difficult. In order to replace habits, we must create new routines which overpower them.

They can be formed on purpose, as well as by accident. Things can be formed to provide more immediate rewards, and permit consistent routines to make them form more easily, and we do not generally notice this.

Habits we can’t change can become harmful. Eugene became very unhealthy as they aged, due to eating multiple unhealthy breakfasts. Only when the routines were entirely broken by removing all unhealthy food, and new habits established by placing salad next to them, were they able to improve.

Chapter 2 - The Craving Brain

Experiments monitoring the neurological activity of monkeys in the 1980s showed that if you train them that performing an action in response to a cue triggers a reward, they will begin to neurologically react to the cue the same way they react to the reward, in anticipation of the reward. If you then withhold the reward, they become unhappy and angry, and will decline to leave if offered the chance, in favour of holding out for the reward. Habits create cravings.

This means that if we encounter a cue, such as delicious smelling donuts or food on a plate, which has previously been associated with a reward, we will immediately feel some part of that reward and then craving for the real thing. This is used by businesses offering products that give rewards to manipulate you; Cinnabon, for example, wants you to be able to smell them from a distance, so you immediately feel a partial sense of what a cinnamon roll would be like, and feel a sense of craving and disappointment if you do not then go buy one.

This applies to all habits; a notification sound indicating the arrival of a potential distraction creates an immediate sense of enjoyment for the distraction, followed by a craving to then indulge in it. If you remove the notification sound, on the other hand, one can work for hours uninterrupted.

In order for a deliberately created new habit to stick, it must not only have a cue and a reward, but we must start anticipating the reward immediately in response to the cue. For a habit of exercise to stick, there must be some reward at the end, endorphin hit or otherwise, which we immediately begin craving in response to our chosen cue to start the exercise.

We can use this by deliberately attempting to envision the reward when we start a habit we are trying to create, until we begin to naturally anticipate it.

Advertising exploits the mechanics of habits. In the early 20th century, Claude Hopkins, author of My Life In Advertising, established toothbrushing as a daily ritual across America, and then much of the world. They did this by creating a craving.

Claude Hopkins advertised Quaker Oats as a breakfast cereal that provided energy for 24 hours, but only if eaten every morning. They advertised tonics to cure many things, but only if taken at first sign of fatigue or other symptoms. And they advertised toothpaste as to be used to get rid of the harmless film you can feel on your teeth. They described in their memoirs two basic rules: a simple and obvious cue, and a clearly defined reward, which remain a staple of advertising textbooks.

However, theirs was not the first toothpaste to be advertised with that language, and previous products had flopped. What they did that was different was include ingredients causing a cool, tingling sensation, that customers learnt to associate with cleanness, and on encountering the cue to start a habit, could crave in a way they couldn’t crave cleanness itself. Soon all the competitors came to add those ingredients, despite them not making the toothpaste perform any better.

When a Proctor and Gamble chemist found a chemical called HPBCD which removed smells, they first marketed it as a smell remover, under the name Febreeze. Using the principles of cue and reward, the cues they aimed for in their advertising were the smell of cigarettes and pet smells, and the reward was not smelling anymore. This flopped, because people become desensitised to smells around them, and so the cue did not work.

The solution was to use a cue and reward which were more amenable to creating a working craving in response to a recognisable cue. They added more perfume to Febreeze, and advertised Febreeze as something to be used after cleaning, to create a pleasant smell. This turned it into a hit.

There are other daily routines, with returns to our health similar to those from brushing our teeth, which we do not follow. Sunscreen reduces cancer risk, but we do not put it on every day, because there is no craving to make it a habit.

Chapter 3 - The Golden Rule of Habit Change

The golden rule of habit change is that you can never truly extinguish old habits, but can replace the routine of almost any habit if you keep the cue and reward the same. However, it only works if you believe the new routine will work; stressful circumstances can trigger reversion in the absence of some form of belief that grants certainty to the new routine, often caused by personal tragedy or tragedy affecting someone close to them, or caused by a change in their community.

This rule has influenced treatment for alcoholism and many other behaviours, and can be applied to your own habits.

In 1996, Tony Dungy used this rule to reform the perpetually losing Tampa Bay Buccaneers American Football team, focusing on instilling a smaller number of strategies to be performed near-automatically rather than a complex playbook. It worked and got far, but under pressure would break down. He later went on to work for the Colts, with similar results, until the team came together around the death of Dungy’s son.

Alcoholics Anonymous, although not obviously, works on this basis. Within its twelve steps, four (to make “a searching and fearless inventory of ourselves”) and five (to admit “to God, to ourselves, and to another human being the exact nature of our wrongs”) together lead you to find the cues for drinking habits. It then asks them to identify what rewards they get from drinking, which are often escape, relaxation, or companionship, and provides an alternative means for these things, allowing them to replace their routines for accomplishing them. Similarly, stressful events could cause reversion to old behaviour, but this was less common amongst those who believed in the spiritual elements about leaning on a higher power.

The golden rule of habit change has also been used in habit reversal therapy, to treat chronic nail biters, who bite their nails until they are pulled away from the skin, and others with similar problems, by asking them to record when they feel an urge to bite their nails, working out what it offers (such as a sense of completion or distraction) and then furnishing them with an alternative routine to do at those points which offers the same.

Part Two - The Habits of Successful Organisations

Chapter 4 - Keystone Habits, or the Ballad of Paul O’Neill

Some habits, known as keystone habits, can influence the development of other habits, so rather than trying to get everything right it is sufficient to focus on changing those habits which when changed will shift others. Recognising them is difficult; for unclear reasons, exercise functions as one for many people. They create new structures which enable other habits to thrive, often offering “small wins” directly but enabling further small wins. Finding and changing these works better than trying to change your entire life structure, because they stick easier.

Institutional processes, both private sector and government, can be understood as organisational habits, spread over bureaucrats and managers, who respond to cues in predictable ways to get rewards like promotions. These processes can be wildly suboptimal, and following them cedes control to something which occurred without actual thinking. The best institutions understand the importance of these habits.

Changes to organisational keystone habits can change culture.

In October 1987, Paul O’Neill took over as CEO of the aluminium manufacturing company Alcoa after previous management missteps. He immediately announced a singular focus on worker safety, alarming investors, but went on to improve profits massively, while at the same time safety improved greatly.

This was accomplished because the singular focus on safety required disrupting and replacing existing habits and processes within the company. O’Neill chose safety, because pursuing it provided the opportunity to change keystone habits affecting everything else, and it was something he could get everyone aligned on.

An early mandate was that any injury in the company had to be reported to O’Neill by the unit president within 24 hours along with a plan for making sure it didn’t happen again. In order to meet this mandate, the unit president had to find out about it almost immediately, which forced constant communication with floor managers, who had to get workers to raise warnings and provide suggestions on preventing the problem almost immediately. This forced the creation of new communication systems, which could raise an idea from the bottom of the company to the top as fast as possible.

Rules that could recognise processes performing poorly that had previously been resisted by either workers or management were adopted, because something going poorly was an indicator of risk of injury. Improvements to equipment that made injuries less likely also improved efficiency of operation. After an early strong response to an accident, O’Neill’s goals became well-regarded, and the processes that passed up safety concerns also passed up other ideas for improving operations, improving profits.

In 1996, after a decade, O’Neill had executives investigate claims of dangerous fumes in a factory in Mexico, and discovered that Robert Barton, one of the company’s most senior managers and important to various joint ventures, had failed to report a short-lived fumes build-up,which had caused some workers to become ill before being corrected by installing ventilation. They were fired within days of the investigation, a decision made easier because of the changes to institutional culture.

Since this, many companies have embraced the use of keystone habits to remake workplaces.

Bob Bowman, the coach for Michael Phelps, who won a gold medal swimming at the Beijing Olympics in 2008, used a focus on creating tiny moments of success in Phelp’s life and working them into a routine which could then lead to other moments of success, as well as practicing and visualising swimming until it became automatic, creating a focused and dedicated routine as well as instantly correct reactions while swimming itself.

Food journaling; simply recording what food is eaten; has proven more effective for dieting than attempting large life changes, because it sticks easier, and causes changes to other habits.

A young Paul O’Neill, working in government, worked to investigate the causes of the US’s high infant mortality rate. They found it was in part down to premature births, which was in part down to poor nutrition of mothers before pregnancy, which meant they needed better nutrition curriculums in high schools. However, many high school teachers in rural areas didn’t know enough biology to teach about nutrition. This led to the conclusion that changes were needed to how teachers were trained, in order to tackle infant mortality. By searching for a root cause that they could act on, they could cause a chain reaction of improvements which contributed to the 68% drop in infant mortality between when O’Neill started the project and today.

Chapter 5 - Starbucks and the Habit of Success

For one person, Travis, whose parents were addicts and who had been fired for subordination due to self-control problems, who was perpetually late, and who insulted themselves for not being better, a structured Starbucks training programme helped them get themselves together and resolve those problems, to the point that they became manager of two Starbucks stores.

The focus of this training programme is on willpower, in the sense of performing well in tests of self-discipline. Self-discipline is correlated with academic performance, and improvement in academic performance while studying. Willpower can be a habit, and making it a habit is how you strengthen it.

Willpower was of particular interest to Starbucks, because it needed to maintain a very high standard in how baristas interacted with customers in order to justify the high prices it charges for coffee, which required them to have a great deal of it, but recruits often had not previously had professional experience. This led to them spending millions to develop curriculums to teach it.

An old experiment from Stanford in the 1960s took children and left them unsupervised with a marshmellow, having told them that if they didn’t eat the marshmellow, then they’d get two marshmellows when the researcher came back. The children who didn’t eat the marshmellow, demonstrating better self-discipline, went on to achieve better academic results in life.

Subsequent experiments showed that teaching the child tricks, like distracting themselves by drawing a picture, or imagining a frame around the marshmellow making it just a picture, would help them learn self-control, leading to the consensus in the 1980s that willpower was a learnable skill, by which time funding for research had dried up.

In the mid 90s, some researchers found these answers unsatisfying, as if willpower were a skill, you’d expect it to remain consistent day to day, and planned further experiments. They told subjects to skip a meal, put out bowls of radishes and warm cookies, told them to eat one or the other allegedly as part of a taste perception experiment, and then had them do a puzzle allegedly as a gap before the next phase of the experiment. The puzzle was impossible, and they measured how long it took for the subject to give up. People who had been told to eat the radishes gave up in 40% of the time as the people told to eat cookies.

The conclusion, backed by subsequent studies, was that willpower was also akin to a muscle; it gets tired as it is used, leading to less available for subsequent things.

Subsequent experiments by Australian scientists starting in 2006 enrolled people in gyms, money management programmes, and academic improvement programmes to test how they affected the rest of their lives, and found that the people smoked less, drank less, watched less television, and showed improvements in other aspects of their lives despite them not being explicitly mentioned. This showed that willpower improved over time with use, and practicing it improved willpower elsewhere in life. A mechanism for this, proposed by a researcher at Dartmouth, is that this is because you learn habits for how to distract yourself from temptations.

Many firms, including Starbucks, have tried applying this research. Starbucks’ first approach was sponsoring weight-loss classes and offering free gym memberships, hoping for benefits to spill over. They found attendance was spotty; people with self-discipline problems at work were even less likely to show it out of work.

In 1992, a psychologist recruited elderly patients who had recently undergone hip or knee replacement surgery and needed to reliably perform painful exercise in order to recover correctly, and gave them booklets describing their rehab schedule, with blank pages at the back for writing in their own plans. Three months on, they found that patients who had written plans into their booklet were walking twice as fast, and getting in and out of their chairs almost three times as fast.

A common element was that they would write in a routine for handling a specific moment of pain, such as taking a first step immediately after standing up so they wouldn’t be tempted to sit down again, and their plans would end with something satisfying. They identified simple cues, and obvious rewards, and could resist the temptation to give up because they had crafted a habit around the self-discipline needed to keep going at the specific moment of pain.

Starbucks’ second approach was built on these lines; they provided a range of processes and routines and methods to follow at inflection points, such as angry customers, which stressed self-discipline, drilled their employees on them until they became automatic with large amounts of time spent in training, and had their employees write out how they planned to respond. And they found these methods worked, as have other companies such as Deloitte and the Container Store which have also developed processes and routines.

Looking into results further, some people seemed to learn willpower habits readily, while others didn’t. A further experiment, in which some people were given polite requests to do a willpower-requiring activity while others given brusque instructions, followed by tests, showed that doing something as a result of a polite request used less willpower. The conclusion drawn from examining the experiment was that a sense of agency improves willpower greatly. Companies which have tried putting this into effect, by arranging things to give employees this sense, have seen improved employee performance.

Chapter 6 - The Power of a Crisis

Institutional habits exist in any organisation, and will emerge in an unplanned manner if not managed. In an organisation with problems, toxic institutional habits can emerge as staff create informal norms to work around the problems. These can create potential for accidents.

Many decisions organisations make which people assume are the result of rational deliberation are actually made as the result of habitual processes. These processes are important, as they permit staff to experiment without needing approval for every action taken, and permit institutional memory.

Habitual processes also serve as truces between executives and divisions competing for success, with conflicts over allocation of expenses and division of duties and who has to do what for whom when. Individually selfish behaviour is normal. Organisational habits and norms define the behaviours which will enable the company to continue to function despite the competition. A common one of these is that anyone who goes too far finds their peers unite against them.

If these processes do not permit all the parties to affect the things they need to, then they are prone to fail, as one party is unable to make things that need to happen happen. However, it isn’t enough to simply make power be balanced between parties, because then the lack of any single person responsible for, say, safety, with the ability to override other parties, can cause failures for that concern to be properly implemented.

A sense of crisis creates a situation where organisational habits are malleable enough to change allocation of responsibility and make processes more equitable, to the point it can be worth deliberately inducing. Good leaders seize them to improve the organisation, and alter the habits and truces so that balance of power in general is equitable, but there is clear allocation of responsibility in a clear chain of command for managing safety or other critical concerns, with a responsible person who is able to override other concerns when needed.

A Pair of Longer Case Studies

Rhode Island Hospital in the mid 2000s had problems with doctors having power over nurses and no expectation of manners or professionalism, including in handling correction. The result was a set of norms and codes and habits worked out by the nurses to work around and warn each other of unreasonable doctors. This led to a death after a surgeon insisted on performing surgery to treat blood pooling in the brain (hematoma) with incomplete documentation missing the side that the hematoma was on, and nurses, having noted this surgeon as being unreasonable in the past, did not feel able to object.

This was a case where organisational habits, that constituted truces between the nurses and doctors needed for the organisation to function, were too imbalanced.

After more similar events, the hospital faced a crisis as critics and the media began to pile on. In response to the crisis, administrators were able to shut down all elective surgery for a day, force staff through an intensive training programme, and implement changes recommended by the Center for Transforming Healthcare, including checklists, video cameras in operating rooms, and a system for anonymously reporting problems endangering patients, which had been previously proposed but faced staff pushback.

Another example of dysfunction caused by poor organisational habits and truces, which will be elaborated on in more detail, occurred in the London Underground, in 1987. At the time the main leadership was the “Four Barons”; the chiefs of civil, signal, electrical, and mechanical engineering, and there were many habits by which all their respective staffs avoided stepping on each others’ toes.

This led to a noticed burning tissue being ignored, as the staff member who it was reported to had no way to report it further, as fire safety was handled by another department and rules prevented interdepartmental communication not authorised by a superior.

Further reports which did reach the safety inspector were handled slowly, without reporting them to the fire brigade, because of an unwritten rule that they were not to be involved unless absolutely necessary. Earlier warnings of unpreparedness and urges to call the fire brigade quickly were not reacted to, because they were delivered to a different department and had never been read. An escalator sprinkler system had been installed as a result of those warnings, but no one inside the station had been trained in its use. Similarly, the extinguishers were controlled by another department, and no one inside the station was authorised to use them.

The fire brigade were first notified as a result of a police officer walking upstairs to where their radio worked and calling their superiors, who eventually passed on a report of a small fire.

The safety inspector discovered that the escalator machine room was already burning out of control by the time they reached it, and reported the need to evacuate the station to a police officer.

Almost half an hour after the initial report, passengers were noticing smoke, a smell of burning, and beginning to leave on their own slowly. The hot air from the burning escalators was accumulating against the layers of old paint on the ceiling, heating them. The director of operations had previously recommended the removal of older layers of paint to avoid a fire hazard, but painting protocol was the responsibility of the maintenance department, which rebuked them for interfering outside their department, leading to the recommendation being withdrawn.

When a train arrived shortly after, forcing a large gust of air into the station, the oxygen fed the fire, causing the superheated gases to rapidly reach their flashover point, causing everything in the elevator shafts to ignite in a fiery blast. The force of the sudden incineration caused the trench effect, a previously unknown combination of mechanics which pushed the fire upwards through the long shaft, gaining heat and velocity, until it shot out of the shaft into the ticketing hall, melting the flesh of the passengers inside, who had not been evacuated as the fire had previously appeared to be contained.

Thirty-one died, with dozens of injuries.

In this case, the truces represented an equitable balance of power, but no single person with authority over the entire system was in charge of safety, causing numerous deaths.

A special investigator, Desmond Fennell was appointed by the Secretary of State to identify problems. They found that people in the Underground had known for years that fire safety had been a problem, reforms had been proposed, but none had been implemented. When he made his own recommendations, he also had pushback from department heads, undercutting them with instructions.

Fennell responded by creating a media circus. They called for public hearings which lasted for 91 days, and exposed the ignored warnings. They implied to reporters that they were at risk every time they rode the Underground. He cross-examined dozens of witnesses who described the prioritisation of turf battles over safety, and ultimately published a 250 page indictment of the organisation, ending with pages of recommendations which accused large parts of the organisation of being either corrupt or incompetent.

The result was picketing, the organisation’s leadership being fired, new laws, and wholesale cultural overhaul. The truces still exist, but were altered enough to create a single person in charge of safety at each station, and give every employee responsibility to report them.

Chapter 7 - How Target Knows What You Want Before You Do

Companies hire statisticians to go over sales data and work out answers to questions like whether a joke is funnier in one colour or another, or whether birthday cards sell more with one animal or another.

Older marketing tricks, still in use, include putting fruits and vegetables near the entrance, because after loading up on fruits and vegetables shoppers are more likely to spend on unhealthy impulse buys, having acquired a sense of virtuousness. They also put all the most profitable goods to the right of the entrance, as shoppers almost always turn right on entry, and put soups and cereals in an unpredictable order, because by forcing shoppers to look through the shelves they increase the odds of the shopper choosing to buy something else.

These are effective, but are one-size-fits-all solutions, treating each shopper identically. Consumers buy habitually, but all have differing habits. Some large companies, Target being an example, gather large amounts of data on these habits, and the frequencies with which certain products are bought, and correlate them with other characteristics. For customers who they can identify, they can purchase data providing their ethnicity, job history, reading habits, political leanings, reading habits, and based on online photographs, approximate physical attributes, among many other details, to aid in this process.

If they see you are likely buying something routinely, but buying it from someone other than them, they can send you personalised coupons for that particular thing. If they identify you might be interested in something, they can send you coupons for that; for example, Target would send customers who bought bikinis in April coupons for weight-loss books in December. Almost every major retailer has a “predictive analytics” department using methods like these.

Large supermarkets such as Target can recognise, to a workable degree of probability, when a major event has occurred in your life on the basis of the contents of your shopping basket.

Certain events in life, such as moving house, getting married, getting a divorce, and more than any other, having a baby, are disruptive to existing habits and lead to new ones being formed. By targeting you when you’re going through these events with marketing aimed at things you might need, the store can create a greatly improved chance that the new habits you form to meet your new needs will involve giving them lots of money going forwards.

This is especially valuable because in the immediate aftermath of such events, most people will opt for whatever is easiest rather than whatever is cheapest, meaning you can accomplish this without having to be especially cheap. Marketing schemes targeting new parents in hospitals exist, with giveaways of items, for this reason.

By using shopping data from customers who were using the baby registry, Target was able to develop a method for recognising customers who were likely pregnant, and a probability distribution for their due date, which could then be applied to their customers more broadly to market to them before other companies did, which was used to mail out coupons. This worked effectively, even where the pregnancy was a secret; in one instance, this resulted in coupons for items for a new baby being sent to a teenager who hadn’t yet told their family they were pregnant.

This resulted in public relations problems, as customers didn’t like realising that Target knew what they knew. This lead to a desire to make use of this information without the subjects noticing. The solution was to send out personalised coupons, but hide the targeted coupons among others, making it non-obvious that the coupon booklet was personalised.

Similar analysis has been applied to music, in an effort to identify which songs will be hits, and to identify which songs will be sticky; that is, will not result in a listener turning off the music. This occasionally made dramatic mispredictions.

Being sticky is not the same thing as being consciously liked, and often things people consciously dislike are sticky. Being sticky seems to have a relationship with familiarity and similarity, and this book proposes the theory that this is because familiar sounds are a cue that tells us that if we complete listening we will get a reward of some kind, like a sense of the song being catchy, causing us to habitually listen instead of switching what we are listening to.

Standard playlist theory now is to sandwich new songs between two already sticky songs, until such time as they become sticky themselves. The previous dramatic mispredictions from the data were songs that were not presently sticky, but were amenable to being sticky with this technique.

The general technique of offering people what they really will pay money for or keep coming to you for, mixed in with the things that they endorse themselves as wanting, is a common one.

Part Three - The Habits Of Societies

Chapter 8 - Saddleback Church and the Montgomery Bus Boycott

A social habit is a habit which relates to how we interact with each other. There are other routes by which society can be changed, but at the root of many movements is a three part process:

Usually all parts need to be in place for a movement to reach critical mass.

They start because of friendships, ties with close acquaintances, and supportive social habits associated with those things. People join protests because people they know are involved, out of friendship. But alone this is not enough to make a protest more than a one-day event.

A person’s weak ties, distant acquaintances and friends of friends, are often more impactful than their near ties, because they grant access to distant social networks. Having few weak ties puts you in a disadvantaged position in the labour market, and a social movement starting amongst people with weak ties will struggle to spread beyond a small clique.

Social movements spread through weak ties via peer pressure, which functions adequately across them. A sense of obligation to engage in a protest, even if you don’t want to, is how that protest can become pervasive throughout a larger community. This sense is created through a threat that if you shrug off the request, you risk losing your social standing and weak ties, because of a credible possibility that people may talk about your decision not to participate across clique lines, and disfavour you for it. This creates participation in the protest within a wider community.

One particular mechanism by which this operates is that you are very unlikely to back out of a commitment to participate in something if your community groups will judge you for it, whereas a similar level of participation in non-judgemental community groups leads to more backing out.

The combination of reinforcement from weak ties and interaction with strong ties, combined with the right ideas, can then create new habits and identity which make people sustain the movement even in the absence of the original pressures.

The Examples

Rosa Parks was not the first to be arrested in Montgomery. What distinguished her from the others was that she was deeply respected and embedded within her community, which triggered an initial protest out of the habits of friendship.

At the time, Montgomery’s social fabric was formed of many hundreds of small tight-knit groups, and Rosa Parks and her friends were involved in many of them. This led to her being bailed by a prominent lawyer and a former head of the Montgomery NAACP, and then to the president of a local group of schoolteachers involved in politics, a friend of Rosa Parks, calling an impromptu meeting, and suggesting a boycott on the date Parks was to appear in court, then printing flyers, which they asked the group to distribute. Many of the people who received a flyer knew Parks, and out of the natural sympathy of friendship joined the initial boycott. However, this would not, in itself, have been enough to make the protest more than a one-day event.

Due to campaigning done through personal connections, Martin Luther King was brought onboard, and after talking with the city’s black ministers, and three days after the arrest on Sunday, they explained to their congregations that the churches had agreed to a one-day boycott, creating a sense that it would be embarrassing for anyone to sit out. The local newspaper, having gotten copies of the fliers via white citizens, published an article saying that the city was flooded with thousands of the fliers, and that they were expecting every black citizen to participate, which led to everyone assuming that everyone else was already onboard. Finally, everyone heard that the black taxi drivers had been convinced by the boycott’s leaders to carry black passengers for the price of a bus fare.

The community’s weak ties had left everyone either for or against the boycott, and they stood together because anyone who didn’t participate was at risk of appearing to be someone no one would have wanted to be friends with in the first place.

This led to many people attending the courthouse, and when Rosa Parks was found guilty, the impromptu rally was the most significant black political activism in the area’s history and led to the boycott being extended.

The boycott began to waver after a couple of months, with police and the authorities attempting to undermine workarounds adopted by the community to allow them to continue working, before a bomb was detonated outside Martin Luther King’s home. In response King gave a speech calling for non-violent activism and embrace, framing the conflict as part of God’s plan, a continuous part of the same narrative as the end of British colonialism, American slavery, and the death of Christ, with victory ultimately inevitable. By framing the conflict in such terms, rather than as a simple battle, they offered a new identity as people part of an inevitable force of progress. The people who took it on gained a sense of investment in the cause, and acted to lead it, with further bombings and violent opposition simply confirming this identity rather than discouraging the activists.

It has been argued that what led to the change in the law that ended segregation on the buses was the Supreme Court decision, rather than the boycotts; in any case, the now distributed and self-propagating self-leadership in the movement spread its changes in social habits widely, through ties to communities across America, changing the nature of the civil rights movement going forward.

In 1979, a Baptist pastor called Rick Warren set off to a place called Saddleback Valley, after looking for a location with high numbers of self-identified Christians but few churches, as a place to start a church. They were guided by the principle that missionaries should appeal to social habits, speak to people in their “own languages”, convert entire communities so that social habits reinforced belief, and get to the point that people follow Christ because “following Christ” is a core part of their identity.

Starting out the church with a focus on making the sermons practical and entertaining, they hit 200 members in under a year, before under the extreme workload they set for themselves they began to suffer panic attacks and strong bouts of depression, causing them to stop services for a while. On resuming, they took a step to make it less work for themselves; they had church members form groups, and meet in their homes for classes, instead of running them at the church. These were popular, but became distracted from religion, leading to Warren attempting to alter people’s habits so their natural inclination was to discuss religion in them, by creating a curriculum for these groups which instructed people that to have a Christ-like character they just needed to develop the habits that Christ had.

Soon every new church member was asked to sign a “maturity convenant card”, promising to adhere to three habits; daily quiet time for reflection and prayer, tithing 10%, and membership in one of the church’s groups.

In this case, the large weakly tied group comes first, the large congregation drawing new adherents. Then the strong ties come second, with the small group the new member joins. And finally, the curriculum coupled with pressure from both strong ties and the weaker ties leads to change in habits and self-identity that lead people to sustain the religious community on their own.

Chapter 9 - The Neurology of Free Will - Are We Responsible For Our Habits?

We take a person, Angie Bachmann, as an example of a person who developed a gambling problem. After her daughters left, she was extremely bored at home, and started going to casinos, which immediately offered some fun. She adopted strict rules, knowing gambling was risky, but after getting better at making her money last she adjusted them to spend longer gambling.

After her parents started showing signs of lung disease, she started visiting them on alternative weeks, which aggravated the sense of loneliness when home, as her absence disrupted the few routines keeping her busy. This led to a range of bad feelings, all of which were alleviated by a trip to the casino. She still had rules, but had bought into the idea that she could make money by following them and continuing losses, was now habitually making the ‘right’ moves while gambling, and the rules gradually became more flexible to permit those habits.

The size of her winnings and losses expanded. She wasn’t keeping track of them herself, after the casino offered a line of credit to avoid carrying cash. Naturally, the losses exceeded the winnings on average, and as they scaled up she found she didn’t have enough money to pay bills, and then began borrowing money from her parents to keep the home running.

In 2001 she was going to the casino nearly every day, her debts hit $20,000, and after her parents cut her off she finally revealed them to her husband. They hired a bankruptcy attorney, cut up her credit cards, and took steps to plan for a more austere life. This worked for years, until both her parents died, and she gained a million dollar inheritance. She bought her family a new home with it, in a state where gambling wasn’t legal, but while picking up furniture, during a moment of pain, she elected to return to the casino, and gambled for hours after unloading to a manager.

The casino company, now known as Caesars Entertainment, operated an analytics-driven marketing system, which studied gamblers’ habits in order to identify how to encourage them to gamble more, using methods such as telemarketers calling them at home. A difference between problem gamblers and non-gamblers is that problem gamblers react habitually to a near-miss the same way they do to a win, whereas non-gamblers react by quitting before it gets worse, and they, like many other casinos and scratch cards, exploit this by artificially increasing the number of near misses and introducing small payouts that are less than the amount which went in.

Soon after Angie’s first return to the casino, despite knowing about the bankruptcy, the casino company began making phone calls offering her limos and flights to casinos, with free airfare and rooms for everyone who wanted to go. At first she resisted, but then she began accepting the offers, being amazed by ridiculously luxurious hotel rooms. At first she spent free credit offered in the casinos, but predictably ended up spending her own again, making trite rationalisations to justify it.

In a visit back to her hometown for her husband’s grandmother’s funeral, she visited her original casino again, and over the span of twelve hours lost $250,000. She didn’t tell her husband, because of the shame. The casino company kept calling, and she convinced herself she could win it back, because if you couldn’t win then surely gambling wouldn’t be legal.

When she was almost broke, Harrah offered her a line of credit to fly out anyway, and gambled on credit until the casino said no. She had taken out a line of credit on her home, so it had been lost as well. Her lawyer ultimately ended up arguing before the state’s highest court that she shouldn’t be held culpable for these losses because she gambled out of habit rather than choice. This argument failed.

In 2008, a man in Wales, Brian Thomas, killed his wife by strangulation directly after being asleep, before turning himself into the police, claiming that he had believed them to be an attacker. The man had had a history of sleepwalking, to the point that the house door was kept locked and he routinely slept in a different room to avoid disturbing the wife while at home. In court, they argued that they had been asleep at the time the crime was committed, and so was not culpable.

Sleepwalking occurs when the switch between being awake or asleep occurs incorrectly, leaving them incompletely paralysed, causing them to act while they dream. People act out complex habits without input from the brain’s more advanced regions. However, they usually avoid danger.

Sleep terrors, based on analysis of the brains of sleepwalkers, are something different. During a sleep terror, people seem to be in the grip of terrible anxiety, but are not dreaming. The only things active are the most primitive parts of the brain, leading to a brain which looks a lot like it is following a simple habit, except without the possibility of conscious intervention. The two most common sleep terror experiences are feeling threatened and feeling sexually aroused, and people respond to either by following the habits cued from that stimuli. Sleepwalking seems to permit enough involvement of higher brain functions that we avoid danger, or terrible actions; during sleep terrors people simply follow the habit loop wherever it leads.

A tendency towards sleep terrors seems to be present in some people, and over 150 criminals have avoided punishment using automatism as a defence, as Thomas did in this case.

The book argues that these differing verdicts are just, because once you know a habit exists, you have responsibility to change it, and this was the case in the former circumstance but not the latter, and states that to a large extent the point of the book is that it is possible.

William James, who died in 1910, hailed from an accomplished family, but had met with failure as an artist and at medical school. Despondent about their life, they decided that before doing anything rash they would do a yearlong experiment, during which they would force themselves to believe that they could change, and to believe that they had free will. And during that year they wrote in their diary as though it wasn’t in question, and things went well for them, and two years later they wrote a letter to the philosopher Charles Renouvier, who expounded at length on free will, thanking them.

The book expresses the standpoint that if you believe you can change, it makes change happen, and that habits are what we choose them to be, that they are the “water in which we exist” and that by making that water visible you gain power over it, and so can now “swim”.

Appendix: A Reader’s Guide To Using These Ideas

Using these ideas to change a habit boils down to four steps: