Thinking, Fast and Slow

by Daniel Kahneman

Surprisingly, the patients did nothing of the kind. The statistical analysis revealed two findings, which illustrate a pattern we have observed in other experiments: Peak-end rule: The global retrospective rating was well predicted by the average of the level of pain reported at the worst moment of the experience and at its end. Duration neglect: The duration of the procedure had no effect whatsoever on the ratings of total pain.

two measures of experienced utility—the hedonimeter total and the retrospective assessment—that are systematically different.

the retrospective assessments are insensitive to duration and weight two singular moments, the peak and the end, much more than others.

What should the physician do? The choice has implications for medical practice. We noted that: If the objective is to reduce patients’ memory of pain, lowering the peak intensity of pain could be more important than minimizing the duration of the procedure. By the same reasoning, gradual relief may be preferable to abrupt relief if patients retain a better memory when the pain at the end of the procedure is relatively mild. If the objective is to reduce the amount of pain actually experienced, conducting the procedure swiftly may be appropriate even if doing so increases the peak pain intensity and leaves patients with an awful memory.

find it helpful to think of this dilemma as a conflict of interests between two selves (which do not correspond to the two familiar systems). The experiencing self is the one that answers the question: “Does it hurt now?” The remembering self is the one that answers the question: “How was it, on the whole?”

illustrates the difficulty of distinguishing memories from experiences.

Confusing experience with the memory of it is a compelling cognitive illusion—and it is the substitution that makes us believe a past experience can be ruined.

What we learn from the past is to maximize the qualities of our future memories, not necessarily of our future experience. This is the tyranny of the remembering self.

Fully 80% of the participants who reported that their pain diminished during the final phase of the longer episode opted to repeat it, thereby declaring themselves willing to suffer 30 seconds of needless pain in the anticipated third trial.

The cold-hand experiment, like my old injections puzzle, revealed a discrepancy between decision utility and experienced utility.

Other classic studies showed that electrical stimulation of specific areas in the rat brain (and of corresponding areas in the human brain) produce a sensation of intense pleasure, so intense in some cases that rats who can stimulate their brain by pressing a lever will die of starvation without taking a break to feed themselves.

only intensity matters.

In the cold-hand experiment, the error reflects two principles of memory: duration neglect and the peak-end rule. The mechanisms are different but the outcome is the same: a decision that is not correctly attuned to the experience.

A story is about significant events and memorable moments, not about time passing.

This is how the remembering self works: it composes stories and keeps them for future reference.

Caring for people often takes the form of concern for the quality of their stories, not for their feelings.

In spite of my long experience with judgment errors, I did not believe that reasonable people could say that adding 5 slightly happy years to a life would make it substantially worse. I was wrong. The intuition that the disappointing extra 5 years made the whole life worse was overwhelming.

In intuitive evaluation of entire lives as well as brief episodes, peaks and ends matter but duration does not.

Duration appears to matter in these situations, but this is only because the quality of the end changes with the length of the episode.

Statistical analysis established that the intentions for future vacations were entirely determined by the final evaluation—even when that score did not accurately represent the quality of the experience that was described in the diaries.

As in the cold-hand experiment, right or wrong, people choose by memory when they decide whether or not to repeat an experience.

most people are remarkably indifferent to the pains of their experiencing self.

Odd as it may seem, I am my remembering self, and the experiencing self, who does my living, is like a stranger to me.

I was naturally suspicious of global satisfaction with life as a valid measure of well-being. As the remembering self had not proved to be a good witness in my experiments, I focused on the well-being of the experiencing self.

flow—a state that some artists experience in their creative moments and that many other people achieve when enthralled by a film, a book, or a crossword puzzle: interruptions are not welcome in any of these situations.

The resistance to interruption was a sign I had been having a good time,

I was inclined to dismiss Helen’s remembering self as an error-prone witness to the actual well-being of her experiencing self. I suspected this position was too extreme, which it turned out to be, but it was a good start.

Mood at work, for example, is largely unaffected by the factors that influence general job satisfaction, including benefits and status. More important are situational factors such as an opportunity to socialize with coworkers, exposure to loud noise, time pressure (a significant source of negative affect), and the immediate presence of a boss (in our first study, the only thing that was worse than being alone). Attention is key. Our emotional state is largely determined by what we attend to, and we are normally focused on our current activity and immediate environment.

In normal circumstances, however, we draw pleasure and pain from what is happening at the moment, if we attend to it.

These observations have implications for both individuals and society. The use of time is one of the areas of life over which people have some control. Few individuals can will themselves to have a sunnier disposition, but some may be able to arrange their lives to spend less of their day commuting, and more time doing things they enjoy with people they like.

another way to improve experience is to switch time from passive leisure, such as TV watching, to more active forms of leisure, including socializing and exercise.

the second best predictor of the feelings of a day is whether a person did or did not have contacts with friends or relatives.

More education is associated with higher evaluation of one’s life, but not with greater experienced well-being.

On the other hand, ill health has a much stronger adverse effect on experienced well-being than on life evaluation.

Religious participation also has relatively greater favorable impact on both positive affect and stress reduction than on life evaluation. Surprisingly, however, religion provides no reduction of feelings of depression or worry.

The conclusion is that being poor makes one miserable, and that being rich may enhance one’s life satisfaction, but does not (on average) improve experienced well-being.

A headache increases the proportion reporting sadness and worry from 19% to 38% for individuals in the top two-thirds of the income distribution. The corresponding numbers for the poorest tenth are 38% and 70%—a higher baseline level and a much larger increase.

The satiation level beyond which experienced well-being no longer increases was a household income of about $75,000 in high-cost areas (it could be less in areas where the cost of living is lower). The average increase of experienced well-being associated with incomes beyond that level was precisely zero.

A plausible interpretation is that higher income is associated with a reduced ability to enjoy the small pleasures of life.

The general conclusion is as clear for well-being as it was for colonoscopies: people’s evaluations of their lives and their actual experience may be related, but they are also different.

In the useful term introduced by Daniel Gilbert and Timothy Wilson, the decision to get married reflects, for many people, a massive error of affective forecasting. On their wedding day, the bride and the groom know that the rate of divorce is high and that the incidence of marital disappointment is even higher, but they do not believe that these statistics apply to them.

Even when it is not influenced by completely irrelevant accidents such as the coin on the machine, the score that you quickly assign to your life is determined by a small sample of highly available ideas, not by a careful weighting of the domains of your life.

Experienced well-being is on average unaffected by marriage, not because marriage makes no difference to happiness but because it changes some aspects of life for the better and others for the worse.

One reason for the low correlations between individuals’ circumstances and their satisfaction with life is that both experienced happiness and life satisfaction are largely determined by the genetics of temperament.

People who appear equally fortunate vary greatly in how happy they are.

In part because of these findings I have changed my mind about the definition of well-being.

We cannot hold a concept of well-being that ignores what people want. On the other hand, it is also true that a concept of well-being that ignores how people feel as they live and focuses only on how they feel when they think about their life is also untenable.

The concept of happiness is not suddenly changed by finding a dime, but System 1 readily substitutes a small part of it for the whole of it.

This is the essence of the focusing illusion, which can be described in a single sentence: Nothing in life is as important as you think it is when you are thinking about it.

But climate was not an important determinant of well-being. Indeed, there was no difference whatsoever between the life satisfaction of students in California and in the Midwest.