Blink Summary and Analysis of One: The Theory of Thin Slices: How a Little Bit of Knowledge Goes a Long Way


Gladwell gives the example of a young couple that came to the University of Washington to psychologist John Gottman’s lab. Both the guy and the girl were twenty-somethings, blond, blue-eyed, and stylish. They were likable, intelligent, and attractive. They were led to a room in which electrodes were attached to their bodies (measuring things like body temperature, heart rate, sweat, etc.) and left alone for fifteen minutes with the cameras rolling. They were told to discuss any topic from their marriage that had become a point of contention. They discussed their dog: the guy, coded as Bill, did not like the dog, the girl, coded as Sue, did like it. The videotape at first seemed like a random sample of a very ordinary kind of conversation that most couples tend to have: no scenes, no violence, and no breakdowns.

To make an accurate prediction of a marriage it would seem necessary to gather a lot of information and in many different contexts as possible. But John Gottman has proven that such extensive work is unnecessary. Since the 1980s, Gottman has brought over three thousand married couples into his “love lab,” and each couple has been videotaped. The results have been analyzed according to what Gottman calls the SPAFF (for specific affect) – a coding system that has twenty separate categories corresponding to every conceivable emotion that a married couple might express during a conversation. He has taught his staff to read every emotional nuance in people’s facial expressions and how to interpret seemingly random bits of dialogue. When they watch a video, the staff assigns a SPAFF code to every second of the couple’s interaction. The data from the electrodes and sensors is factored in, and all of that information is fed into a complex equation.

Through these calculations, Gottman has proven that he can predict with 95% accuracy whether that couple will still be married fifteen years later. If he watches a couple for fifteen minutes, his success rate is around 90%. Gladwell states that there is nothing instinctive about Gottman’s approach, and that he is not making snap judgments. His work is an example of conscious and deliberate thinking. But Gottman is a master of “thin-slicing” – a part of rapid cognition that refers to the ability of the unconscious to find patterns in situations and behavior based on very narrow slices of experience. When the unconscious engages in thin-slicing, the mind is doing an automated, accelerated unconscious version of what Gottman does with his videotapes and equations.

On a technical level, Gottman’s staff measures the amount of positive and negative emotion. For a marriage to survive, the ratio of positive to negative emotion in any given encounter has to be at least five to one. Gladwell analogizes Gottman’s insights on marriage to what people in the world of Morse code call a fist: a relationship between two people has a distinctive signature that arises naturally and automatically. A marriage can be so easily decoded and read so easily because some key part of human activity has an identifiable and stable pattern. Predicting divorce, like tracking Morse code operators, is pattern recognition.

Despite an overwhelming amount of information, Gottman has managed to simplify his predictions. Gottman is incredibly selective in the emotions that he pays attention to and has found that he finds out much of what he needs to know through careful attention to four key emotions he calls the Four Horsemen: defensiveness, stonewalling, criticism, and contempt – the most important of which is contempt. If Gottman observes either or both of the partners in a marriage showing contempt for one another, he considers it the single most important sign that the marriage is in trouble. Showing contempt for a loved one can be so stressful that it can affect the functioning of the immune system. Gottman has found that contempt is special, and that if it can be measured, then there is no need to know every detail of the couple’s relationship.

Gladwell further problematizes the view that more time spent gathering information leads to an overall better position in knowing something about a person. He gives the example of psychologist Samuel Gosling, who has shown that judging people’s personalities is a really good way of how surprisingly effective thin-slicing can be. Gosling experimented on eighty college students, and used the Big Five inventory, a multi-item questionnaire that measures people across five different dimensions: extraversion, agreeableness, conscientiousness, emotional stability, openness to new experiences. He asked the college students to fill it out, and then had the close friends of those students fill it out as well. He found that close friends, not surprisingly, could give an accurate portrayal of their friends’ personalities.

Gosling repeated the process, but used total strangers who had never met the students they were judging. The strangers were shown the students’ dorm rooms and were asked to rate the inhabitant of the room on a variety of scales: talkativeness, reserved personality, originality, etc. The dorm room observers were not nearly as good as friends in measuring extraversion or agreeableness. But when it came to conscientiousness, emotional stability, and openness to new experiences, they came out on top – suggesting that people who have never met a person, given a few minutes to think, can have a better understanding of who a person is than those who have known a person for years. Important is the information that one has when meeting a person (through interactions), but also important is the information not as easily accessible (such as a dorm room).

In Gladwell's third example, he presents a hypothetical situation in which an accountant in a medical malpractice insurance company is asked, who among all the physicians covered by the company is most likely to be sued. There are two options: the first is to examine the physicians’ training and credentials and analyze records to see how many errors they have made over the past few years. The second option is to listen to very brief snippets of conversation between each doctor and his or her patients. Gladwell states that risk of being sued for malpractice has little to do with how many mistakes a doctor makes – patients file lawsuits because they have been harmed by inadequate medical care and how they were treated, on a personal level, by their doctor. The recurrent theme in malpractice is that the patients say they were rushed or ignored or treated poorly. Studies on malpractice have also shown that in the end, it comes down to a matter of respect, and the simplest way respect is communicated is through tone of voice.


Gladwell says that thin-slicing is not a unique gift, that it is a central part of what it means to be human. Humans thin-slice when they meet a new person, or have to make sense of something quickly or encounter a new situation. People thin-slice because they have to, and they have come to rely on that ability because there are lots of situations where careful attention to the details of a thin slice can give a great deal of information.

A lot of what people say about their own personalities can also be very confusing, because most people are not very objective about themselves. Indirect questions are helpful in this way, and strangers are thus also able to make the predictions that Gottman and Gosling found in their research.

Expectations about people one has never met can be both dangerous and fruitful. So for those who were part of the dorm room study, it is useful to see how they make judgments based upon an initial exposure to another person's living space.

One of the possible inconsistencies in Gladwell's argument, one that sometimes arises in different parts of his book, is that of initial impressions. No doubt that Gottman and company are good at quickly figuring out the future of a couple, but to have gotten to that point required years of observation that has habituated and pruned them to think that way.

Systems like SPAFF require a great deal of investment of time and money, but the entire principle of SPAFF runs contrary to the types of initial snap judgments that Gladwell values greatly and emphasizes throughout his argument.