Ambady says that she and her colleagues were “totally stunned by the results,” and it’s not hard to understand why. The judges knew nothing about the skill level of the surgeons. They didn’t know how experienced they were, what kind of training they had, or what kind of procedures they tended to do. They didn’t even know what the doctors were saying to their patients. All they were using for their prediction was their analysis of the surgeon’s tone of voice. In fact, it was even more basic than that: if the surgeon’s voice was judged to sound dominant, the surgeon tended to be in the sued group. If the voice sounded less dominant and more concerned, the surgeon tended to be in the non-sued group. Could there be a thinner slice? Malpractice sounds like one of those infinitely complicated and multidimensional problems. But in the end it comes down to a matter of respect, and the simplest way that respect is communicated is through tone of voice, and the most corrosive tone of voice that a doctor can assume is a dominant tone. Did Ambady need to sample the entire history of a patient and doctor to pick up on that tone? No, because a medical consultation is a lot like one of Gottman’s conflict discussions or a student’s dorm room. It’s one of those situations where the signature comes through loud and clear.

Next time you meet a doctor, and you sit down in his office and he starts to talk, if you have the sense that he isn’t listening to you, that he’s talking down to you, and that he isn’t treating you with respect, listen to that feeling. You have thin-sliced him and found him wanting.

Thin-slicing is not an exotic gift. It is a central part of what it means to be human. We thin-slice whenever we meet a new person or have to make sense of something quickly or encounter a novel situation. We thin-slice because we have to, and we come to rely on that ability because there are lots of hidden fists out there, lots of situations where careful attention to the details of a very thin slice, even for no more than a second or two, can tell us an awful lot.

It is striking, for instance, how many different professions and disciplines have a word to describe the particular gift of reading deeply into the narrowest slivers of experience. In basketball, the player who can take in and comprehend all that is happening around him or her is said to have “court sense.” In the military, brilliant generals are said to possess “coup d’oeil”—which, translated from the French, means “power of the glance”: the ability to immediately see and make sense of the battlefield. Napoleon had coup d’oeil. So did Patton. The ornithologist David Sibley says that in Cape May, New Jersey, he once spotted a bird in flight from two hundred yards away and knew, instantly, that it was a ruff, a rare sandpiper. He had never seen a ruff in flight before; nor was the moment long enough for him to make a careful identification. But he was able to capture what bird-watchers call the bird’s “giss”—its essence—and that was enough.

“Most of bird identification is based on a sort of subjective impression—the way a bird moves and little instantaneous appearances at different angles and sequences of different appearances, and as it turns its head and as it flies and as it turns around, you see sequences of different shapes and angles,” Sibley says. “All that combines to create a unique impression of a bird that can’t really be taken apart and described in words. When it comes down to being in the field and looking at a bird, you don’t take the time to analyze it and say it shows this, this, and this; therefore it must be this species. It’s more natural and instinctive. After a lot of practice, you look at the bird, and it triggers little switches in your brain. It looks right. You know what it is at a glance.”

The Hollywood producer Brian Grazer, who has produced many of the biggest hit movies of the past twenty years, uses almost exactly the same language to describe the first time he met the actor Tom Hanks. It was in 1983. Hanks was then a virtual unknown. All he had done was the now (justly) forgotten TV show called Bosom Buddies. “He came in and read for the movie Splash, and right there, in the moment, I can tell you just what I saw,” Grazer says. In that first instant, he knew Hanks was special. “We read hundreds of people for that part, and other people were funnier than him. But they weren’t as likable as him. I felt like I could live inside of him. I felt like his problems were problems I could relate to. You know, in order to make somebody laugh, you have to be interesting, and in order to be interesting, you have to do things that are mean. Comedy comes out of anger, and interesting comes out of angry; otherwise there is no conflict. But he was able to be mean and you forgave him, and you have to be able to forgive somebody, because at the end of the day, you still have to be with him, even after he’s dumped the girl or made some choices that you don’t agree with. All of this wasn’t thought out in words at the time. It was an intuitive conclusion that only later I could deconstruct.”

My guess is that many of you have the same impression of Tom Hanks. If I asked you what he was like, you would say that he is decent and trustworthy and down-to-earth and funny. But you don’t know him. You’re not friends with him. You’ve only seen him in the movies, playing a wide range of different characters. Nonetheless, you’ve managed to extract something very meaningful about him from those thin slices of experience, and that impression has a powerful effect on how you experience Tom Hanks’s movies. “Everybody said that they couldn’t see Tom Hanks as an astronaut,” Grazer says of his decision to cast Hanks in the hit movie Apollo 13. “Well, I didn’t know whether Tom Hanks was an astronaut. But I saw this as a movie about a spacecraft in jeopardy. And who does the world want to get back the most? Who does America want to save? Tom Hanks. We don’t want to see him die. We like him too much.”

If we couldn’t thin-slice—if you really had to know someone for months and months to get at their true selves—then Apollo 13 would be robbed of its drama and Splash would not be funny. And if we could not make sense of complicated situations in a flash, basketball would be chaotic, and bird-watchers would be helpless. Not long ago, a group of psychologists reworked the divorce prediction test that I found so overwhelming. They took a number of Gottman’s couples videos and showed them to nonexperts—only this time, they provided the raters with a little help. They gave them a list of emotions to look for. They broke the tapes into thirty-second segments and allowed everyone to look at each segment twice, once to focus on the man and once to focus on the woman. And what happened? This time around, the observers’ ratings predicted with better than 80 percent accuracy which marriages were going to make it. That’s not quite as good as Gottman. But it’s pretty impressive—and that shouldn’t come as a surprise. We’re old hands at thin-slicing.