Subliminal: how your unconscious mind rules your behavior - Leonard Mlodinow 2013

Reading People
The Social Unconscious

Your amicable words mean nothing if your body seems to be saying something different. —JAMES BORG

IN THE LATE summer of 1904, just a few months before the start of Einstein’s “miracle year,” the New York Times reported on another German scientific miracle, a horse that “can do almost everything but talk.”¹ The story, the reporter assured us, was not drawn from the imagination but was based on the observations of a commission appointed by the Prussian minister of education, as well as the observations of the reporter himself. The subject of the article was described as a stallion, later dubbed Clever Hans, who could perform arithmetic and intellectual tasks on the level of those performed in one of today’s third-grade classrooms. Since Hans was nine that would have been appropriate for his age, if not his species. In fact, rather like the average human nine-year-old, Hans had by then received four years of formal instruction, homeschooled by his owner, a Herr Wilhelm von Osten. Von Osten, who taught math at a local gymnasium—something like a high school—had a reputation for being an old crank, and also for not caring if he was viewed that way. Every day at a certain hour von Osten stood before Hans—in full view of his neighbors—and instructed the horse by employing various props and a blackboard, then rewarded him with a carrot or a piece of sugar.

Hans learned to respond to his master’s questions by stamping his right hoof. The New York Times reporter described how, on one occasion, Hans was told to stamp once for gold, twice for silver, and three times for copper, and then correctly identified coins made from those metals. He identified colored hats in an analogous manner. Using the sign language of hoof taps, he could also tell time; identify the month and the day of the week; indicate the number of 4’s in 8, 16, and 32; add 5 and 9; and even indicate the remainder when 7 was divided by 3. By the time the reporter witnessed this display, Hans had become something of a celebrity. Von Osten had been exhibiting him at gatherings throughout Germany—even at a command performance before the kaiser himself—and he never charged admission, because he was trying to convince the public of the potential for humanlike intelligence in animals. So much interest was there in the phenomenon of the high-IQ horse that a commission had been convened to assess von Osten’s claims, and it concluded that no trickery was involved in Hans’s feats. According to the statement issued by the commission, the explanation for the horse’s ability lay in the superior teaching methods employed by von Osten—methods that corresponded to those employed in Prussia’s own elementary schools. It’s not clear if the “superior teaching methods” referred to the sugar or the carrots, but according to one commission member, the director of the Prussian Natural History Museum, “Herr von Osten has succeeded in training Hans by cultivating in him a desire for delicacies.” He added, “I doubt whether the horse really takes pleasure in his studies.” Even more evidence, I suppose, of Hans’s startling humanity.

But not everyone was convinced by the commission’s conclusions. One telling indication that there might be more to Hans’s feats than an advance in equine teaching methodology was that Hans could sometimes answer von Osten’s questions even if von Osten didn’t verbalize them. That is, von Osten’s horse seemed to be able to read his mind. A psychologist named Oskar Pfungst decided to investigate. With von Osten’s encouragement, Pfungst conducted a series of experiments. He discovered that the horse could answer questions posed by people other than von Osten, but only if the questioners knew the answer, and only if they were visible to Hans during the hoof tapping.

It required a series of additional careful experiments, but Pfungst eventually found that the key to the horse’s intellectual feats lay in involuntary and unconscious cues displayed by the questioner. As soon as a problem was posed, Pfungst discovered, the questioner would involuntarily and almost imperceptibly bend forward, which prompted Hans to begin tapping. Then, as the correct answer was reached, another slight bit of body language would signal Hans to stop. It was a “tell,” as the poker crowd calls it, an unconscious change of demeanor that broadcasts a clue to a person’s state of mind. Every one of the horse’s questioners, Pfungst noted, made similar “minimal muscular movements” without being aware of doing so. Hans might not have been a racehorse, but he had the heart of a poker player.

In the end Pfungst demonstrated his theory with a flourish by playing the role of Hans and enlisting twenty-five experimental subjects to question him. None were aware of the precise purpose of the experiment, but all were aware they were being observed for clues that might give the answer away. Twenty-three of the twenty-five made such movements anyway, though all denied having done so. Von Osten, for the record, refused to accept Pfungst’s conclusions and continued to tour Germany with Hans, drawing large and enthusiastic crowds.

As anyone who has ever been on the receiving end of a fellow driver’s display of the middle finger knows, nonverbal communication is sometimes quite obvious and conscious. But then there are those times when a significant other says, “Don’t look at me like that,” and you respond, “Don’t look at you like what?,” knowing full well the nature of the feelings you were so sure you had hidden. Or you might smack your lips and proclaim that your spouse’s scallop-and-cheddar casserole is yummy but somehow still elicit the response “What, you don’t like it?” Don’t fret; if a horse can read you, why not your spouse?

Scientists attach great importance to the human capacity for spoken language. But we also have a parallel track of nonverbal communication, and those messages may reveal more than our carefully chosen words and sometimes be at odds with them. Since much, if not most, of the nonverbal signaling and reading of signals is automatic and performed outside our conscious awareness and control, through our nonverbal cues we unwittingly communicate a great deal of information about ourselves and our state of mind. The gestures we make, the position in which we hold our bodies, the expressions we wear on our faces, and the nonverbal qualities of our speech—all contribute to how others view us.

THE POWER OF nonverbal cues is particularly evident in our relationship with animals because, unless you live in a Pixar movie, nonhuman species have a limited understanding of human speech. Like Hans, though, many animals are sensitive to human gestures and body language.² One recent study, for example, found that when trained properly, a wolf can be a decent acquaintance and respond to a human’s nonverbal signals.³ Though you wouldn’t want to name a wolf Fido and leave it to play with your one-year-old, wolves are actually very social animals, and one reason they can respond to nonverbal cues from humans is that they have a rich repertoire of such signals within their own community. Wolves engage in a number of cooperative behaviors that require skill in predicting and interpreting the body language of their peers. So if you’re a wolf, you know that when a fellow wolf holds its ears erect and forward and its tail vertical, it is signaling dominance. If it pulls its ears back and narrows its eyes, it is suspicious. If it flattens its ears against its head and tucks its tail between its legs, it is fearful. Wolves haven’t been explicitly tested, but their behavior seems to imply that they are capable of at least some degree of ToM. Still, wolves are not man’s best friend. Instead it is the dog, which originated from wolves, that is best at reading human social signals. At that task, dogs appear even more skilled than our primate relatives. That finding surprised a lot of people because primates are far superior at other typical human endeavors, like problem solving and cheating.⁴ This suggests that during the process of domestication, evolution favored those dogs who developed mental adaptations allowing them to be better companions to our species⁵—and hence to avail themselves of the benefits of home and hearth.

One of the most revealing studies of human nonverbal communication was performed using an animal with which humans rarely share their homes, at least not intentionally: the rat. In that study, students in an experimental psychology class were each given five of those creatures, a T-shaped maze, and a seemingly simple assignment.⁶ One arm of the T was colored white, the other gray. Each rat’s job was to learn to run to the gray side, at which time it would be rewarded with food. The students’ job was to give each rat ten chances each day to learn that the gray side of the maze was the one that led to food and to objectively record each rat’s learning progress, if any. But it was actually the students, not the rats, who were the guinea pigs in this experiment. The students were informed that through careful breeding it was possible to create strains of maze-genius and maze-dummy rats. Half the students were told that their rats were the Vasco da Gamas of maze explorers, while the other half were told that theirs had been bred to have no sense of direction at all. In reality, no such selective breeding had been performed, and the animals were effectively interchangeable, except perhaps to their mothers. The real point of the experiment was to compare the results obtained by the two distinct groups of humans, to see if their expectations would bias the results achieved by their rats.

The researchers found that the rats the students thought were brilliant performed significantly better than the rats believed to be on the dumb side. The researchers then asked each student to describe his or her behavior toward the rats, and an analysis showed differences in the manner in which students in each group related to the animals. For example, judging from their reports, those who believed their rats to be high achievers handled them more and were gentler, thereby communicating their attitude. Of course, that might have been intentional, and the cues we are interested in are those that are unintentional and difficult to control. Luckily, another pair of researchers shared that curiosity.⁷ They essentially repeated the experiment but added an admonishment to the students that a key part of their task was to treat each rat as they would if they had no prior knowledge about its breeding. Differences in handling, they were warned, could skew the results and, by implication, their grade. Despite these caveats, the researchers also found superior performance among the rats whose handlers expected it. The students attempted to act impartially, but they couldn’t. They unconsciously delivered cues, based on their expectations, and the rats responded.

It’s easy to draw analogies with how unconsciously communicated expectations might also affect human performance, but are they accurate? One of the researchers in the rat study, Robert Rosenthal, decided to find out.⁸ His plan was to again have his students conduct an experiment, but this time they would experiment on people, not rats. That, of course, involved altering the experiment to be better suited to human subjects. Rosenthal came up with this: he asked the student experimenters—who were themselves the true subjects of the experiment—to show their subjects photographs of people’s faces and request that they rate each face on the degree of success or failure they felt it reflected. Rosenthal had pretested a large set of photos, and he gave his students only those photos that had been judged as neutral. But that’s not what he told them. He said he was trying to duplicate an experiment that had already been performed, and he told half the experimenters that their stack of photos depicted faces that had been rated as successful, and the other half that theirs were rated as failures.

In order to make sure the student experimenters did not use any verbal language to communicate their expectations, Rosenthal gave them all a written script to follow and warned them not to deviate from it in any way or speak any other words. Their job was merely to present the photos to their subjects, read the instructions, and record their subjects’ responses. One could hardly take stronger precautions to discourage experimenter bias. But would their nonverbal communication nevertheless flag their expectations? Would the human subjects respond to these cues just as the rats had done?

Not only, on average, did the students who expected their subjects to accord high success ratings to the photos obtain such ratings but, in addition, every single student who had been led to expect high ratings obtained higher ratings from their subjects than did any of those expecting low ratings. Somehow they were subliminally communicating their expectations. But how?

A year later, another set of researchers repeated Rosenthal’s study, with a twist.⁹ During the course of that study, they recorded the experimenters’ instructions to their subjects. Then they conducted another experiment, in which they eliminated the human experimenters and instead communicated the instructions to the subjects using the tape recordings, thus getting rid of all cues other than those that could be transmitted through the sound of the voice. Again the results were biased, but only about half as much. So one important way the experimenters’ expectations were communicated was through the inflection and tonal quality of their voices. But if that is just half the story, what’s the other half? No one knows for sure. Over the years, many scientists have tried to find out by doing variants of the experiment, but though they confirmed the effect, none was ever able to specify any more precisely just what the other nonverbal signals were. Whatever they were, they were subtle and unconscious and probably varied considerably among the individuals.

The lesson learned has obvious applications in our personal and professional lives, with regard to our family, our friends, our employees, our employers and even the subjects being interviewed in a marketing focus group: whether or not we wish to, we communicate our expectations to others, and they often respond by fulfilling those expectations. You can probably think of expectations, whether stated or not, that you have regarding most people you interact with. And they have expectations of you. That’s one of the gifts I received from my parents: to be treated like the Vasco da Gama rats, to be made to feel as if I could navigate my way to success in whatever I set out to do. It’s not that my parents talked to me about their belief in me, but I somehow felt it, and it has always been a source of strength.

Rosenthal went on to study precisely that—what expectations mean for our children.¹⁰ In one line of research he showed that teachers’ expectations greatly affect their students’ academic performance, even when the teachers try to treat them impartially. For example, he and a colleague asked schoolkids in eighteen classrooms to complete an IQ test. The teachers, but not the students, were given the results. The researchers told the teachers that the test would indicate which children had unusually high intellectual potential.¹¹ What the teachers didn’t know was that the kids named as gifted did not really score higher than average on the IQ test—they actually had average scores. Shortly afterward, the teachers rated those not labeled gifted as less curious and less interested than the gifted students—and the students’ subsequent grades reflected that.

But what is really shocking—and sobering—is the result of another IQ test, given eight months later. When you administer an IQ test a second time, you expect that each child’s score will vary some. In general, about half of the children’s scores should go up and half down, as a result of changes in the individual’s intellectual development in relation to his peers or simply of random variation. When Rosenthal administered the second test, he indeed found that about half the kids labeled “normal” showed a gain in IQ. But among those who’d been singled out as brilliant, he obtained a different result: about 80 percent had an increase of at least 10 points. What’s more, about 20 percent of the “gifted” group gained 30 or more IQ points, while only 5 percent of the other children gained that many. Labeling children as gifted had proved to be a powerful self-fulfilling prophecy. Wisely, Rosenthal hadn’t falsely labeled any kids as being below average. The sad thing is that such labeling does happen, and it is reasonable to assume that the self-fulfilling prophecy also works the other way: that branding a child a poor learner will contribute to making the child exactly that.

HUMANS COMMUNICATE VIA a rich linguistic system whose development was a defining moment in the evolution of our species, an innovation that remade the character of human society. It’s an ability that seems to be unique.¹² In other animals, communication is limited to simple messages, such as identifying themselves or issuing warnings; there is little complex structure. Had Hans, for example, been required to answer in complete sentences, the gig would have been up. Even among primates, no species naturally acquires more than a few signals or combines them in anything but a rudimentary manner. The average human, on the other hand, is familiar with tens of thousands of words and can string them together according to complex rules, with hardly any conscious effort, and without formal instruction.

Scientists don’t understand yet how language evolved. Many believe that earlier human species, such as Homo habilis and Homo erectus, possessed primitive language-like or symbolic communication systems. But the development of language as we know it probably didn’t occur until modern humans came into the picture. Some say language originated one hundred thousand years ago, some later; but the need for sophisticated communication certainly became more urgent once “behaviorally modern” social humans developed, fifty thousand years ago. We’ve seen how important social interactions are to our species, and social interactions go hand in hand with the need to communicate. That need is so powerful that even deaf babies develop language-like gesture systems and, if taught sign language, will babble using their hands.¹³

Why did humans develop nonverbal communication? One of the first to seriously study the issue was an English fellow, spurred by his interest in the theory of evolution. By his own assessment, he was no genius. He had “no great quickness of apprehension or wit” or “power to follow a long and purely abstract train of thought.”¹⁴ On the many occasions when I share those feelings, I find it encouraging to review those words because that Englishman did okay for himself—his name was Charles Darwin. Thirteen years after publishing The Origin of Species, Darwin published another radical book, this one called The Expression of the Emotions in Man and Animals. In it, Darwin argued that emotions—and the ways they are expressed—provide a survival advantage and that they are not unique to humans but occur in many species. Clues to the role of emotions therefore can be found by examining the similarities and differences of nonverbal emotional expression across various species.

If Darwin didn’t consider himself brilliant, he did believe he possessed one great intellectual strength: his powers of careful and detailed observation. And, indeed, though he was not the first to suggest the universality of emotion and its expression,¹⁵ he spent several decades meticulously studying the physical manifestations of mental states. He watched his countrymen, and he observed foreigners, too, looking for cultural similarities and differences. He even studied domestic animals and those in the London Zoo. In his book, Darwin categorized numerous human expressions and gestures of emotion and offered hypotheses about their origin. He noted how lower animals, too, display intent and emotion through facial expression, posture, and gesture. Darwin speculated that much of our nonverbal communication might be an innate and automatic holdover from earlier phases of our evolution. For example, we can bite affectionately, as do other animals. We also sneer like other primates by flaring our nostrils and baring our teeth.

The smile is another expression we share with lower primates. Suppose you’re sitting in some public place and notice someone looking at you. If you return the gaze and the other person smiles, you’ll probably feel good about the exchange. But if the other person continues to stare without any hint of a smile, you’ll probably feel uncomfortable. Where do these instinctual responses come from? In trading the currency of smiles, we are sharing a feeling experienced by many of our primate cousins. In the societies of nonhuman primates, a direct stare is an aggressive signal. It often precedes an attack—and, therefore, can precipitate one. As a result, if, say, a submissive monkey wants to check out a dominant one, it will bare its teeth as a peace signal. In monkey talk, bared teeth means Pardon my stare. True, I’m looking, but I don’t plan to attack, so PLEASE don’t attack me first. In chimpanzees, the smile can also go the other way—a dominant individual may smile at a submissive one, saying, analogously, Don’t worry, I’m not going to attack you. So when you pass a stranger in the corridor and that person flashes a brief smile, you’re experiencing an exchange with roots deep in our primate heritage. There is even evidence that with chimps, as with humans, when a smile is exchanged, it can be a sign of friendship.¹⁶

You might think a smile is a rather shoddy barometer of true feelings because, after all, anyone can fake one. It’s true that we can consciously decide to exhibit a smile, or any other expression, by using the muscles in our faces in ways we are practiced at doing. Think about what you do when trying to make a good impression at a cocktail party, even though you are miserable about being there. But our facial expressions are also governed subliminally, by muscles over which we have no conscious control. So our real expressions cannot be faked. Sure, anyone can create a posed smile by contracting the zygomatic major muscles, which pull the corners of the mouth up toward the cheekbones. But a genuine smile involves contraction of an additional pair of actors, the orbicularis oculi muscles, which pull the skin surrounding the eye toward the eyeball, causing an effect that looks like crow’s-feet but can be very subtle. That was first pointed out by the nineteenth-century French neurologist Duchenne de Boulogne, who was an influence on Darwin and collected a large number of photographs of people smiling. There are two distinct neural pathways for these smile muscles: a voluntary one for the zygomatic major, and an involuntary one for the orbicularis oculi.¹⁷ So a smile-seeking photographer might implore us to say “cheese,” which nudges our mouths into the smile position, but unless you’re the kind who actually rejoices when asked to speak the word “cheese,” the smile won’t look genuine.

In viewing photographs of the two types of smiles given to him by Duchenne de Boulogne, Darwin remarked that though people could sense the difference, he found it very difficult to consciously pinpoint what that difference was, remarking, “It has often struck me as a curious fact that so many shades of expression are instantly recognized without any conscious process of analysis on our part.”¹⁸ No one paid much attention to such issues until recently, but modern studies have shown that, as Darwin observed, even people untrained in smile analysis have a good enough gut feeling to distinguish real smiles from phony ones when they can observe the same individual creating both.¹⁹ Smiles we intuitively recognize as fake are one reason used-car salesmen, politicians, and others who smile when they don’t mean it are often described as looking sleazy. Actors in the Method dramatic tradition try to get around this by training themselves to actually feel the emotion they are supposed to manifest, and many successful politicians are said to be talented at conjuring up genuine feelings of friendliness and empathy when talking to a roomful of strangers.

Darwin realized that if our expressions evolved along with our species, then many of the ways we express the basic emotions—happiness, fear, anger, disgust, sadness, and surprise—should be shared by humans from different cultures. And so in 1867 he arranged for a questionnaire to be circulated on five continents among indigenous people, some of whom had had little contact with Europeans.²⁰ The survey asked questions like “Is astonishment expressed by the eyes and mouth being opened wide and by the eyebrows being raised?” On the basis of the answers he received, Darwin concluded that “the same state of mind is expressed throughout the world with remarkable uniformity.” Darwin’s study was biased in that his questionnaire asked such leading questions, and like so many other early contributions to psychology, his were overridden—in this case, by the idea that facial expressions are learned behavior, acquired during infancy, as a baby mimics its caretakers and others in the immediate environment. However, in recent years a substantial body of cross-cultural research has offered evidence that Darwin was right after all.²¹

In the first of a series of famous studies, the psychologist Paul Ekman showed photos of people’s expressions to subjects in Chile, Argentina, Brazil, the United States, and Japan.²² Within a few years, he and a colleague had shown such pictures to people in twenty-one countries. Their findings were the same as Darwin’s, demonstrating that people across a diversity of cultures had a similar understanding of the emotional meaning of a range of facial expressions. Still, such studies alone don’t necessarily mean that those expressions are innate, or even truly universal. Adherents of the “learned expressions” theory argued that Ekman’s results conveyed no deeper truth than the fact that people in the societies studied had all watched Gilligan’s Island, or other movies and television shows. So Ekman traveled to New Guinea, where an isolated Neolithic culture had recently been discovered.²³ The natives there had no written language and were still using stone implements. Very few had seen a photograph, much less film or television. Ekman recruited hundreds of these subjects, who had never been previously exposed to outside cultures, and, through a translator, presented them with photographs of American faces illustrating the basic emotions.

The primitive foragers proved to be as nimble as those in the twenty-one literate countries at recognizing happiness, fear, anger, disgust, sadness, and surprise in the face of an emoting American. The scientists also reversed the research design. They photographed the New Guineans as they acted out how they would respond if they saw that their child had died, or found a dead pig that had been lying there for a long time, and so on. The expressions Ekman recorded were unequivocally recognizable.²⁴

This universal capability to create and recognize facial expressions starts at or near birth. Young infants have been observed making nearly all the same facial muscle movements used by adults to signify emotion. Infants can also discriminate among the facial expressions of others and, like adults, modify their behavior based on what they see.²⁵ It is doubtful that these are learned behaviors. In fact, congenitally blind young children, who have never seen a frown or a smile, express a range of spontaneous facial emotions that are almost identical to those of the sighted.²⁶ Our catalog of facial expressions seems to be standard equipment—it comes with the basic model. And because it is a largely innate, unconscious part of our being, communicating our feelings comes naturally, while hiding them requires great effort.

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IN HUMANS, BODY language and nonverbal communication are not limited to simple gestures and expressions. We have a highly complex system of nonverbal language, and we routinely participate in elaborate nonverbal exchanges, even when we are not consciously aware of doing so. For example, in the case of casual contact with the opposite sex, I’d have been willing to bet a year’s pass to a Manhattan cinema that if a male pollster type approached a guy’s date while they were standing in line to buy a ticket at said theater, few of the fellows approached would be so insecure that they’d consciously feel threatened by the pollster. And yet, consider this experiment, conducted over two mild autumn weekend evenings in an “upper-middle-class” neighborhood in Manhattan.²⁷ The subjects approached were all couples, yes, waiting in line to buy tickets to a movie.

The experimenters worked in teams of two. One team member discreetly observed from a short distance while the other approached the female of the couple and asked if she would be willing to answer a few survey questions. Some of the women were asked neutral questions, such as “What is your favorite city and why?” Others were asked personal questions, such as “What is your most embarrassing childhood memory?” The researchers expected these more personal questions to be more threatening to the boyfriend, more invasive to his sense of intimate space. How did the boyfriends respond?

Unlike the male hamadryas baboon, who starts a fight when he sees another male sitting too close to a female in his group,²⁸ the boyfriends didn’t do anything overtly aggressive; but they did display certain nonverbal cues. The scientists found that when the interviewer was nonthreatening—either a male who asked impersonal questions or a female—the man in the couple tended to just hang out. But when the interviewer was a male asking personal questions, the boyfriend would subtly inject himself into the powwow, flashing what are called “tie-signs,” nonverbal cues meant to convey a connection with the woman. These male smoke signals included orienting himself toward his partner and looking into her eyes as she interacted with the other man. It is doubtful that the men consciously felt the need to defend their relationship from the polite interviewer, but even though the tie-signs fell short of a baboonlike fist in the face, they were an indication of the men’s inner primate pushing its way to the fore.

Another, more complex mode of nonverbal “conversation” has to do with dominance. Nonhuman primates actually maintain fine distinctions along that dimension; they have precise dominance hierarchies, something like the ranks in the army. Without the pretty insignias, though, one might wonder how a chimp knows whom to salute. Dominant primates pound their chests and use voice and other signals to indicate their high rank. One way a chimp can signal its acknowledgment that it is lower in rank, as I said, is to smile. Another is to turn around, bend over, and moon its superior. Yes, that particular behavior, though still practiced by humans, seems to have changed its meaning somewhere along the road of evolution.

In modern human society, there are two kinds of dominance.²⁹ One is physical dominance, based on aggression or the threat of aggression. Physical dominance in humans is similar to dominance in nonhuman primates, though we signal it differently: it is the rare chimpanzee who announces his dominance, as some humans do, by carrying around a switchblade or a .357 Magnum, or by wearing a tight muscle shirt. Humans, however, can also achieve another kind of dominance: social dominance.

Social dominance is based on admiration rather than fear and is acquired through social accomplishment rather than physical prowess. Signals of social dominance—like wearing a Rolex or driving a Lamborghini—can be just as clear and overt as the chest-pounding a male baboon might display. But they can also be subtle, such as declining any conspicuous display of affluence by showing up unexpectedly in torn, faded nondesigner jeans and an old Gap T-shirt, or by refusing to wear anything with a logo on it. (Take that, you silly Prada and Louis Vuitton bag toters!)

Humans have many ways indeed of signaling “I’m the general and you’re not” without mooning or wearing a shoulder patch with stars on it. As in other primate societies, gaze direction and stare are important signals of dominance in human society.³⁰ For example, if a child looks away while the parent is scolding, the adult might say, “Look at me while I’m talking to you!” I’ve said that myself on occasion, though since you don’t hear with your eyes, the demand seems to serve no functional purpose. The interaction is really about the parent’s demand for respect—or in primate language, dominance. What the adult is really saying is Stand at attention. Salute. I am dominant, so when I speak, you must look at me!

We may not realize it, but we don’t just play the gaze game with our children; we play it with our friends and acquaintances, our superiors and subordinates, when we speak to a queen or a president, to a gardener or a store clerk, or to strangers we meet at a party. We automatically adjust the amount of time we spend looking into another’s eyes as a function of our relative social position, and we typically do it without being aware that we are doing it.³¹ That might sound counterintuitive, because some people like to look everyone in the eye, while others tend to always look elsewhere, whether they are speaking to a CEO or the guy dropping a pack of chicken thighs into their bag at the local grocery store. So how can gazing behavior be related to social dominance?

It is not your overall tendency to look at someone that is telling but the way in which you adjust your behavior when you switch between the roles of listener and speaker. Psychologists have been able to characterize that behavior with a single quantitative measure, and the data they produce using that measure is striking.

Here is how it works: take the percentage of time you spend looking into someone’s eyes while you are speaking and divide it by the percentage spent looking at that same person’s eyes while you are listening. For example, if, no matter which of you is talking, you spend the same amount of time looking away, your ratio would be 1.0. But if you tend to look away more often while you are speaking than when you are listening, your ratio will be less than 1.0. If you tend to look away less often when you are speaking than when you are listening, you have a ratio higher than 1.0. That quotient, psychologists discovered, is a revealing statistic. It is called the “visual dominance ratio,” and it reflects your position on the social dominance hierarchy relative to your conversational partner. A visual dominance ratio near 1.0, or larger, is characteristic of people with relatively high social dominance. A visual dominance ratio less than 1.0 is indicative of being lower on the dominance hierarchy. In other words, if your visual dominance ratio is around 1.0 or higher, you are probably the boss; if it is around 0.6, you are probably the bossed.

The unconscious mind provides us with many wonderful services and performs many awesome feats, but I can’t help being impressed by this one. What is so striking about the data is not just that we subliminally adjust our gazing behavior to match our place on the hierarchy but that we do it so consistently, and with numerical precision. Here is a sample of the data: when speaking to each other, ROTC officers exhibited ratios of 1.06, while ROTC cadets speaking to officers had ratios of 0.61;³² undergraduates in an introductory psychology course scored 0.92 when talking to a person they believed to be a high school senior who did not plan to go to college but 0.59 when talking to a person they believed to be a college chemistry honor student accepted into a prestigious medical school;³³ expert men speaking to women about a subject in their own field scored 0.98, while men talking to expert women about the women’s field, 0.61; expert women speaking to nonexpert men scored 1.04, and nonexpert women speaking to expert men scored 0.54.³⁴ These studies were all performed on Americans. The numbers probably vary among cultures, but the phenomenon probably doesn’t.

Whatever your culture, since people unconsciously detect these signals, it stands to reason that one can also adjust the impression one makes by consciously looking at or away from a conversational partner. For example, when applying for a job, talking to your boss, or negotiating a business deal, it might be advantageous to signal a certain level of submission—but how much would depend on the circumstances. In a job interview, if the job requires great leadership ability, a display of too much submissiveness would be a bad strategy. But if the interviewer seemed very insecure, a pleasing display of just the right amount of submissiveness could be reassuring and incline that person in the applicant’s favor. A highly successful Hollywood agent once mentioned to me that he made a point to negotiate only over the telephone so as to avoid being influenced—or inadvertently revealing anything—through eye contact with the opposite party.

My father learned both the power and the danger of a simple look when he was imprisoned in the Buchenwald concentration camp. Weighing under a hundred pounds, he was then little more than a walking corpse. In the camp, if you were not being spoken to, locking eyes with one of your captors could spur rage. Lower forms were not supposed to make uninvited eye contact with the master race. Sometimes when I think in terms of the dichotomy between humans and “lower primates,” I remember my father’s experience, and the thin margin of extra frontal lobe that distinguishes civilized human from brute animal. If the purpose of that extra brain matter is to elevate us, it sometimes fails. But my father also told me that with certain guards, the right kind of eye contact could bring a word, a conversation, even a minor kindness. He said that when that happened it was because the eye contact raised him to the status of being human. But I think that by eliciting a human response from a guard, what his eye contact really did was raise the level of humanity of his captor.

TODAY MOST HUMANS live in large, crowded cities. In many cities, a single neighborhood could encompass the entire world population at the time of the great human social transformation. We walk down sidewalks and through crowded malls and buildings with hardly a word, and no traffic signs, and yet we don’t bump into others or get into fights about who is going to step through the swinging door first. We hold conversations with people we don’t know or hardly know or wouldn’t want to know and automatically stand at a distance that is acceptable to both of us. That distance varies from culture to culture and from individual to individual, and yet, without a word, and usually without giving it any thought, we adjust to a distance of mutual comfort. (Or most of us do, anyway. We can all think of exceptions!) When we talk, we automatically sense when it is time to leave a pause for others to jump in. As we’re about to yield the floor, we typically lower our volume, stretch out our last word, cease gesturing, and look at the other person.³⁵ Along with ToM, these skills aided our survival as a species, and it is still these skills that allow us to maneuver through the complex social world of the human.

Nonverbal communication forms a social language that is in many ways richer and more fundamental than our words. Our nonverbal sensors are so powerful that just the movements associated with body language—that is, minus the actual bodies—are enough to engender within us the ability to accurately perceive emotion. For example, researchers made video clips of participants who had about a dozen small lights or illuminated patches attached at certain key positions on their bodies, as in the picture here.³⁶ The videos were shot in light so dim that only the patches were visible. In these studies, when the participants stood still, the patches gave the impression of a meaningless collection of points. But when the participants stirred, observers were able to decode a surprising amount of information from the moving lights. They were able to judge the participants’ sex, and even the identity of people with whom they were familiar, from their gait alone. And when the participants were actors, mimes, or dancers asked to move in a way that expressed the basic emotions, the observers had no trouble detecting the emotion portrayed.

Courtesy of A. P. Atkinson. From A. P. Atkinson et al., “Emotion Perception from Dynamic and Static Body Expressions in Point-Light and Full-Light Displays,” Perception 33, 724. Copyright 2004.

By the time children reach school age, there are some with full social calendars, while others spend their days shooting spitballs at the ceiling. One of the major factors in social success, even at an early age, is a child’s sense of nonverbal cues. For example, in a study of sixty kindergartners, the children were asked to identify which of their classmates they’d prefer to sit with at storytime, play a game with, or work with on a painting. The same children were judged on their ability to name the emotions exhibited in twelve photographs of adults and children with differing facial expressions. The two measures proved to be related. That is, the researchers found a strong correlation between a child’s popularity and his or her ability to read others.³⁷

In adults, nonverbal ability bestows advantages in both personal and business life and plays a significant role in the perception of a person’s warmth,³⁸ credibility,³⁹ and persuasive power.⁴⁰ Your uncle Stu might be the kindest man in the world, but if he tends to speak at length on subjects like the moss he observed in Costa Rica and never notices the moss beginning to grow on his listeners’ faces, he’s probably not the most popular guy to hang out with. Our sensitivity to other people’s signals regarding their thoughts and moods helps make social situations proceed smoothly, with a minimum of conflict. From early childhood on, those who are good at giving and receiving signals have an easier time forming social structures and achieving their goals in social situations.

In the early 1950s, many linguists, anthropologists, and psychiatrists attempted to classify nonverbal cues in much the same way we classify verbal language. One anthropologist even developed a transcription system, providing a symbol for virtually every possible human movement so that gestures could be written down like speech.⁴¹ Today social psychologists sometimes categorize our nonverbal communication into three basic types. One category concerns body movements: facial expression, gestures, posture, eye movements. Another is called paralanguage, which includes the quality and pitch of your voice, the number and duration of pauses, and nonverbal sounds such as clearing one’s throat or saying “uh.” And finally, there is proxemics, the use of personal space.

Many popular books claim to provide guides to the interpretation of these factors and advise how you can employ them to your benefit. They tell you that tensely folded arms mean you are closed to what someone is telling you, while if you like what you hear, you’ll probably adopt an open posture, maybe even lean forward a little. They’ll say that moving your shoulders forward signifies disgust, despair, or fear, and that maintaining a large interpersonal distance while you speak signals low social stature.⁴² There haven’t been a lot of studies on the efficacy of the hundred and one ways these books tell you to act, but it’s probably true that assuming those different postures can have at least a subtle effect on how people perceive you, and that understanding what nonverbal cues mean can bring to your consciousness clues about people that otherwise only your unconscious might pick up. Yet even without a conscious understanding, you are a storehouse of information about nonverbal cues. The next time you view a film in a language you don’t know, try blocking out the subtitles. You’ll be surprised by how much of the story you can comprehend without a single word to communicate what is happening.