The Magic of Smiles and Laughter

Overview

The smile is one of the world's most irresistible signals — and one of the most misread. The opening anecdote makes the point: a man crosses a room because a woman keeps "smiling" at him, never realizing that her tight-lipped, no-teeth smile is a rejection signal his female friends read instantly. Grandmothers who told children to "put on a happy face" were right on an intuitive level, but the mechanism runs deeper than courtesy.

This topic traces smiling back to its evolutionary root as a primate submission signal, then equips the reader to decode it. The first scientific studies, by Guillaume Duchenne de Boulogne in the early nineteenth century, distinguished the smile of real enjoyment from every other kind by isolating two muscle groups: the consciously controlled zygomatic majors that pull the mouth, and the orbicularis oculi around the eyes that fire only with genuine feeling. From there the topic covers why smiling is contagious, how the brain decodes it as a survival aid, the counter-intuitive finding that liars smile less, the five common smile types and what each one means, and the second half of the chapter — laughter — as medicine, as a bonding tool, and as a courtship signal that differs sharply between men and women.

Key takeaways

Mental model

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The anatomy of a smile — two muscle groups

Duchenne's discovery

The first recorded scientific studies into smiling came in the early nineteenth century, when the French scientist Guillaume Duchenne de Boulogne used electrodiagnostics and electrical stimulation to distinguish the smile of real enjoyment from every other kind. Working on the heads of people executed by guillotine, he pulled the face muscles from many angles to catalog which muscles produced which smiles. He found that smiles are controlled by two sets of muscles:

• The zygomatic majors, which run down the side of the face and connect to the corners of the mouth. They pull the mouth back to expose the teeth and enlarge the cheeks. Crucially, they are consciously controlled — which means they are used to manufacture false smiles to appear friendly or subordinate.
• The orbicularis oculi, which pull the eyes back, narrow them, and cause "crow's feet." These act independently of conscious control and reveal the true feelings of a genuine smile.

Author's argument: A natural smile produces characteristic wrinkles around the eyes — insincere people smile only with their mouth. The first place to check the sincerity of any smile is to look for wrinkle lines beside the eyes.

Genuine versus fake — the markers

In the enjoyment smile, the lip corners pull up and the muscles around the eyes contract; in the non-enjoyment smile, only the lips move. Scientists formalized this with the Facial Action Coding System (FACS), devised by Professor Paul Ekman of the University of California and Dr. Wallace V. Friesen of the University of Kentucky. Genuine smiles are generated by the unconscious brain and are therefore automatic: when you feel pleasure, signals pass through the emotion-processing part of the brain, your mouth muscles move, your cheeks rise, your eyes crease, and your eyebrows dip slightly.

This is also why photographers who ask you to say "cheese" produce insincere photographs — the word pulls back the zygomatic majors but engages nothing around the eyes. Intense fake smiles can be tricky, because the cheeks may bunch up and make it look as if the eyes are contracting. The reliable tell: in a genuine smile, the fleshy eye-cover fold between the eyebrow and the eyelid moves downward and the ends of the eyebrows dip slightly.

Smiling is a submission signal

The primate root

Smiling and laughing are universally read as signs of happiness. We cry at birth, begin smiling at five weeks, and start laughing between the fourth and fifth months; babies learn that crying gets attention and smiling keeps it. But research with chimpanzees reveals a deeper, more primitive purpose.

To signal aggression, apes bare their lower fangs as a warning that they can bite — and humans do the same, dropping or thrusting the lower lip forward, since its main function is to sheath the lower teeth. Chimpanzees have two types of smiles, and both are submission gestures:

• The "fear face" (appeasement face): the lower jaw opens to expose the teeth and the corners of the mouth pull back and down. It communicates, "I am not a threat because, as you can see, I'm fearful of you." This is the same nervous smile a person makes after almost being hit by a bus.
• The "play face": the teeth are exposed, the corners of the mouth and eyes draw upward, and vocal sounds are made — much like human laughing. It says, "I am not a threat because, as you can see, I'm just like a playful child."

Why dominant people don't smile

In humans, smiling serves the same purpose: it tells another person you are nonthreatening and asks them to accept you personally. This explains why many dominant individuals — the author names Vladimir Putin, James Cagney, Clint Eastwood, Margaret Thatcher, and Charles Bronson — rarely smile and tend to look grumpy or aggressive. They simply do not want to appear submissive. Research in courtrooms even shows that an apology offered with a smile incurs a lesser penalty than one without — so Grandma was right.

Why smiling is contagious

The remarkable thing about a smile is that giving one to someone causes them to return it, even when both smiles are fake. Professor Ulf Dimberg at Uppsala University in Sweden measured the facial-muscle activity of 120 volunteers shown pictures of happy and angry faces and told to respond with the opposite expression. The volunteers could not fully control their muscles: frowning back at an angry face was easy, but smiling at it was difficult — their muscles twitched into mirroring the expression they saw, even when they consciously tried not to.

Professor Ruth Campbell of University College, London, attributes this to a "mirror neuron" in the brain that triggers face-and-expression recognition and causes an instant mirroring reaction — we automatically copy the expressions we see. The practical implication: regular smiling belongs in your body-language repertoire even when you do not feel like it, because it directly shapes others' attitudes and responses. In over thirty years studying sales and negotiation, the authors found that well-timed smiling — especially in the opening, sizing-up stage of a negotiation — produces more positive responses and higher success ratios on both sides of the table.

How a smile tricks the brain

The ability to decode smiles appears to be hardwired as a survival aid. Because smiling is a submission signal, ancestral humans needed to recognize at a glance whether an approaching stranger was friendly or aggressive — those who could not, perished. The book illustrates this with a photograph of actor Hugh Grant: viewed one way most people read him as relaxed and happy because of his smile, but inverting the image reveals a completely different emotional attitude. Even when the authors cut and pasted Grant's eyes and smile into a horrific-looking face, the brain could still identify the smile when the face was upside down — and could separate the smile from every other facial feature. It is a vivid demonstration of how powerfully a smile registers on us.

Practicing the fake smile — and why liars smile less

The liar's smile

Most people cannot consciously tell a fake smile from a real one, and most are content simply to be smiled at. Because smiling is so disarming, people wrongly assume it is a liar's favorite tool. In fact, Paul Ekman's research showed that when people deliberately lie, most — especially men — smile less than usual, precisely because liars know smiling is associated with lying and so suppress it. When a liar does smile, the smile comes faster than a genuine one and is held much longer, almost like a worn mask.

Left-side asymmetry

A false smile often appears stronger on one side of the face than the other, because both brain hemispheres try to make it look genuine. The cortex region specializing in facial expression sits in the right hemisphere and sends signals mainly to the left side of the body, so false facial emotion is more pronounced on the left side of the face. In a real smile, both hemispheres instruct each side to act with symmetry.

Smugglers smile less

Commissioned by Australian Customs in 1986 to increase contraband seizures, the authors tested the long-standing law-enforcement assumption that liars smile more under pressure. Their analysis of filmed liars showed the opposite: when people lied, they smiled less or not at all, regardless of culture, while innocent, truthful people increased their smiling. Because smiling is rooted in submission, the innocent were unconsciously appeasing their accusers, while professional liars suppressed their smiles and other body signals. It is the same reflex that makes you feel guilty and start smiling when a police car pulls up beside you at the lights even though you have done nothing wrong — which is why fake smiling must always be read in context.

Five common types of smiles

1. The Tight-Lipped Smile

The lips stretch tight into a straight line and the teeth are concealed. It signals that the smiler has a secret, a withheld opinion, or an attitude they will not share. It is a favorite of women who do not want to reveal that they dislike someone, and other women read it clearly as a rejection signal — while most men miss it entirely. The book contrasts businessmen who flash it while withholding the details of their success with Richard Branson, who sports a wide toothy smile and freely explains how he succeeded.

2. The Twisted Smile

This smile shows opposite emotions on each side of the face — one side raised into a grin by the right brain, the other pulled down into an angry frown by the left brain. Mirroring each half separately produces two completely different faces. The Twisted Smile is peculiar to the Western world and can only be done deliberately, so it carries exactly one message: sarcasm.

3. The Drop-Jaw Smile

A practiced smile in which the lower jaw is simply dropped to give the impression of laughing or playfulness. The book lists The Joker in Batman, Bill Clinton, and Hugh Grant as users who deploy it to engender happy reactions in audiences or to win votes.

4. The Sideways-Looking-Up Smile

With the head turned down and away while looking up with a tight-lipped smile, the smiler appears juvenile, playful, and secretive. This coy smile is described as men's favorite everywhere: when a woman does it, it engenders parental, protective male feelings. It was one of Princess Diana's signature smiles — making men want to protect her and women want to be like her — and is a staple of women's courtship repertoire, read by men as a powerful, seductive "come-on" signal.

5. The George W. Bush Grin

A permanent smirk. Ray Birdwhistell found that smiling is most common among middle-class people in the American South — Atlanta, Louisville, Memphis, Nashville, and most of Texas. Bush, a Texan, came from a region that smiles more than the rest of America. The cultural contrast is sharp: in Texas an unsmiling person might be asked if he is "angry about something," while in New York a constant smiler might be asked "What's so funny?"

Why laughter is the best medicine

The physiology

Like smiling, laughter — when it becomes a permanent part of who you are — attracts friends, improves health, and extends life. When we laugh, every organ is affected positively: breathing quickens (exercising the diaphragm, neck, stomach, face, and shoulders), blood oxygen rises (aiding healing and circulation), and the blood vessels near the skin expand, which is why people flush red. Laughter can also lower the heart rate, dilate the arteries, stimulate the appetite, and burn calories. Neurologist Henri Rubenstein found that one minute of solid laughter yields up to forty-five minutes of subsequent relaxation, and Professor William Fry at Stanford reported that one hundred laughs equal roughly a ten-minute rowing-machine workout. Tellingly, an adult laughs an average of fifteen times a day; a preschooler laughs around four hundred.

Smiling moves the brain toward happiness

People who smile or laugh even without feeling especially happy make the "happy zone" in the brain's left hemisphere surge with electrical activity. Richard Davidson, professor of psychology and psychiatry at the University of Wisconsin in Madison, hooked subjects to EEG machines while showing them funny movies and proved that intentionally producing smiles and laughter shifts brain activity toward spontaneous happiness. Arnie Cann at the University of North Carolina found humor counteracts stress: a group who watched comedy videos over three weeks improved more than a control group who watched non-humorous videos, and people with ulcers frown more than those without.

Why we laugh and talk, but chimps don't

Robert Provine, professor of psychology at the University of Maryland, Baltimore, found that human laughter differs physically from our primate cousins'. Chimpanzee laughter sounds like panting — only one sound per inward or outward breath — and it is this one-to-one ratio between breath cycle and vocalization that makes speech impossible for most primates. When humans began walking upright, the upper body was freed from weight-bearing, allowing finer breath control. As a result, humans can chop and modulate an exhalation to produce both language and laughter. Chimps can hold linguistic concepts but cannot physically make the sounds of language.

How humor heals

Laughter stimulates the body's natural painkillers and "feel-good" enhancers — endorphins — which relieve stress and help heal the body. The book's central case is Norman Cousins, diagnosed with the debilitating illness ankylosing spondylitis and told he would live in excruciating pain. Cousins checked into a hotel room, rented every funny movie he could find (the Marx Brothers, Airplane, The Three Stooges), and laughed as hard and loud as he could over and over. After six months of self-administered laughter therapy his illness was, to his doctors' amazement, completely gone — an outcome that produced his book Anatomy of an Illness and launched major research into endorphins. Endorphins are brain chemicals with a composition similar to morphine and heroin; they tranquilize the body while building the immune system, which the author offers as the reason happy people rarely get sick while chronic complainers often seem ill.

Laughing till you cry

Laughter and crying are closely linked physiologically. A hard laugh releases endorphins that produce a tingling "natural high" — the same sensation drug users chase. People who struggle to laugh at life's difficulties often turn to drugs and alcohol to reach the feeling that endorphin-induced laughter produces naturally; alcohol loosens inhibitions and lets people laugh more, which is why well-adjusted people laugh more when drinking while unhappy people grow more despondent or even violent. Paul Ekman found that smiling and laughing faces attract us partly because they affect our autonomic nervous system — we smile when we see a smile and release endorphins — and, conversely, being surrounded by miserable people leads us to mirror their expressions and become morose.

How jokes work

Most jokes work because, at the punch line, something disastrous or painful happens to someone. The unexpected ending "frightens" the brain, and we laugh with sounds similar to a chimp warning others of danger. Even though we consciously know the joke is not real, the laugh releases endorphins as a kind of self-anesthesia. This is why laughter and crying sit so close together: crying is often an extension of a laughing bout, and in a serious emotional crisis — such as hearing of a death — a person who cannot mentally accept the news may begin laughing until reality hits and the laughter turns to tears.

The Laughter Room

In the 1980s, several American hospitals — drawing on Norman Cousins's experience and Dr. Patch Adams's research — created "Laughter Rooms" stocked with joke books, comedy films, and humorous tapes, with regular visits from comedians and clowns. Patients had thirty- to sixty-minute sessions daily. The results were striking: dramatically improved patient health, shorter average hospital stays, fewer painkillers required, and patients who were easier to deal with.

Smiles and laughter are a way of bonding

Robert Provine found that laughter is more than thirty times as likely to occur in a social situation than in a solitary one — it has less to do with jokes than with building relationships. In fact only about 15 percent of laughter follows actual jokes. In his studies, participants watched a humorous clip alone, with a same-sex stranger, and with a same-sex friend; although they rated the clip equally funny in every condition, they laughed significantly less when alone. The frequency and duration of laughter were far greater whenever another person was present — proving that the more social the situation, the more often and the longer people laugh.

Humor sells

Karen Machleit, professor of marketing at the University of Cincinnati, found that adding humor to advertisements increases sales. Humor makes consumers more likely to accept an advertiser's claims and raises source credibility, so a funny ad featuring a famous person becomes even more readily accepted.

The Permanent Down-Mouth

The opposite of the smile is the Down-Mouth expression — both corners of the mouth pulled downward, worn by people who feel unhappy, despondent, depressed, angry, or tense. If a person holds these emotions across a lifetime, the mouth corners can set into a permanent downward position, eventually giving a bulldog-like appearance. Studies show we stand farther from people with this expression, give them less eye contact, and avoid them as they approach. The remedy: practice smiling regularly, which both prevents the permanent set and makes you feel more positive.

Cultural and gender notes

Smiling advice for women

Research by Marvin Hecht and Marianne La France of Boston University found that subordinate people smile more around dominant ones in both friendly and unfriendly situations, while superior people smile around subordinates only in friendly ones. Because women smile far more than men in social and business settings, this can make a woman appear subordinate or weak when facing unsmiling men. The extra smiling is probably inborn rather than learned — by eight weeks of age, baby girls already smile far more than baby boys — fitting women's evolutionary role as pacifiers and nurturers. It does not make a woman less authoritative in fact, but it can make her look less authoritative.

Social psychologist Dr. Nancy Henley of UCLA called a woman's smile "her badge of appeasement," often used to placate a more powerful male. Her research found women smile 87 percent of the time in social encounters versus 67 percent for men, and are 26 percent more likely to return smiles from the opposite sex. In one study, photographs of sad-faced women were rated least attractive by 257 respondents; unsmiling women were read as unhappy, but unsmiling men were read as dominant. The practical lessons: women should smile less — or mirror men's lower smiling — when dealing with dominant men in business, and men who want to persuade women should smile more in all contexts.

Laughter in love

In courtship it is again women who do most of the laughing and smiling, not men, and laughter serves as a gauge of how well a couple is likely to bond. Simply put, the more a man can make a woman laugh, the more attractive she finds him — because the ability to make others laugh reads as a dominant trait, and women prefer dominant males while males prefer subordinate females. Provine also found that a subordinate person laughs to appease a superior, while a superior person makes subordinates laugh without laughing himself to maintain status.

This is why a sense of humor sits near the top of women's priority list in a partner. When a woman says "he's such a funny guy — we spent the whole night laughing," she usually means she laughed and he made her laugh. From a man's perspective, saying a woman has a good sense of humor does not mean she tells jokes — it means she laughs at his. Men instinctively grasp the attraction value of humor and compete with other men to tell the best joke to raise their status (and resent the man who dominates the joke-telling when women are present). The reassuring point: humorous men look more attractive to most women, and humor can be learned.

Summary of the argument

When you smile at someone they almost always return it, producing positive feelings in both parties through simple cause and effect. The evidence is that most encounters run more smoothly, last longer, end better, and improve relationships when smiling and laughing become a habit. Smiles and laughter build the immune system, defend the body against illness, medicate it, sell ideas, teach better, attract friends, and extend life. Humor heals.

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