ISBN: 978-0-393-07335-5

MOLLIE MCNEIL, MY WIFE; AND NATALIE AND SERAFINA KELTNER-

1Jen Science

ANTONY VAN LEEUWENHOEK changed how we look at the natural world. Born in Delft, the Netherlands, in 1632, he came from a family of brewers and basket-makers. Van Leeuwenhoek was peacefully settled into his life as a fabric maker, minor city official, and wine assayer until he started grinding up lenses to build simple microscopes to get a better look at the drapes in his shop. His curiosity led him to place the algae of nearby lakes under his three-to four-inch single-lens microscopes, as well as the cells of fish, his sperm, and the plaque of two old men who had never cleaned their teeth. He was the first to study bacteria, blood cells, and spermatozoa. He opened humanity�s eyes to the microbiological world, changing our understanding of who we are.

This book offers a Darwinian lens onto a new science of positive emotion. We�ll call this new science jen science, in honor of the Confucian concept of jen. Jen is the central idea in the teachings of Confucius, and refers to a complex mixture of kindness, humanity, and respect that transpires between people. Alienated by the violence, the materialism, and the hierarchical religion of his sixth-and fifth-century BC China, Confucius taught a new way of finding the meaningful life through the cultivation of jen. A person of jen, Confucius observes, �wishing to establish his own character, also establishes the character of others.� A person of jen �brings the good things of others to completion and does not bring the bad things of others to completion.� Jen is felt in that deeply satisfying moment when you bring out the goodness in others.

Jen science is based on its own microscopic observations of things not closely examined before. Most centrally, it is founded on the study of emotions such as compassion, gratitude, awe, embarrassment, and amusement, emotions that transpire between people, bringing the good in each other to completion. Jen science has examined new human languages under its microscope�movements of muscles in the face that signal devotion, patterns of touch that signal appreciation, playful tones of the voice that transform conflicts. It brings into focus new substances that we are made of, neurotransmitters as well as regions of our nervous system that promote trust, caring, devotion, forgiveness, and play. It reveals a new way of thinking about the evolution of human goodness, which requires revision of longstanding assumptions that we are solely wired to maximize desire, to compete, and to be vigilant to what is bad.

Seeing the world through this Darwinian lens of jen science could very well shift your jen ratio. The jen ratio is a lens onto the balance of good and bad in your life. In the denominator of the jen ratio place recent actions in which someone has brought the bad in others to completion�the aggressive driver who flips you off as he roars past, the disdainful diner in a pricey restaurant who sneers at less well-heeled passersby. Above this, in the numerator of the ratio, tally up the actions that bring the good in others to completion�a kind hand on your back in a crowded subway car, the young child who compliments the elderly woman on her bathing suit as she nervously dips her toe in a swimming pool, the woman who laughs as a stranger accidentally steps on her foot. As the value of your jen ratio rises, so too does the humanity of your world.

Let�s give the jen ratio a little life. An after-school moment at my daughters� playground yields the following. In the numerator: two boys laugh, giving each other noogies on the head, girls do handstands and cartwheels, giggling at their butt-thumping mistakes, in the soft expanse of a grassy field, kids dog pile on a young boy deliriously clasping the football to his chest. In the denominator: a boy teases a smaller boy about his shoes; two girls whisper about another girl who tries to enter into their game of unicorn. This minute of playground life yields a jen ratio of 3/2, or 1.5. A pretty good scene. In an interminable, eight-minute line to buy stamps I see 24 varieties of exasperation, from sighs to glares to threatening groans, and one guy laughs three times. 3/24 = .125.

One can apply the jen ratio to any realm: our interior life, more satisfying and more trying periods of a marriage, the tenor of a family reunion, the goodwill of a neighborhood, the rhetoric of presidents, the spirit of historical eras. Think of the jen ratio as a lens through which you might take stock of your attempt at living a meaningful life.

2Darwin�s Joys

IN 1967, PAUL EKMAN was lucky to land his Cessna on a small clearing in a jungle of New Guinea (the plane had lost a wheel on takeoff). He arrived with a packet of photos, film equipment, and a hypothesis in hand. He was there thanks to U.S. government malfeasance in South America. A government agency had been funding counterinsurgency research in left-leaning South American countries under the guise of public opinion research. When a congressional committee found out, the funds were quickly shunted to a promising but relatively unknown young researcher�Ekman�for a cross-cultural study of emotion recognition.

Ekman traveled to New Guinea to ascertain whether people from a culture remote from Western influence, a people living in pre-industrial, hunter-gatherer conditions, would interpret photos of facial expressions of six emotions�anger, disgust, fear, happiness, sadness, and surprise�as you or I would. Ekman doubted he would obtain such findings. He was steeped in the cultural relativist assumptions of the era. He had little notion that this work, however it turned out, would catalyze the study of emotion. Nor did he suspect that this work would unravel time-honored notions about the place of emotion in human nature. He was making the trip in the discovery-oriented spirit of Charles Darwin.

3Rational Irrationality

ISTILL REMEMBER THE DAY as clear as a bell. Off to the side of the seventh-grade four square game, the love of my life, Lynn Freitas, approached me with hands coyly behind her back. She came unusually close�we were face to face, separated by nine to ten inches�and with a delighted smile framed by her rolling, curly hair asked, �Hey, Dacher, wanna screw?� A surge of thoughts raced through my mind�at last she had recognized my subtle prepubescent allure, at last my longings would make contact with inexplicable happenings on my middle school playground. As I was in the midst of mumbling an earnest and affirmative reply, she held her hand in front of me, palm up, with a screw lying flat on her tender fingers. All I remember was a roar of laughter from the cabal of finger-pointing girls who had suddenly surrounded me to witness this character assassination.

Had I been a FACS-certified seventh grader and known then what I have learned in studying the nonverbal clues of sexual desire (of which Lynn showed not a scintilla), I probably would have been fooled again; it may be in our best interests to be fooled by those we love. Had I trained my ear to discern the fine acoustics involved in playful teasing, I probably would have detected subtle deviations from truthfulness in the artfully elongated vowels of Lynn�s enunciation (�Hey, Daaacher, wanna screeew�) that would have given away her playful intent. Had I read Nobel Prize-winning economist Thomas Schelling�s The Strategy of Conflict from 1963, I would have understood why I was fooled, or at least known what to look for when Lynn Freitas made her offer.

Schelling observed that most meaningful exchanges�from the promise of undying love or mutual gain in risky business ventures to the strategic threats of diplomats and negotiators�hinge on solving the commitment problem. The commitment problem has two faces. The first is that we must often put aside self-interested courses of action�offers of affairs, chances to gain at colleagues� expense, opportunities to lie to company stockholders�in the service of our long-term commitments to one another. Long-term relations require that we transcend narrow, in-the-moment, pleasure-seeking self-interest.

The second face of the commitment problem may be more challenging: We must reliably identify who is committed to us, we must find those morally inclined individuals to enter into long-term bonds with, we must know who is (and who is not) likely to be faithful and caring, and disinclined to cheat, lie, and sacrifice us in the service of the pursuit of their self-interest. We must quickly make these decisions to avoid being fooled or exploited by the Lynn Freitases of the world on a regular basis. What helps us solve the commitment problem?

Emotion. The very nature of emotional experience�its seeming absoluteness, heat, and urgency�can readily overwhelm narrow calculations of self-interest, allowing us to honor the commitments integral to long-term bonds: monogamy, fairness, duties and obligations. The potent pangs of guilt help us repair our dearest relations, even at great cost to the self. The single-minded feeling of compassion or awe can motivate us to act on behalf of other individuals or collectives, regardless of costs or benefits to the self.

Just as important is the centrality of others� emotional displays in our attempts to discern others� commitments to us. As important as language is, it is striking how impotent it is in conveying the commitments that define the course of life�the sense that someone will really love us through thick and thin, the sense that a colleague will be a lifelong collaborator, the sense that a politician is devoted to the greater good. Words are easy to manipulate. Not so, emotional displays. Emotional displays provide reliable clues to others� commitments because they are involuntary, costly, and hard to fake (as opposed to words, which Lynn Freitas used to dupe me). Emotional displays have much in common with the peacock�s tail or stotting of the red deer: all are metabolically expensive behaviors that are beyond volitional control, and thus less subject to strategic manipulation or deception.

The general claim that Schelling offered: Emotions are involuntary commitment devices that bind us to one another in long-term, mutually beneficial relationships. As Ekman parsed the intricate realm of facial expression, he arrived at a discovery that would provide anatomical support for Schelling�s commitment thesis, and that would lead to a rethinking of the centrality of emotion to our most important bonds. Of the forty-three sets of facial muscles, most are easy to move voluntarily. For example, the pictures that follow represent common facial actions, pregnant with signal value, that most anyone can produce at the drop of a hat, at the behest of a friend, to pass the time in the hotel bathroom, or to win a drunken bet.

A subset of facial muscles, however, are wired differently; they are controlled by different neural pathways originating in the brain. For about 85 to 90 percent of people�actors, sociopaths, politicians, late-night televangelists, and people who take the hundred hours to learn FACS excluded�these muscles are impossible to move voluntarily. If you�re feeling bold, want to put some braggart to the test, or are lacking a bit in levity, try yourself or test whether some other poor soul can produce the following muscle actions:

I�ve asked dozens of children in summer camps, hundreds of undergraduates in lecture courses, dozens of executives in seminars, most of my indulgent friends, and even, I must confess, my two daughters, to try to produce these muscle actions. After many misfires, contorted faces, shakes of disbelief, and the occasional blush, individuals inevitably fail. What these muscles are, Ekman deduced, are the reliable indicators of emotion. These fleeting movements of muscles in the face are the trustworthy signs of specific emotions, such as anger, fear, desire and love, and, by implication, our social commitments.

Consider sympathy, an emotion central to the stability of the social contract, as Adam Smith, David Hume, and Charles Darwin long ago surmised. Social theorists have homed in on sympathy for some time because it backgrounds the individual�s self-interest, and leads to actions that enhance the welfare of others, even at expense to the self. The question is: How do we discern sincere sympathy, or true commitment to others� welfare, from the false promises of demagogues, sociopaths, and hucksters? Robert Frank reasoned, in a synthesis of Schelling�s insights and Ekman�s methodological labors, that the clues to another�s sympathy and commitment to cooperation are found in two simple facial muscle movements (AU1 + AU4, in FACS terminology). Feelings of sympathy, and the commitment to cooperative exchange, are registered in an involuntary facial display that is more trustworthy than its cheap, and readily feigned, copies.

To get a sense of this, compare your reactions to the photos of the two facial displays below. The expression on the left is hard to produce voluntarily. It involves the pulling in and upward of the inner eyebrows, and has been shown in several empirical studies to accompany sympathetic feelings and activation of a region of the nervous system that is associated with caretaking behavior. The facial expression on the right, although quite similar morphologically to the sympathetic display on the left, does not involve activation of these involuntary, reliable facial muscles. It is not a reliable signal of an individual�s interest in your welfare (in fact, the eyebrow raise is a signal with many meanings, including interest, skepticism, weakness, and dramatic emphasis when speaking).

Darwin had claimed that our emotional expressions are distilled tokens of more complex social actions�striking out, soothing, eating, embrace, yelling to escape, vomiting, self-protection. Ekman had taken this analysis one step further, showing that of the thousands of possible configurations of facial muscles, a select few are reliable clues to the individual�s emotions. This subset of facial expressions, by implication, signals an individual�s social commitments, be it likely attack, the inclination to soothe, to be sexually faithful in romantic bonds, or to show concern over social norms and morals.

Emotions feel irrational from the individual�s point of view. Emotions can subvert our best attempts at self-control, composure, autonomy, and a narrow self-interested rationality. I�m not at my best at considering the recommendations of a financial advisor, solving crossword puzzles, or sorting out the costs and benefits of my actions when feeling strong emotion.

Long-term relationships, however, require us to put aside utilitarian, cost-benefit analyses of self-interest. Emotions enable us to enact the costly commitments to another�s welfare, to respect, to maintaining fair and just relations. Emotions are statements to others that we care, and without these statements long-term relations wither and die. Emotions, Martha Nussbaum argues in Upheavals of Thought, are the idiom in which we negotiate our engagements with others. We would live in a lonely, disengaged world were it not for the emotions.

4Survival of the Kindest

IN NOVEMBER 1943, S. L. A. �Slam� Marshall, a U.S. Army lieutenant colonel, arrived with American troops on the beaches of Makin Island to fight the Japanese. After four days of bloody, chaotic combat, the Americans secured the island. In the ensuing calm, Marshall was asked to interview several soldiers to clarify some specifics of the four-day battle, with medals, heroic claims, and rights to wartime stories at stake. Marshall subsequently interviewed hundreds of soldiers who fought in Europe and the Pacific during World War II, often immediately after engagement. In 1947, he published the results from these interviews in Men Against Fire: The Problem of Battle Command.

His interviews yielded an astonishing finding: Only 15 percent of World War II riflemen had fired at the enemy during combat. Often soldiers refused to fire at the enemy with superior officers barking commands nearby and bullets zipping past their heads. In the wake of this revelatory finding, the army radically changed how it prepared soldiers to kill. Infantry training exercises played down the notion that shooting kills humans. Soldiers were taught to shoot at nonhuman targets�trees, hills, bushes, cars, hovels, huts. The effects were dramatic. According to army estimates, 90 percent of soldiers in the Vietnam War fired at their enemies.

If Charles Darwin and his close intellectual peers�Thomas Henry Huxley and Alfred Russel Wallace�were to discuss this finding with Charlie Rose or on C-SPAN�that in the heat of battle soldiers most typically refused to harm fellow human beings in spite of their self-preservation being on the line�they would reach contrasting conclusions. For Alfred Russel Wallace, a codiscoverer of the theory of evolution by natural selection, this concern for the welfare of others would be taken as evidence of how God has shaped human beings� more benevolent tendencies. Wallace argued that while the body was shaped by natural selection, our mental faculties, and most notably our capacity for good, were created by �an unseen universe of the Spirit� (p. 354). It was some kind of spiritual force that kept soldiers from pulling the trigger to end the lives of enemies.

T. H. Huxley, progeny of one of England�s well-known intellectual families, was evolutionary theory�s fiercest early advocate and public spokesman. In Oxford and Cambridge circles he was nicknamed Darwin�s bulldog. He would have readily attributed Marshall�s findings to the constructive forces of culture. In Huxley�s view, human nature is aggressive and competitive, forged by evolution in a violent, selfish struggle for existence. Altruistic actions oriented toward benefiting the welfare of others�soldiers refusing to harm, daily civilities of public life, kindness toward strangers�must be cultivated by education and training. Cultural forces arise to counteract the base instincts that evolution has produced at the core of human nature.

Darwin would have reached yet a different conclusion, parting ways with his two colleagues. Had he been able to do so, he might have placed Marshall�s empirical gem in his first book on humans, Descent of Man, published twelve years after the On the Origin of Species. In Descent, Darwin argued that the social instincts�instincts toward sympathy, play, belonging in groups, caring for offspring, reciprocating acts of generosity, and worrying about the regard of others�are part of human nature. In Darwin�s typically modest but provocative prose:

5Embarrassment

ON JULY 2, 1860, Eadweard Muybridge boarded a stagecoach in San Francisco bound for St. Louis, Missouri, where he was to catch a train and make his way to Europe. There he would search for rare books to fill the shelves in the bookstore that he ran with his brother. In northeastern Texas, things went horribly. The driver of the stagecoach lost control and the coach careened down a hillside. Muybridge was hurled out of the boot of the coach, smashing his face against a tree, damaging a part of his frontal lobes that enables people to draw upon their emotions in making difficult decisions.

After six vague years in England, Muybridge returned to San Francisco. In 1872, he married Flora Shallcross Stone, twenty-one years his junior. While Muybridge was away on assignment for weeks on end, taking photographs of Yosemite and the Indian wars, Flora frequented fashionable theaters and restaurants with the dashing Major Harry Larkyns. Flora soon bore a baby boy. The little boy was more the source of uneasy suspicion than joy for Muybridge. Muybridge�s concerns were quickly confirmed: He found a photo of the baby with �Little Harry� inscribed on the back. When the baby�s nurse confirmed Muybridge�s suspicions�that Harry Larkyns was the father of the baby�Muybridge was overwhelmed.

He took a train to Calistoga, where Larkyns was working at the Yellow Jacket Ranch. Once at the ranch, Muybridge strode up to the front door and summoned Larkyns. When Larkyns arrived, Muybridge stated in matter-of-fact fashion: �Good evening, major, my name is Muybridge,� at which time he raised his Smith & Wesson No. 2 six-shooter and shot Larkyns one inch below his left nipple. Larkyns grabbed his wound, ran through the house to his friends outside, and collapsed and died. A witness to the scene disarmed Muybridge and took him to the parlor, where Muybridge apologized to the women present for the �interruption.�

At Muybridge�s highly publicized trial, which produced an acquittal, several witnesses spoke of the changes the stagecoach accident had produced in his character. After the accident, he seemed like a different man�eccentric, remote, aloof, and cold. His speech and manner of dress were odd. He did not clean himself regularly. He cared little for social outings. He had difficulties keeping track of the contracts that financed his photography. And he demonstrated little or no modesty, no embarrassment at his eccentricities.

What does embarrassment have to do with incivility, remoteness, and murder? To find answers to these questions, I trained my eye in the frame-by-frame view of human social life inspired by Darwin and pioneered by Muybridge himself in his still photography. I slowed down the blur of two-second snippets of embarrassment and studied its fleeting elements�gaze shifts, head movements down, coy, compressed smiles, neck exposures, and glancing touches of the face. At the time I began my research, the display of embarrassment was thought to be a sign of confusion and thwarted intention. My research told a different story, about how these elements of embarrassment are the visible signals of an evolved force that brings people together during conflict and after breeches of the social contract, when relations are adrift, and aggressive inclinations perilously on the rise. This subtle display is a sign of our respect for others, our appreciation of their view of things, and our commitment to the moral and social order. I found that facial displays of embarrassment are evolved signals whose rudiments are observed in other species, and that the study of this seemingly inconsequential emotion offers a porthole onto the ethical brain, which in Muybridge�s case had been destroyed in northeastern Texas over 140 years ago.

6Smile

THE SETI PROJECT is the largest in the world devoted to communicating with intelligent life forms outside of those on Earth. A branch of SETI has brought together anthropologists, mathematicians, physicists, and media and communication experts to solve an intriguing problem: Which symbols should we send out into the infinite expanse of the universe to communicate the altruistic capacities of the human species? Assuming other intelligent life-forms emerged in similar carbon-based chemical processes as we did, how might we, given one shot, communicate our capacity for good to other intelligent minds? The yin-yang symbol? An image of a baby, with round eyes, small mouth, and minuscule mound of a chin? Perhaps, instead, we should rely on sound, given our powerful capacity to communicate vocally. How about the perfect laugh, a soothing sigh, a meditative oohmmmm, or coos between infant and parent?

The question that SETI scholars are debating mirrors one at the heart of this chapter: As our hominid predecessors increasingly lived and worked in close proximity with one another, gathering and distributing plants, fruits, and seeds, sharing the meat of a kill, tending to the needs of vulnerable offspring, moving through gatherings of potential mates and vigilant rivals, what behaviors allowed them to navigate such conflict-rife contexts in cooperative fashion? The classical Greeks had their own answer, one that will anticipate the theme of this chapter�the smile.

As Angus Trumble details in A Brief History of the Smile, in the third to fifth centuries BC, Greek artisans began sculpting the Kouros, a life-sized sculpture that has been found throughout mainland Greece, Asia Minor, and islands in the Aegean Sea. It is a sublimely dynamic sculpture, with upright posture, left foot moving forward, and hands gently clenched in determination. The most captivating aspect of the Kouros, though, is its smile. It is at once modest, poised, expectant, and brimming with contained delight.

In its heyday, the Kouros served as an all-purpose symbol of goodness. It was commonly placed in ceremonial settings as an offering to the gods, to communicate reverence toward the higher powers that controlled the quirks of fate on the earthly ground of Greek life. It was a common presence at funerals, no doubt for those well-off enough to afford such memorializing, serving as an image of the deceased and as a symbol of the gods who would protect the soul of the deceased. For the Greeks, the Kouros represented the soul embodied in the human form.

Evolutionary analysis will tell a similar story about the human smile. In evolution�s toolbox of adaptations that promote cooperation, the smile is perhaps the most potent tool. The smile is visible from hundreds of feet. It triggers, science has discovered, activation in reward centers of the brain. It soothes the stress-related physiology of smiler and perceiver alike. The smile smoothes the rough edges of our social life, creating a medium of benevolent exchange. The right kind of smile brings the good in others to completion. It is one of the first acts of jen in primate evolution.

At stake in our evolutionary analysis of the smile are answers to two questions. The first is straightforward, but has proven to be a surprisingly prickly source of controversy: What does the smile mean? People smile in almost every imaginable context: seeing a loved one, being sentenced to prison, enjoying ice cream and the appalling cooking of a dear friend, hearing that one is pregnant and receiving dire medical news, winning lotteries and losing Olympic competitions. The English language possesses a few words for smiles��smile,� �grin,� �smirk,� �beam��really a paucity of concepts that masks the rich complexity of the realm of smiles. A better understanding of what the smile means will be found by turning to facial anatomy and evolutionary analysis.

A deeper question, however, is at play in our search for the origins of the smile: What are the roots of human happiness? If the right kind of smile is synonymous with happiness, which intuition and dozens of scientific studies suggest is the case, then our search back in time for the social contexts in which the smile emerged is really a search back in time for the origins of human happiness. And this journey would begin with Charles Darwin�s intuitions, and end in studies of smile-like behavior in our more egalitarian primate relatives.

7Laughter

IN THE 1982 FILMQuest for Fire, three hapless Neanderthal males leave their marsh-dwelling tribe in search of fire�the source of their haphazard provision of food and the hierarchical organization of their group. During their quest the three travelers escape from saber-toothed tigers, encounter towering woolly mammoths, and scare off a potential attack from a small tribe of paunchy, red-haired Neanderthals. In this last escapade, they rescue a different kind of early human. She is a more evolved female Homo habilis, finer in bone structure and facial morphology, lacking the carpet of hair covering the body, and adorned in patterned, tribal paints.

This female leads the three males on a primordial Jules and Jim road trip to her village. In this adventure, several distinctions between the Neanderthals and the Homo habilis come into sharp focus. The Homo habilis have developed special tools: a small board with a hole in it and a rounded stick to twist to create fire whenever needed�a radical innovation appreciated even by the dim-witted Neanderthals. They have more complex vocalizations than the grunts, groans, and growls of the Neanderthals. They beautify themselves with rudimentary paints. They live in sophisticated huts, organized in patterns comparable to that of the friendliest cul-de-sacs. They cultivate plants and animals�so critical, Jared Diamond argues, to shifts in the evolution of human culture. They prefer face-to-face sex. And they laugh.

In one scene, the three Neanderthals and their new consort are reclining in the dappled light of a shady tree, grooming, scanning the environment, picking bugs out of the air to eat. Out of the blue a rock bounces off one of the male�s jutting foreheads, prompting a scratch on the head, a cursory look around, and then a return to a quiet state of mindless digestion. The Homo habilis witnesses this simplest form of humor (I spent a good part of my youth bouncing harmless objects�acorns, olives, Good & Plenties�off my brother�s head), and breaks into laughter. The three Neanderthals have no idea what to make of the weird sounds emanating from her mouth.

The thesis that laughter represents a critical evolutionary shift in hominid evolution is not as far-fetched as one might imagine. It is a point that evolutionists Matthew Gervais and David Sloan Wilson have made. The laugh might rightfully lay claim to the status of toolmaking, agriculture, the opposable thumb, self-representation, imitation, the domestication of animals, upright gait, and symbolic language�an evolutionary signature of a great shift in our social organization, accompanied by shifts in our nervous system. What separates mammals from reptiles are the raw materials of laughter�play, and the ability to communicate with the voice (when�s the last time you heard the family gecko howl for a nibble of your salmon or purr for a scratch behind the ears?).

More striking is how human laughter differs from that of our primate relatives�gorillas, chimps, and bonobos. In the most rudimentary sense, the laughter of the great apes resembles our own. Their relaxed open-mouth displays and panting vocalizations look and sound quite familiar. They emit these displays in similar contexts as we do�when being tickled and during rough-and-tumble play. As with humans, chimps and apes are most likely to show open-mouthed play faces in developmental periods (adolescence) and times of day (leading up to feeding) where play can defuse conflict. Yet the laughter of chimps and apes is more tightly linked to inhalation and exhalation patterns than that of humans. As a result, it is emitted as short, repetitive, single-breath pants, and has little acoustic variety.

Human laughter, by contrast, is stunning in its diversity and complexity. It is a language unto its own. There are derisive laughs, flirtatious laughs, singsongy laughs, embarrassed groans, piercing laughs, laughs of tension, silent, head-lightening laughs of euphoria, barrel-chested laughs of strength, laughs that signal the absurdity of the shortness of life and the extent to which we care about our existence, contemptuous laughs that signal privilege and class, and laughs that are little more than grunts or growls. It is because of this heterogeneity that laughter has escaped simple theoretical formulation. It is the analysis of this heterogeneity that will lead to an answer about why we laugh.

8Tease

MALE PEACOCKS are well known for their outlandishly beautiful tails�hypnotically patterned signs of their genetic fitness, alluring to the more dowdy and modest peahen. Less well known is how provocative the florid peacock male can be during the ritualized patterns and exchanges of peacock courtship. Often, when an inquiring peahen approaches, he will turn his back on her, as disinterested as the coldest of cold-shouldering high-school girls. He then stretches out his expansive tail to reveal to her inquisitive eyes his backside. What does the peahen get upon expressing initial interest? Very often, a nose brush with the male peacock�s unseemly behind.

Why such a lack of bird decorum? Is the male peacock relying on the rump presentation as a sexual stimulant, as many primate species do, the most dramatic example being the baboon? Not so, reason Amotz and Avishag Zahavi, in their wonderful The Handicap Principle. These ornithologists suggest that the male peacock is simply testing the peahen. He is teasing and provoking her to gather information about her sexual interest. If the female, facing her consort�s derri�re, circles around to face the male with alacrity and earnest intent, the male knows that she is interested, and not just playing the field or stopping by for a casual exchange of clucks and coos. If she fails to appear, or does so after a few additional milliseconds of dillydallying, he has acquired critical information about her lack of commitment. He can factor this information into his decision about whom to mate with and whom not.

Lest you think that humans have evolved beyond the need to provoke and tease in intimate affairs, consider this exchange between two of literature�s great lovers, Beatrice and Benedick from Shakespeare�s Much Ado About Nothing. This revealing exchange is their first declaration of their affection for one another.

9Touch

FOR THE PAST FIFTEEN YEARS His Holiness the Dalai Lama (HHDL) has been engaging scientists and Tibetan Buddhists in dialogues about the interface between the science of the human nervous system and the 2500-year-old tenets of Tibetan Buddhism. The intention is to uncover commonalities and differences in how these two ways of knowing arrive at claims about the nature of mind, emotion, and happiness.

I have participated in two Buddhism-Science panels, one at MIT and the other through the Dalai Lama Peace Center in Vancouver Canada. Each event evoked out-of-body feelings of the unreality of a wedding day. There was the swirl of the 200 photographers who track HHDL�s every bow, smile, laugh, attentive head nod, finger pointing rhetorical flourish, cough, and sneeze. At MIT, bomb-sniffing dogs circled the space-age auditorium, sniffing under chairs and behind posters protesting for a free Tibetan state. Stone-faced secret service agents, mumbling into collar microphones, stood in dark suits positioned in perfectly proportioned geometric arrangements to protect the space that HHDL moved through. Outside the MIT auditorium at 6 AM hundreds of meditators, peacefully arrayed in rows of upright torsos and braided hair, sat in contemplative anticipation, occasionally awakened by the strike of gongs. The dozens of volunteers who made these events possible, long time practitioners of Tibetan Buddhism from the west, uniformly spoke of being touched by HHDL. Literally touched. One recalled clasping his hands years ago in New York. Another recalled a brush during a bow in Daram Sala India, where HHDL resides. Still another recalled his hand on a shoulder at a reception following a talk. They could remember the precise instant of the touch, the warm feeling that rippled through their bodies, and the lasting change this contact introduced into their lives. Often the act of recalling the touch produced bright eyes, a flush, a head tilt, tearing, and an intimate but remote look in the eyes.

On the stage in Vancouver before our dialogue, HHDL entered stage left and proceeded to greet the four panelists with his customary bow and clasped hands. The sighs, tears, appreciative head nods, goose bumps, and embraces of the 2,500 people in the audience produced a crackling ether that filled the art deco auditorium. I was the last panelist for HHDL to approach. From eighteen inches away I came into contact with HHDL. Partially stooped in a bow, he made eye contact with me and clasped my hands. His eyebrows were raised. His eyes gleamed. His modest smile was poised near a laugh. Emerging out of the bow and clasped hands, he embraced my shoulders and shook them slightly with warm hands.

As he turned to the audience, I had a Darwinian spiritual experience. Goose bumps spread across my back like wind on water, starting at the base of my spine and rolling up to my scalp. A flush of humility moved up my face from my cheeks to my forehead and dissipated near the crown of my head. Tears welled up, along with a smile. I recalled a saying of HHDL�s:

10Love

ON A COLD February weekend, my wife, Mollie, and I and our daughters, then 7 and 5, made the two-hour trip to A�o Nuevo State Park, near Monterey, California. Our aim was to weather the winter storms to view the natural spectacle of migrating elephant seals on their way from Baja to Alaska. We were going in the spirit of Charles Darwin, seeking to study the social patterns of other species to glean insights about our own.

Gale-force winds prevailed. Whipping sheets of sand prickled the young families who gamely trudged on through swirling sand dunes. Failing to appreciate the youthful attention spans of half her audience, our park ranger guide droned on about alpha males, harems, mating rituals, ululations, gestation cycles, and migratory patterns. As we marched on, heads down, eyes shielded by hoodies, children burst into tears, soothing lollipops�last acts of desperate bribery�dropped into the sand.

At last we arrived at a little hill, a purchase, where we were to lie quietly to watch the beached elephant seals gathered below. We lay prostrate on the cool sand in a layer of warm air below the gusts, steadying our binoculars and cameras upon the elephant seals. The enormous 4,500-pound alpha male, heavier than the average SUV, guarded dozens of the females in his harem, each roughly a fourth his size. Occasionally the alpha male would galumph over to a female and flop on top of her. She was lost to view under the rippling gyrations of his fat. At the sight of this burst of passion, other males, poised on the periphery of the harem, would make their move, flopping toward nearby females. Such an intrusion proved more attention-worthy to the alpha male than the paramour below; in the only alacrity he was capable of, he would charge, blubber rolling, toward the intruder. Within ten feet of contact the alpha male would rise up, with weird trunklike snout, and ululate as loud as a corn thrasher. This pattern of rest, attempt at copulation, intrusion, and confrontation went on endlessly. No cuddling, no play, no frolicking, no snout-to-snout nuzzling or mutual gaze in sight.

Our guide rounded us up and led us down a path to the rolling Pacific Ocean to see whether we might spot baby elephant seals, born just a couple of months ago in Baja. Tiny elephant seals at play in the surf would rescue the falling spirits of my daughters. Instead, near the final dune we were to climb, off to the side of our driftwood-marked path, lay a dead baby elephant seal. Our guide explained: �On occasion the male elephant seal, following an ancient evolutionary instinct, will accidentally try to mate with a baby, often to dire ends.� For the rest of the tour, my daughters clung to me, heads buried in my shoulders.

At the end of the tour, after a few polite questions, tips, and halfhearted �thank yous,� we returned to our overstuffed Subaru. Natalie and Serafina sat in their car seats, solemn and quiet. I could feel them trying to map words their parents had used just prior to this misadventure (�family,� �kind of like husbands and wives,� �new babies,� �love�) onto the raw spectacle of elephant seal reproduction. What a flawed endeavor it is to map a concept in the English language (�love,� �family,� �husbands and wives�) onto the immense variety of reproductive arrangements in nature or, for that matter, the complexities and nuances of love.

Had I had the right words and temerity (and had they been several years older), I would have reassured my daughters with new studies from the evolutionary biology of reproduction, so sharply summarized in The Red Queen by Matt Ridley and The Ant and the Peacock by Helena Cronin. Elephant seals are a tournament species, where males devote much of their energy and psyche to violent, winner-take-all competitions for large harems. Humans are more on the pair-bonding end of the continuum, closer to the gibbon, the delicate sea horse, certain voles, and many bird species. In the 8,000 pair-bonding species, like humans, the male is less differentiated than the female in terms of size or florid color, and there is less radical variability in the reproductive outcomes of males (in elephant seals such as those that we observed, almost all offspring are sired by the alpha male). Their future boyfriends, still many years away, would not hoard dozens of girlfriends in the lunchroom and fill entire daycares with their offspring. Instead, they would be theirs and only theirs, at least for awhile.

There is more. In humans, the default is for monogamy, and not the harem tendencies of the elephant seals (no need to unsettle their trust in my marriage with a discussion of the universality of serial monogamy). Sure, one can find elephant seal-like arrangements in human history, in particular in the early emergence of civilizations around the world, when powerful kings started to hoard resources and claim harems in the thousands. The Inca sun king Atahualpa kept 1,500 women in �houses of virgins� located throughout his kingdom, chosen for their pristine beauty most typically before the age of eight. The Indian emperor Udayama kept 16,000 consorts in apartments ringed by fire and guarded by eunuchs. But in early hunter-gatherer culture and in contemporary industrialized cultures, the robust tendency is toward serial monogamy and the intricate challenges of one woman and one man conducting a life together.

Unlike those elephant seals, I would have continued, human males actively contribute to the raising of the offspring. In over 90 percent of mammals, the female is the sole provider of care to offspring; the male doesn�t lift a hand or change a metaphorical diaper. We are different. Human males have the capacity for levels of care for offspring reminiscent of the devotion of the sea horse, the gibbon, and many birds. Tens of thousands of fathers in the United States are primary caretakers, changing diapers, pushing swings, reading Babar and the tongue-twisting wisdom of Dr. Seuss, negotiating sibling conflicts, playing rough-and-tumble, speaking �motherese.�

I would have reminded my daughters that we make friendships. Humans in nonreproductive relations do not flop around like those elephant seals, little cognizant of one another, except in confrontations over mating opportunities. Humans feel deep love for nonkin, in particular for friends. This they would have readily grasped, for they already had folded into devoted friendships. We even feel elevating love for our own kind, humanity, and other species.

Had I had the words or notion, I would have told my daughters that outside of the love they feel for each other (and other kin), there are four great loves in life. There is the love between parent and child, the passion for sexual partners, the enduring devotion for long-term pair-bonders, and the softer but rock-solid love for nonkin, most typically friends and fellow humans.

11Compassion

ONE DAY WHILE FIGHTING in the Spanish civil war, George Orwell encountered an enemy Fascist face-to-face. The soldier came running by, panting, half dressed, stumbling, holding up his pants with clenched hand. Orwell refused to shoot. Later he reflected: �I did not shoot partly because of that detail about the trousers. I had come here to shoot at �fascists� but a man who is holding up his trousers isn�t a �Fascist,� he is visibly a fellow-creature, similar to yourself, and you don�t feel like shooting at him.� The sight of the Fascist�s bare chest, his skin, his disheveled condition, had short-circuited Orwell�s instinct to kill.

In Humanity, historian Jonathan Glover documents many such �sympathy breakthroughs� in the wars of the twentieth century�in Stalin�s purges, the My Lai massacre, the killing fields in Cambodia, the genocide in Rwanda. These are moments when soldiers break free from the dutiful honoring of the military code, from strict orders to shoot on sight, and are overwhelmed by the humanity of the humans they are killing. Most often it is when encountering children and women�for example, the toddlers and pregnant women beheaded and disemboweled in the My Lai massacre. Most often the sympathy breakthroughs are triggered by eye-to-eye contact, the sight of the enemy�s pupils, the pores on his skin, oblique movements in his eyebrows.

No sympathy breakthrough was more dramatic than that of Mikl�s Nyiszli, a medical doctor at a Nazi concentration camp. One day as a gas chamber was being cleared of bodies, a young girl of sixteen was found alive at the bottom of the rigor mortis pile of thin-limbed, stiffening corpses. The attending staff reflexively offered the young girl an old coat, warm broth, tea, and reassuring touch to her shoulders and back. Nyiszli tried to persuade the concentration camp�s commandant to save her. One proposal was to hide her amid German women working at the camp. The commandant toyed with this possibility momentarily but in the end had her killed by his method of choice�the young girl was shot in the back of the neck.

Human history, Glover contends, can be thought of as a contest between cruelty and compassion, tellingly revealed in wartime sympathy breakthroughs, when the force of compassion overwhelms the edicts of war. You could make the same case about human nature. Fight/flight tendencies of self-preservation are continually at odds with tendencies to care in the electrochemical flow of our nervous systems. The content of the mind shifts between the press of self-interest and the push of compassion. The ebb and flow of marriages, families, friends, and workplaces track the dynamic tension between these two great forces�raw self-interest and a devotion to the welfare of the other. The study of emotion is experiencing its own �sympathy breakthrough� thanks to recent studies of compassion, which are revealing this caretaking emotion to be built into our nervous systems. The study of this emotion holds new clues about the health of marriages, families, and communities.

12Awe

ONE AFTERNOON in a botany class at the University of Wisconsin, Madison, John Muir heard a fellow student explain how the flower of an enormous black locust tree is a member of the pea family. That the giant black locust tree and the frail pea plant, so remote in size, form, and apparent design, shared an evolutionary history astounded Muir. He later wrote: �This fine lesson charmed me and sent me flying to the woods and meadows in wild enthusiasm.�

Shortly thereafter, Muir left college. He walked 1,000 miles on a naturalist�s pilgrimage to Florida. He then moved west, to California, and in the summer of 1869, at the age of twenty, herded a couple hundred sheep through the Sierra Nevada Mountains on a trail that wound its way to Yosemite. During this trip he kept a small diary attached to his leather belt. He wrote almost daily entries about these first experiences, which eventually were published as My First Summer in the Sierras. A few days into this trip, Muir writes:

SURVIVAL OF THE KINDEST

In November 1943, S. L. A. �Slam� Marshall, a U.S. Army lieutenant colonel: S. L. A. Marshall, Men Against Fire: The Problem of Battle Command (Norman, OK: University of Oklahoma Press, 1947/2000).

they would reach contrasting conclusions: For an excellent summary of early evolutionary views of altruism, see Helena Cronin, The Ant and the Peacock. (New York: Cambridge University Press, 1991), chap. 15.

In Descent, Darwin argued that the social instincts: The Descent of Man, and Selection in Relation to Sex (London: John Murray, 1871), chap. 4.

�The following proposition�: Ibid., 84.

�Such actions as the above�: Ibid., 95.

at the top of my list would be the field notes of a Cro-Magnon anthropologist: Several books portray the social lives of our hominid predecessors: David Christian, Maps of Time: An Introduction to Big History (Berkeley, CA: University of California Press, 2004). 139�332; Stephen Mithen, After the Ice: A Global History of Human History 20,000 to 5000 BC (Cambridge, MA: Harvard University Press, 2006); Nicholas Wade Before the Dawn: Recovering the Lost History of Our Ancestors (New York: Penguin Press, 2007), 51�180.

A detailed portrayal of the day in the life of our hominid predecessors would shed light on our environment of evolutionary adaptedness (EEA): John Tooby and Leda Cosmides, �The Psychological Foundations of Culture,� in The Adapted Mind: Evolutionary Psychology and the Generation of Culture, ed. Jerome H. Barkow, Leda Cosmides, and John Tooby (New York: Oxford University Press, 1992), 163�228.

We can turn to studies of our closest primate relatives, chimpanzees and bonobos in particular: Several books capture the social dimensions of mammalian evolution that lay the foundation for the analysis of emotions that I offer: Frans B. M. de Waal, Good Natured: The Origins of Right and Wrong in Humans and Other Animals (Cambridge, MA: Harvard University Press, 1996); John R. Krebs and Nicholas B. Davies, An Introduction to Behavioral Ecology (Oxford: Blackwell Press, 1993); Jared Diamond, The Third Chimpanzee (New York: Harper Perennial, 1992); Frans B. M. de Waal, ed., Tree of Origin: What Primate Behavior Can Tell Us About Human Social Evolution (Cambridge, MA: Harvard University Press, 2001), 121�43; Marc Hauser, The Evolution of Communication, (Cambridge, MA: MIT Press, 1996).

first attempts at visual art and music: Stephen Mithen, The Prehistory of the Mind: The Cognitive Origins of Art and Science (London: Thames and Hudson, 1996); D. Christian, Maps of Time: An Introduction to Big History (Berkeley, CA: University of California Press, 2004).

detailed observations of contemporary hunter-gatherer societies: Paul R. Ehrlich, Human Natures. Genes, Cultures, and the Human Prospect (New York: Penguin, 2002); Melvin Konner, The Tangled Wing: Biological Constraints on the Human Spirit (New York: Holt, 2003); Iren�us Eibl-Eibesfeldt, Human Ethology (New York: Aldine de Gruyter, 1989).

the prevalence of caregiving, a hallmark feature of higher primates: Sarah Blaffer Hrdy has written brilliantly about the prevalence of caretaking behavior in different primates and how it is an often overlooked basis of alliances and strategic exchanges. Hrdy, Mother Nature (New York: Ballantine, 1999). For a rigorous discussion of human caregiving, read Shelley E. Taylor, The Tending Instinct (New York: Henry Holt, 2002).

as Frans de Waal has observed: de Waal, Good Natured: The Origins of Right and Wrong in Humans and Other Animals (Cambridge, MA: Harvard University Press, 1996), chap. 2.

Our hominid predecessors evolved bigger brains: Ehrlich, Human Natures, chap. 6.

�carried in a sling�: Konner, The Tangled Wing, 306.

Cooperative child rearing, where relatives and friends traded off duties: Hrdy, Mother Nature, 90�95.

consistent evidence of cooperative hunting for meat: Stephen Mithen, Singing Neanderthals: The Origins of Music, Language, Mind, and Body (Cambridge, MA: Harvard University Press, 2007), 238.

fall to their deaths: ibid., 238.

morphological changes that gave rise to our remarkable capacity to communicate: Marc D. Hauser, The Evolution of Communication (Cambridge, MA: MIT Press, 1996).

Unlike our primate relatives, the human face has relatively little obscuring hair: Nina Jablonski, Skin: A Natural History (Berkeley, CA: University of California Press, 2006), 43.

allowing for a much richer vocabulary of expressive behavior originating in the face: D. Matsumoto et al., �Facial Expressions of Emotion,� in Handbook of Emotion.

The evolving capacity to communicate is even more pronounced in the human voice: Ehrlich, Human Natures, 152.

to represent and spread information across time and space with language: Robert Boyd and Peter J. Richardson, eds., Culture and the Evolutionary Process (Chicago: University of Chicago Press, 1985), 204�40.

our basic emotional tendencies can quickly spread to others, through mimicry, imitation, and communication: For a superb review of the evolution of the capacity to imitate and empathize, see S. D. Preston and F.B. M. de Waal, �Empathy: Its Ultimate and Proximate Bases,� Behavioral and Brain Sciences 25 (2002): 1�72.

In research with my colleague Cameron Anderson: C. Anderson, O.P. John, D. Keltner, and A. Kring, �Social Status in Naturalistic Face-to-Face Groups: Effects of Personality and Physical Attractiveness in Men and Women,� Journal of Personality and Social Psychology 81 (2001): 118�29.

Female adults attain comparable levels of status with just as much alacrity and effect: Ibid. We found few differences in how women and men ascribe status to other women and men in their groups. High-status women and men show similar tendencies to keep their elevated positions of power over time. The one difference we did document is that group members achieved consensus, or agreement, in their judgments of the status of men a bit faster than in their judgments of women. It is also important to bear in mind that these are status judgments in informal groups. It is very likely that within institutions with historical sex-based differences in status (for example, the U.S. Senate), one is likely to find differences in judgment.

Yet the hierarchical social organization of higher primates and early humans differs dramatically from that of other species: One of the first scientists to make this point was Christopher Boehm. Boehm, Hierarchy in the Forest: The Evolution of Egalitarian Behavior (Cambridge, MA: Harvard University Press, 1999). See also Dacher Keltner, �The Power Paradox,� Greater Good 8 (2008): 14�17.

Frans de Waal has found: Chimpanzee Politics (New York: Harper and Row, 1982) and Peacemaking Among Primates (Cambridge, MA: Harvard University Press, 1989).

Instead, it is the socially intelligent individuals who advance the interests of other group members (in the service of their own self-interest) who rise in social hierarchies: Several new lines of research lend support to this counterintuitive claim. In a recent review, we summarize how socially energetic, outgoing individuals gain power in social groups, and how aggressive, manipulative, Machiavellian types often lose power. Andersen et al., �Social Status in Naturalistic Face-to-Face Groups: Effects of Personality and Physical Attractiveness in Men and Women,� Journal of Personality and Social Psychology 81 (2001): 1108�29. Stephane Cot� has recently documented that socially intelligent individuals�that is, those individuals who are able to understand their own emotions and those of other group members�acquire leadership in organizations. S. Cot� and C. T. H. Miners, �Emotional Intelligence, Cognitive Intelligence, and Job Performance,� Administrative Science Quarterly 51 (2006): 1�28. Perhaps the most dramatic example of this thesis is recent work by Cameron Anderson and colleagues, who have found that individuals in social groups who have modest assessments of their own power actually keep positions of power, whereas individuals who have inflated assessments of power lose power over time. C. Anderson et al., �Knowing your Place: Self-Perceptions of Status in Face-to-Face Groups,� Journal of Personality and Social Psychology 91, no. 6 (2006): 1094�1110. We have long been guided by Machiavellian analyses of power, which suggest that effective leadership requires deception, strategic manipulation, pitting group members against one another, and being feared. The new empirical science of power is proving this to be an erroneous set of assumptions. See Keltner, �The Power Paradox.�

who can tell a good joke or tease in ways: In our research on teasing we have found that individuals who are highly esteemed by other group members are quite adept at teasing in ways that are playful, D. Keltner et al., �Teasing in Hierarchical and Intimate Relations,� Journal of Personality and Social Psychology 75, no. 5 (1998): 1231�47.

bullies, who resort to aggression, throwing their weight around, and raw forms of intimidation and dominance, in point of fact, are outcasts and low in the social hierarchy: D. Olweus, �Stability of Aggressive Reaction Patterns in Males: A Review,� Psychological Bulletin 86 (1979): 852�75.

adorn and beautify themselves in an arms race of beauty to attract resource-rich mates: Darwin, Descent, chaps. 19�20. For an erudite and illuminating extension of Darwin�s ideas, see Geoffrey Miller, The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature (New York: Anchor, 2000). For a playful treatment of the evolutionary biology of sex, see O. Judson, Dr. Tatiana�s Sex Advice to All Creation (New York: Owl, 2002).

This logic of competing interests extends to parent-offspring relations: Hrdy, Mother Nature, chap. 18.

This parent-offspring conflict even extends to mother-fetus relations: D. Haig, �Evolutionary Conflicts in Pregnancy and Calcium Metabolism�A Review,� Placenta 25. Supplement A. Trophoblast Research 18 (2004): S10�S15.

In an observational study of American families: Judy Dunn and her colleagues have done revealing research on the dynamics of family conflict, and how those conflicts lay a foundation for talks about emotion and morality, and the development of empathy and conflict resolution strategies. J. Dunn and C. Herrera, �Conflict Resolution with Friends, Siblings and Mothers: A Developmental Perspective,� Aggressive Behavior 23 (1997): 343�57; Dunn and P. Munn, �Becoming a Family Member: Family Conflict and the Development of Social Understanding in the Second Year,� Child Development 56 (1985): 480�92.

This kind of sibling conflict: Frank J. Sulloway, Born to Rebel: Birth Order, Family Dynamics, and Creative Lives (New York: Pantheon, 1996).

who documented how our primate relatives reconcile after aggressive encounters: Jane Goodall, The Chimpanzees of Gombe: Patterns of Behavior (Cambridge, MA: Harvard University Press, 1986). Frans B. M. de Waal, �The Integration of Dominance and Social Bonding in Primates,� Quarterly Review of Biology 61 (1986): 459�79; de Waal and A. van Roosmalen, �Reconciliation and Consolation among Chimpanzees,� Behavioral Ecology and Sociobiology 5 (1979): 55�66.

the prevailing wisdom: Konrad Lorenz, On Aggression, trans. M. Latzke, (London: Methuen, 1967).

Recent studies have found that wolves: For an excellent review of the literature on ostracism, see K. Williams, �Ostracism,� Annual Review of Psychology 58 (2007): 425�52.

our survival depends on healthy, stable bonds with others: R. F. Baumeister and M. R. Leary, �The Need to Belong: Desire for Interpersonal Attachments as a Fundamental Human Motivation,� Psychological Bulletin 117 (1995): 497�529.

We are relative prudes compared to these primate relatives: Matt Ridley, The Red Queen (New York: HarperCollins, 1993), 213�17.

Bonobo females are sexually active for about five years: Frans B. M. de Waal, �Bonobo Sex and Society,� Scientific American 272 (March 1995): 82�88.

This sexual organization had several important implications: Jared Diamond, Why Is Sex Fun? The Evolution of Human Sexuality (New York: Basic Books, 1997).

sexual monogamy was the most common sexual pattern: Helen Fisher, Anatomy of Love (New York: Simon & Schuster, 1993).

In The Evolution of Cooperation: Robert Axelrod, The Evolution of Cooperation, (New York: Basic Books, 1984).

Built into the human organism, therefore, must be a set of mechanisms that reverse the cost-benefit analysis of giving: Sober and Wilson, Unto Others, chap. 1.

Jonathan Haidt has called this state elevation: J. Haidt and D. Keltner, �Appreciation of Beauty and Excellent (Awe, Wonder, Elevation),� in Character Strengths and Virtues, ed. Christopher Peterson and Martin E.P. Seligman (New York: Oxford University Press, 2004), 537�51.

T. C. Boyle, excerpts from Drop City. Copyright � 2003 by T. Coraghessan Boyle. Used by permission of Viking Penguin, a division of Penguin Group (USA) Inc. and Georges Borchardt, Inc., for the author.