These are elephant-sized motives large enough to leave footprints in national economic data.

Then he read Hierarchy in the Forest by anthropologist Christopher Boehm, a book that analyzes human societies with the same concepts used to analyze chimpanzee communities.

The point is, people don’t typically think or talk in terms of maximizing social status—or, in the case of medicine, showing conspicuous care. And yet we all instinctively act this way. In fact, we’re able to act quite skillfully and strategically, pursuing our self-interest without explicitly acknowledging it, even to ourselves.

Self-deception is therefore strategic, a ploy our brains use to look good while behaving badly.

When consumers are asked why they bought an expensive watch or high-end handbag, they often cite material factors like comfort, aesthetics, and functionality. But Veblen argued that, in fact, the demand for luxury goods is driven largely by a social motive: flaunting one’s wealth.

We now realize that our brains aren’t just hapless and quirky—they’re devious.

Emily Pronin calls it the introspection illusion, the fact that we don’t know our own minds nearly as well as we pretend to.

This book attempts to shine light on just those dark, unexamined facets of public life: venerated social institutions in which almost all participants are strategically self-deceived, markets in which both buyers and sellers pretend to transact one thing while covertly transacting another.

our institutions harbor giant, silent furnaces of intra-group competitive signaling, where trillions of dollars of wealth, resources, and human effort are being shoveled in and burned to ash every year, largely for the purpose of showing off.

Why can’t we be honest with ourselves? The answer is that our thoughts aren’t as private as we imagine. In many ways, conscious thought is a rehearsal of what we’re ready to say to others. As Trivers puts it, “We deceive ourselves the better to deceive others.”

Individual primates can (and do) groom themselves, but they can only effectively groom about half their bodies. They can’t easily groom their own backs, faces, and heads. So to keep their entire bodies clean, they need a little help from their friends.1 This is called social grooming

•Most primates spend far more time grooming each other than necessary for keeping their fur clean.

•Even more puzzling is the fact that primates spend a lot more time grooming each other than they spend grooming themselves.

By grooming each other, primates help forge alliances that help them in other situations.

The political function of grooming also explains why grooming time across species is correlated with the size of the social group, but not the amount of fur.

altruistic babblers develop a kind of “credit” among their groupmates—what Zahavi calls prestige status.

self-deception can be useful when facing an adversary with mind-reading powers.

as tall as arboreally possible.

This is what’s known in the literature as the social brain hypothesis, or sometimes the Machiavellian intelligence hypothesis.3 It’s the idea that our ancestors got smart primarily in order to compete against each other in a variety of social and political scenarios.

social status among humans actually comes in two flavors: dominance and prestige.

Prestige, meanwhile, seems much less competitive, at least on the surface.15 It’s all about respect, which can’t be taken by force, but rather must be freely conferred by admirers. Nevertheless, there’s only so much respect to go around.

With the appropriate translations, chimps’ political behaviors are intelligible to us; we recognize in them the same goals and motivations that we exhibit when we politick with our fellow humans.

Two-against-one maneuvering is what lends chimpanzee power struggles both their richness and their danger. Coalitions are key. No male can rule by himself, at least not for long.

Castiglione wrote The Book of the Courtier for those of lesser nobility who sought favor at court.

A signal, in evolutionary biology,25 is anything used to communicate or convey information.

Signals are said to be honest when they reliably correspond to an underlying trait or fact about the sender. Otherwise they are dishonest or deceptive.

Sometimes it’s even necessary to do something risky or wasteful in order to prove that you have a desirable trait. This is known as the handicap principle.

Thus signals are often arranged into a hierarchy, from non-signals to signals to counter-signals. Outsiders to an interaction may not always be able to distinguish non-signals from counter-signals. But insiders usually know how to interpret them, if only on an intuitive level.

But humans are different. Unlike the rest of nature, we can sometimes see ahead and coordinate to avoid unnecessary competition. This is one of our species’ superpowers—that we’re occasionally able to turn wasteful competition into productive cooperation.

These instincts run deep.

But before and beneath the communication challenge lies a more fundamental challenge: how to ensure that everyone, even the most powerful members of the community, abide by its norms.

When we do something “wrong,” we have to worry about reprisal not just from the wronged party but also from third parties.

Collective enforcement, then, is the essence of norms. This is what enables the egalitarian political order so characteristic of the forager lifestyle.

Paul Bingham calls this “coalition enforcement,” highlighting the fact that norm violators are punished by a coalition, that is, people acting in concert.

With weapons, however, landing the first blow can yield a decisive advantage. A weaker human can maim or kill a stronger one with just a single large rock to the head or sharp rock to the neck.

Another way weapons alter the balance of power applies to projectile weapons like stones or spears. Such distance weapons make it much easier for a coalition to gang up on a single individual.

That’s why humans have at least two other tricks up our sleeves to incentivize good norm-following behavior: gossip and reputation.

Someone who helps evict a cheater will be celebrated for her leadership. Who would you rather team up with: someone who stands by while rules are flouted, or someone who stands up for what’s right?

What Axelrod found is that, in most situations (involving a variety of different costs and benefits, including the costs of helping to punish), people have no incentive to punish cheaters. However—and this was Axelrod’s great contribution—the model can be made to work in favor of the good guys with one simple addition: a norm of punishing anyone who doesn’t punish others. Axelrod called this the “meta-norm.”

By targeting intentions rather than actions, norms can more precisely regulate the behavior patterns that cause problems within communities.

Consider how awkward it is to answer certain questions by appealing to selfish motives. Why did you break up with your girlfriend? “I’m hoping to find someone better.” Why do you want to be a doctor? “It’s a prestigious job with great pay.” Why do you draw cartoons for the school paper? “I want people to like me.”

The most basic way to get away with something—whether you’re stealing, cheating on your spouse, or just picking your nose—is simply to avoid being seen.

Eyes that are looking straight at us jump out from a crowd.

Shame is the anguish we feel at being seen by others in degrading circumstances.

We typically treat discretion or secret-keeping as an activity that has only one important dimension: how widely a piece of information is known. But actually there are two dimensions to keeping a secret: how widely it’s known and how openly12 or commonly it’s known.

Pretexts are a broad and useful tool for getting away with norm violations. They make prosecution more difficult by having a ready explanation for your innocence. This makes it harder for others to accuse and prosecute you. And as we’ve seen, a pretext doesn’t need to fool everyone—it simply needs to be plausible enough to make people worry that other people might believe it.

Neither party needs to be consciously aware that they’re performing in front of this imagined cast; this is simply how people, with years of practice, learn to act in order to save face.

We show off our bodies by wearing flattering clothes.

mixed-motive games. These are scenarios involving two or more players whose interests overlap but also partially diverge. Thanks to the overlap, the players have an incentive to cooperate, but thanks to the divergence, they’re also somewhat at odds with each other.

mixed-motive games contain the kind of incentives that reward self-deception.

The entire value of strategic ignorance and related phenomena lies in the way others act when they believe that you’re ignorant. As Kurzban says, “Ignorance is at its most useful when it is most public.”20 It needs to be advertised and made conspicuous.

Sabotaging yourself works only when you’re playing against an opponent with a theory-of-mind.

Wear a mask long enough and it becomes your face.

In fact, we often measure loyalty in our relationships by the degree to which a belief is irrational or unwarranted by the evidence. For example, we don’t consider it “loyal” for an employee to stay at a company when it’s paying her twice the salary she could make elsewhere; that’s just calculated self-interest. Likewise, it’s not “loyal” for a man to stay with his girlfriend if he has no other prospects. These attachments take on the color of loyalty only when someone remains committed despite a strong temptation to defect.

What this means for self-deception is that it’s possible for our brains to maintain a relatively accurate set of beliefs in systems tasked with evaluating potential actions, while keeping those accurate beliefs hidden from the systems (like consciousness) involved in managing social impressions.

But the conclusion from the past 40 years of social psychology is that the self acts less like an autocrat and more like a press secretary. In many ways, its job—our job—isn’t to make decisions, but simply to defend them. “You are not the king of your brain,” says Steven Kaas. “You are the creepy guy standing next to the king going, ‘A most judicious choice, sire.’

Wilson writes about the “adaptive unconscious,” the parts of the mind which lie outside the scope of conscious awareness, but which nevertheless give rise to many of our judgments, emotions, thoughts, and even behaviors.

But they aren’t fooling anyone; no one with a healthy bladder needs to pee that frequently. Instead these toddlers simply don’t want to go to sleep—that’s their true motive—and they’re using “potty” as a bedtime stalling tactic. It’s an excuse, a pretext, a counterfeit reason.

These two examples illustrate one of the most effective ways to rationalize, which is telling half-truths. In other words, we cherry-pick our most acceptable, prosocial reasons while concealing the uglier ones.

•Parents will often enforce kids’ bedtimes “for their own good,” when a self-serving motive seems just as likely—that parents simply want an hour or two of peace and quiet without the kids.

•Minor impediments are often exaggerated to avoid unwanted social encounters: “I’m not feeling well today” as an excuse not to go work, for example, or “I’m too busy” to decline a meeting.

the fact that we’re largely unconscious of the messages we’re sending with our bodies.

When body language becomes a deliberate performance, it seems forced, perhaps even creepy.

“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.”

A cue is similar to a signal, in that it conveys information, except that it benefits only the receiver.

Body language, however, is mostly not arbitrary.14 Instead, nonverbal behaviors are meaningfully, functionally related to the messages they’re conveying.

And owing to these consequences, body language is inherently more honest than verbal language. It’s easy to talk the talk, but harder to walk the walk.

So in matters of life, death, and finding mates, we’re often wise to shut up and let our bodies do the talking.

(Note that eye behaviors are especially hard for third parties to notice, making them ideal for use as discreet signals.)

More generally, any act of following or copying another person’s behavior—from mimicry on the dance floor to the call-and-response routines common in religious ceremonies—demonstrates a leader’s ability to inspire others to follow.

Shaking hands is symmetric and fundamentally egalitarian; it’s a ritual between supposed equals. Hand-kissing, however, is inherently asymmetric, setting the kisser apart from, and subordinate to, the recipient of the kiss. The kisser must press his lips on another person’s (potentially germ-ridden) hands, while simultaneously lowering his head and possibly kneeling. This gesture is submissive, and when it’s performed freely, it’s an implicit pledge of loyalty.

Of all the signals sent and received by our bodies, the ones we seem least aware of are those related to social status. And yet, we’re all downright obsessed with our status, taking great pains to earn it, gauge it, guard it, and flaunt it. This is a source of great dramatic irony in human life.

When you’re feeling meek, you generally want to be a wallflower. But when you’re feeling confident, you want the whole world to notice. In the animal kingdom, this “Look at me!” strategy is known as aposematism.

But status is more than just an individual attribute or attitude—it’s fundamentally an act of coordination. When two people differ in status, both have to modify their behavior.

In the presence of a dominant person, our behavior is governed by avoidance instincts: fear, submission, and appeasement.

Our behavior around prestigious people is governed by approach instincts.

In fact, one of the best predictors of dominance is the ratio of “eye contact while speaking” to “eye contact while listening.” Psychologists call this the visual dominance ratio.

The less his Press Secretary knows about these motives, the easier it is to deny them with conviction.

This is the magic of nonverbal communication. It allows us to pursue illicit agendas, even ones that require coordinating with other people, while minimizing the risk of being attacked, accused, gossiped about, and censured for norm violations.

Laughter1—chuckles, chortles, giggles, and guffaws—

It’s a response to social cues, laced with interpersonal significance, and yet “we”—the conscious, deliberate, willful parts of our minds—don’t get to decide when we do it.5

Consider how we often use humor as an excuse to trot out our most taboo subjects: race, sex, politics, and religion.

We can say things in the comedic register that we’d never dream of saying in a straight-faced discussion.

This empirical, biological study of laughter produced a few key observations. The most important observation is that we laugh far more often in social settings than when we’re alone—30 times more often, in Provine’s estimate.

When Provine studied 1,200 episodes of laughter overheard in public settings, his biggest surprise was finding that speakers laugh more than listeners—about 50 percent more, in fact.

Play, according to zoologists, is a mode of behavior in which animals, especially young ones, explore the world and practice skills that will be important later in life. It’s a voluntary, nonfunctional (i.e., impractical22) activity undertaken in a safe, relaxed setting.

And what Bateson realized was that, in order to play fight, the monkeys needed some way to communicate their playful intentions—some way to convey the message, “We’re just playing.” Without one or more of these “play signals,” one monkey might misconstrue the other’s intentions, and their playful sparring could easily escalate into a real fight.24

Here, for example, is a joke that flirts with, but doesn’t actually consummate, a norm violation:

A real danger of laughter, then, is the fact that we don’t all share the same norms to the same degree. What’s sacred to one person can be an object of mere play to another.

When the popular girls laugh at Maggie, then, their brains are running the same algorithm that ours are running when we laugh at prison rape or the Darwin Awards.48

Laughter, then, shows us the boundaries that language is too shy to make explicit. In this way, humor can be extremely useful for exploring the boundaries of the social world.

We’re so eager to speak, in fact, that we have to curb our impulses via the norms of conversational etiquette.

Now, suppose you meet up with an old acquaintance from school—let’s call him Henry—and the two of you start sharing tools with each other. Broadly speaking, you have two stances you can take toward Henry. You can treat him either as a trading partner or as a potential ally (whether as a mate or otherwise). If you’re looking to trade, you care mostly about the tools he can give you in any one exchange—specifically, the tools you don’t already own. But if you’re looking for an ally, you care less about the specific tools you receive from him, and much more about the full extent of his toolset—because when you team up with Henry, you effectively get access to all his tools. The ones he gives you during any individual exchange may be useful, but you’re really eyeing his backpack. And while you can’t look directly inside it, you can start to gauge its contents by the variety of tools he’s able to pull from it on demand. The more tools he’s able to produce, the more he probably has tucked away in the backpack. And again, you’re looking for a backpack full of tools that are both new to you and useful to the things you care about. If Henry can consistently delight you with new, useful artifacts, it speaks to the quality of his backpack and therefore his value as an ally.

“verbal plumage.”