The Elephant in the Brain_Hidden Motives in Everyday Life

by Robin Hanson

  But we see this choice—of whether to look inward and confront the elephant or continue to avert our gaze—as similar to the choice Morpheus offers Neo in The Matrix. “After this,” Morpheus warns, holding out a blue pill in one hand and a red pill in the other, “there is no turning back. You take the blue pill—the story ends, you wake up in your bed and believe whatever you want to believe. You take the red pill—you stay in Wonderland, and I show you how deep the rabbit hole goes.”9

  If curiosity killed the cat, then Kevin and Robin would be dead cats. We just can’t resist an offer like this. We choose the red pill, and hope that you, dear reader, feel likewise.

  PART I

  Why We Hide Our Motives

  1

  Animal Behavior

  Before we get mired in the complexities of human social life, let’s start at a simpler beginning. Because humans are an animal species, we can learn a lot about ourselves by studying other animals (and even plants, as we’ll see in the next chapter). In fact, it can be especially useful to study other species because we have fewer preconceptions about them. Think of it as a “training wheels” exercise, if you will.

  In this chapter, we’re going to take a quick look at two animal behaviors that are hard to decipher. In each case, the animals appear to be doing something simple and straightforward, but as we dig below the surface—the same way we’ll approach our own behavior in later chapters—we’ll find extra layers of complexity.

  Note, however, that these nonhuman animals don’t necessarily hide their motives like we do, psychologically; if their motives seem cryptic, it’s not because they’re playing mind games. We’ll discuss this in more detail at the end of the chapter.

  SOCIAL GROOMING

  Let’s start with grooming behavior among primates. While humans are relatively hairless, most other primates have thick fur all over their bodies. When left unchecked, this fur quickly becomes matted with dirt and debris. It also makes an attractive home for fleas, lice, ticks, and other parasites. As a result, primate fur needs periodic grooming to stay clean.

  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.2

  Picture two male chimpanzees engaged in an act of social grooming. One chimp—the groomee—sits hunched over, exposing his full backside. The other chimp—the groomer—crawls up and begins examining the first chimp’s fur. He’ll typically spend a few minutes scratching and picking at it with his fingers, using his opposable thumbs to pull out bits of stray matter. It’s a purposeful activity that requires a good deal of attention and focus.

  If we could somehow ask the grooming chimp what he’s doing, he might give a pragmatic explanation: “I’m trying to remove these bits and pieces from my friend’s back.” That’s the purpose of the activity and what his attention is focused on. He might also cite the logic of straightforward reciprocity: “If I groom my friend’s back, he’s more likely to groom mine in return”—which is true; chimps form mutual grooming partnerships that are relatively stable over the course of their lives. At first blush, then, social grooming seems like an act of hygiene, a way to keep one’s fur clean.

  This is far from the complete picture, however. We can’t take social grooming at face value. There are some puzzling facts that cast doubt on the simple hygienic function:

  •Most primates spend far more time grooming each other than necessary for keeping their fur clean.3 Gelada baboons, for example, devote a whopping 17 percent of their daylight hours to grooming each other.4 Clearly this is overkill, as some primate species spend only 0.1 percent of their time grooming each other, while birds spend maybe 0.01 percent of their time on similar preening behaviors.5

  •Even more puzzling is the fact that primates spend a lot more time grooming each other than they spend grooming themselves.6 If the only purpose of grooming were hygiene, we’d expect to see more self-grooming in proportion to social grooming.

  •Finally, we can correlate the average body size (of each primate species) with the amount of time they spend grooming. If grooming were strictly a hygienic activity, we’d expect larger species—those with more fur—to spend more time grooming each other. But in fact there’s no correlation.7

  We might ask ourselves, “What’s going on here?” There must be some other function at play.

  The primatologist Robin Dunbar has spent much of his career studying social grooming, and his conclusion has since become the consensus among primatologists. Social grooming, he says, isn’t just about hygiene—it’s also about politics. By grooming each other, primates help forge alliances that help them in other situations.

  An act of grooming conveys a number of related messages. The groomer says, “I’m willing to use my spare time to help you,” while the groomee says, “I’m comfortable enough to let you approach me from behind (or touch my face).” Meanwhile, both parties strengthen their alliance merely by spending pleasant time in close proximity. Two rivals, however, would find it hard to let their guards down to enjoy such a relaxed activity.8

  The bottom line: “Grooming,” says Dunbar, “creates a platform off which trust can be built.”9

  This political function of grooming helps explain other data points that don’t make sense according to the strictly hygienic function. For example, it explains why higher-ranked individuals receive more grooming than lower-ranked individuals.10 When low-ranking primates choose to groom one of their superiors, they’re less likely to be groomed in return—so they must be angling for some other kind of benefit (rather than simple reciprocity). Indeed, grooming partners are more likely to share food,11 tolerate each other at feeding sites,12 and support each other during confrontations with other members of the group.13

  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.14 Larger groups have, on average, greater political complexity, making alliances more important but also harder to maintain.

  Note that these primates don’t need to be conscious of their political motivations. As far as natural selection is concerned, all that matters is that primates who do more social grooming fare better than primates who do less. Primates are thereby endowed with instincts that make them feel good when they groom each other, without necessarily understanding why they feel good.15

  It’s also important to note that there’s still some role for hygiene in explaining why primates groom each other. If hygiene were completely irrelevant, primates would simply give each other back massages instead of picking through each other’s fur. But even though there’s some hygienic value to social grooming, it doesn’t explain why primates spend so much time doing it. Gelada baboons, for example, might be able to keep their fur clean with only 30 minutes of social grooming every day, but instead they spend 120 minutes. (This seems similar to a human showering four times a day.) Only politics explains why the geladas spend those additional, seemingly unnecessary 90 minutes.

  COMPETITIVE ALTRUISM

  Before we move on to human behavior, here is one more quick example.

  The Arabian babbler, famously studied by Amotz Zahavi and a team of ornithologists at Tel Aviv University, is a small brown bird that lives in the arid brush of the Sinai Desert and parts of the Arabian Peninsula. Babblers live in small groups of 3 to 20 members who collectively defend a small territory of trees, shrubs, and bushes that provide much-needed cover from predators. Babblers who live as part of a group do well for themselves, whereas those who are kicked out of a group are in great danger. They’re typically badgered away from other groups, have trouble finding food and shelter, and often fall prey to hawks, raptors, and snakes.16

  The social life of the babbler is rather curious. For simplicity, we’ll focus on the males, but similar behaviors can be fo
und among the females. Male babblers arrange themselves into rigid dominance hierarchies. The alpha male, for example, consistently wins in small squabbles with the beta male, who in turn consistently wins against the gamma male. Very occasionally, a much more intense fight erupts between two babblers of adjacent rank, resulting in one babbler’s death or permanent ejection from the group. Most of the time, however, the males get along splendidly with each other. In fact, they frequently help one another and the group in a variety of ways. Adults donate food to each other, bring food to their communal nestlings, attack predators and members of rival groups, and stand “guard duty” to watch for predators while the others look for food.

  At first glance, these activities appear straightforwardly altruistic (i.e., self-sacrificing). A babbler who takes a stint at guard duty, for example, foregoes his own opportunity to eat. Likewise, a babbler who attacks an enemy assumes risk of serious personal injury. On more careful inspection, however, these activities turn out not to be as selfless as they seem.

  First of all, babblers compete to help each other and the group—often aggressively so. For example, not only do higher-ranked babblers give food to lower-ranked babblers, sometimes they force it down the throats of unwilling birds! Similarly, when a beta male is standing guard duty at the top of a tree, the alpha will often fly up and harass the beta off his perch. The beta, meanwhile, isn’t strong enough to bully the alpha from guard duty, but he will often stand insistently nearby, offering to take over if the alpha male allows it. Similar jockeying takes place for the “privilege” of performing other altruistic behaviors.

  If the goal of these behaviors is to be helpful, why do the babblers waste effort competing to perform them? One hypothesis is that higher-ranked babblers are stronger, and therefore better able to forego food and fight off predators. And so, by taking on more of the burden (even if they have to fight for it), they’re actually helping their weaker groupmates. The problem with this hypothesis is that babblers compete primarily with the birds immediately above or below them in the hierarchy. The alpha male, for example, almost never tries to replace the gamma male from guard duty; instead the alpha directs all of his competitive energies toward the beta. If the goal were to help weaker members, the alpha should be more eager to take over from the gamma than from the beta. Even more damning is the fact that babblers often interfere in the helpful behaviors of their rivals, for example, by trying to prevent them from feeding the communal nestlings. This makes no sense if the goal is to benefit the group as a whole.

  So if these activities aren’t altruistic, what’s the point? What’s in it for the individual babbler who competes to do more than his fair share of helping others?

  The answer, as Zahavi and his team have carefully documented, is that altruistic babblers develop a kind of “credit” among their groupmates—what Zahavi calls prestige status. This earns them at least two different perks, one of which is mating opportunities: Males with greater prestige get to mate more often with the females of the group. A prestigious alpha, for example, may take all the mating opportunities for himself. But if the beta has earned high prestige, the alpha will occasionally allow him to mate with some of the females.17 In this way, the alpha effectively “bribes” the beta to stick around.

  The other perk of high prestige is a reduced risk of getting kicked out of the group. If the beta, for example, has earned lots of prestige by being useful to the group, the alpha is less likely to evict him. Here the logic is twofold. First, a prestigious beta has shown himself to be more useful to the group, so the alpha prefers to keep him around. Second, by performing more acts of “altruism,” a babbler demonstrates his strength and fitness. An alpha who goes beak-to-beak with a prestigious beta is less likely to win the fight, and so gives the beta more leeway than he would give a beta with lower prestige.

  Thus babblers compete to help others in a way that ultimately increases their own chances of survival and reproduction. What looks like altruism is actually, at a deeper level, competitive self-interest.

  HUMAN BEHAVIORS

  We can’t always take animal behavior at face value—that’s the main lesson to draw from the preceding examples. The surface-level logic of a behavior often belies deeper, more complex motives. And this is true even in species whose lives are much simpler than our own. So we can’t expect human behaviors, like voting or making art, to be straightforward either.

  Now, as we mentioned earlier, it would be a mistake to call these animal motives “hidden,” at least in the psychological sense. When baboons groom each other, they may happen not to be thinking about the political consequences (perhaps they’re simply acting on instinct), but their lack of awareness isn’t strategic. They have no need to conceal the political intentions underlying their grooming behavior, and thus no need to suppress their own knowledge. Knowledge suppression is useful only when two conditions are met: (1) when others have partial visibility into your mind; and (2) when they’re judging you, and meting out rewards or punishments, based on what they “see” in your mind.

  These two conditions may hold for nonhuman primates in some situations. In the moments leading up to a fight, for example, both animals are struggling frantically to decipher the other’s intentions.18 And thus there can be an incentive for each party to deceive the other, which may be facilitated by a bit of self-deception. Just as camouflage is useful when facing an adversary with eyes, self-deception can be useful when facing an adversary with mind-reading powers. But the mind-reading powers of nonhuman primates are weak compared to our own, and so they have less need to obfuscate the contents of their minds.

  We’ll discuss this more thoroughly in later chapters. But before moving on, there’s one last crucial point to make.

  When we study the behavior of other species, we can’t help putting ourselves in their shoes, in an attempt to feel what they feel and see the world through their eyes. But sometimes this method leads us astray, as when we find some animal behaviors “counterintuitive,” and in such cases, it says more about us than the species whose behavior we struggle to understand. For more than a century after Charles Darwin first published his theory, for example, scientists would often appeal to “the good of the species” in order to explain seemingly altruistic animal behaviors, like the babblers volunteering for guard duty.19 That’s certainly the kind of thing we might say if we were in the babblers’ shoes, but it’s not a valid naturalistic explanation—either for their behavior or for our own.

  To find out why we often misconstrue animal motives, including our own, we have to look more carefully at how our brains were designed and what problems they’re intended to solve. We have to turn, in other words, to evolution.

  2

  Competition

  Humans are a peculiar species. We’re relatively hairless, we walk on our hind legs, we dance and sing like nobody’s business. We laugh, blush, and shed tears. And our babies are among the most helpless in all the animal kingdom.

  But perhaps our most distinctive feature is our intelligence. Relative to our body size, we have unusually large brains. Partly because of this, we’re also the most behaviorally flexible creatures on the planet. But why are we so smart and flexible? And why did our brains grow so large, so quickly? (See Figure 2.)

  Figure 2. Human Ancestors’ Brain Volume Over Time (de Miguel and Henneberg 2001)

  Like the drunk who loses his keys and goes looking for them only under the streetlamp “because that’s where the light is,” people who study human evolution are more likely to search for explanations where the light (of evidence) is good. The archaeological record is biased toward objects that can endure, which means we get a pretty good picture of our ancestors’ skeletons, stone tools, and some of their body paint (red ocher). But we have almost no way to recover their brain tissue, vocalizations, or body language.

  This much is common sense. But in addition to biases in the evidence itself, we are also biased in the way we approach it. In this respect, we’re
not so much drunk as we are vain; we want our species to be seen in the most flattering light. There are facets of our evolutionary past that we spend less time poring over because we don’t like how they make us look. In this sense, our problem isn’t that the light is too dim, but that it’s too harsh.

  Consider these two broad “lights” where the keys to our big brains might be found:

  1.Ecological challenges, such as warding off predators, hunting big game, domesticating fire, finding new food sources, and adapting rapidly to new climates. These activities pit humans against their environment and are therefore opportunities for cooperation.

  2.Social challenges, such as competition for mates, jockeying for social status, coalition politics (alliances, betrayals, etc.), intra-group violence, cheating, and deception. These activities pit humans against other humans and are therefore competitive and potentially destructive.

  Many of us would prefer the keys to our intelligence to be found somewhere in the pleasing light of ecological challenges, implying that our extra gray matter evolved in service of cooperation. “We grew smarter,” the story would go, “so we could learn more, collaborate better against the harsh external world, and improve outcomes for everyone”: win-win-win.

  But many signs suggest that the keys to our intelligence lie in the harsh, unflattering light of social challenges, the arena of zero-sum games in which one person’s gain is another’s loss. It’s not that we’re completely unaware of these competitive, zero-sum instincts—we just tend to give them less prominence when explaining our behavior.

  It’s important to understand what we’re actually afraid of here. Many kinds of competition are actually easy for us to acknowledge, even celebrate. We love playful competition, for example, as in games and sports. “There are no losers in wrestling,” it’s sometimes said, “only winners and learners.” We also endorse competition in service of broader cooperative activities from which we all stand to gain, like when firms compete in the marketplace, driving down costs and spurring innovation. We’re even comfortable acknowledging group versus group competition, up to and including war. It’s not that we necessarily enjoy competing against other groups (although some of us do), but it isn’t awkward or uncomfortable to talk about—because competition against Them highlights the shared interests among Us. However destructive, war tends to bring a nation together.