Behave: The Biology of Humans at Our Best and Worst

by Robert M. Sapolsky

  Predictably, this has drawn fire from all sides. The Left charges that this giddy overvaluing of the dead-white-male Enlightenment fuels Western neoimperialism.4 My personal political instincts run in this direction. Nonetheless, one must admit that the countries with minimal violence, extensive social safety nets, few child brides, numerous female legislators, and sacrosanct civil liberties are usually direct cultural descendants of the Enlightenment.

  Meanwhile, the Right claims that Pinker ignores religion, pretending that decency was invented in the Enlightenment.5 He is eloquently unapologetic about this—for him much of what has gone right reflects people’s “shifting from valuing souls to valuing lives.” For others the criticism is that this escalator of reasoning fetishizes cognition over affect—after all, sociopaths have great Theory of Mind, a (damage-induced) purely rational mind makes abhorrent moral judgments, and a sense of justice is fueled by the amygdala and insula, not the dlPFC. Obviously, this many pages into the book, I feel that the interaction of reasoning and feeling is key.

  Have People Really Gotten Less Awful?

  This has been very contentious. Pinker offers the sound bite “We may be living in the most peaceful era in our species’ existence.” The fact most driving this optimism is that, except for the Balkan wars, Europe has been at peace since 1945, the longest stretch in history. For Pinker, this “Long Peace” represents the West coming to its senses after the ruin of World War II, seeing how the advantages of being a common market outweigh those of being a perpetually warring continent, plus some expanding empathy thrown in on the side.

  Critics characterize this as Eurocentrism. Western countries may kumbaya one another, but they’ve sure made war elsewhere—France in Indochina and Algeria, Britain in Malaya and Kenya, Portugal in Angola and Mozambique, the USSR in Afghanistan, the United States in Vietnam, Korea, and Latin America. Moreover, parts of the developing world have been continuously at war for decades—consider the eastern Congo. Most important, such wars have been made bloodier because the West invented the idea of having client states fight proxy wars for them. After all, the late twentieth century saw the United States and USSR arm the warring Somalia and Ethiopia, only to switch to arming the other side within a few years. The Long Peace has been for Westerners.

  The claim of violence declining steadily over the last millennium also must accommodate the entire bloody twentieth century. World War II killed 55 million people, more than any conflict in history. Throw in World War I, Stalin, Mao, and the Russian and Chinese civil wars, and you’re up to 130 million.

  Pinker does something sensible that reflects his being a scientist. He corrects for total population size. Thus, while the eighth century’s An Lushan Rebellion and civil war in Tang dynasty China killed “only” 36 million, that represented one sixth of the world’s population—the equivalent of 429 million in the midtwentieth century. When deaths are expressed as a percentage of total population, World War II is the only twentieth-century event cracking the top ten, behind An Lushan, the Mongol conquests, the Mideast slave trade, the fall of the Ming dynasty, the fall of Rome, the deaths caused by Tamerlane, the annihilation of Native Americans by Europeans, and the Atlantic slave trade.

  Critics have questioned this—“Hey, stop using fudge factors to somehow make World War II’s 55 million dead less than the fall of Rome’s 8 million.” After all, 9/11’s murders would not have evoked only half as much terror if America had 600 million instead of 300 million citizens. But Pinker’s analysis is appropriate, and analyzing rates of events is how you discover that today’s London is much safer than was Dickens’s or that some hunter-gatherer groups have homicide rates that match Detroit’s.

  But Pinker failed to take things one logical step further—also correcting for differing durations of events. Thus he compares the half dozen years of World War II with, for example, twelve centuries of the Mideast slave trade and four centuries of Native American genocide. When corrected for duration as well as total world population, the top ten now include World War II (number one), World War I (number three), the Russian Civil War (number eight), Mao (number ten), and an event that didn’t even make Pinker’s original list, the Rwandan genocide (number seven), where 700,000 people were killed in a hundred days.*

  This suggests both good and bad news. Compared with the past, we are extraordinarily different in terms of whom we extend rights to and feel empathy for and what global ills we counter. And things are better in terms of fewer people acting violently and societies attempting to contain them. But the bad news is that the reach of the violent few is ever greater. They don’t just rage about events on another continent—they travel there and wreak havoc. The charismatically violent inspire thousands in chat rooms instead of a mob in their village. Like-minded lone wolves more readily meet and metastasize. And the chaos once let loose with a cudgel or machete occurs now with an automatic weapon or bomb, with far more horrific consequences. Things have improved. But that doesn’t mean they’re good.

  Thus we now consider insights provided by this book that might help.

  SOME TRADITIONAL ROUTES

  First there’s the strategy for reducing violence that stretches back tens of thousands of years—moving. If two individuals in a hunter-gatherer band are having tensions, one frequently shifts to a neighboring band, sometimes voluntarily, sometimes not. Similarly, interband tensions are reduced when one shifts to a different location, an advantage of nomadicism. A recent study of the hunter-gathering Hadza of Tanzania showed an additional benefit to this fluidity straight out of chapter 10. Specifically, it facilitates highly cooperative individuals associating with one another.6

  Then there are the beneficial effects of trade, as emphasized by anthropologists, as well as Pinker. From trading at a village market to signing international trade agreements, it is often true that where goods do not pass frontiers, armies will. It’s a version of Thomas Friedman’s somewhat tongue-in-cheek Golden Arches Theory of peace—countries with McDonald’s don’t fight one another. While there are exceptions (e.g., the U.S. invasion of Panama, the Israeli invasion of Lebanon), Friedman’s broad point holds—countries that are sufficiently stable that they are integrated into global markets with the likes of McDonald’s and prosperous enough that their people keep those establishments in business likely conclude that the trade advantages of peace outweigh the imagined spoils of war.**7

  This isn’t surefire—for example, despite being major trading partners, Germany and the UK fought World War I—and there’s no shortage of people willing to go to war, even at the cost of disrupted trade and scarce commodities. Moreover, “trade” is double-edged. It’s certifiably groovy when occurring between indigenous rain forest hunters; it’s certifiably vile if you’re protesting the WTO. But as long as countries can wage war on distant nations, long-distance trade that makes them interdependent is a good deterrent.

  Cultural diffusion in general (which includes trade) can also facilitate peace. This can have a modern tint—across 189 countries, digital access predicts increased civil liberties and media freedom. Moreover, the more civil liberties in a neighboring country, the stronger this effect, as ideas flow with goods.8

  Religion

  Well, I’d love to skip this section, but I can’t. That’s because religion is arguably our most defining cultural invention, an incredibly powerful catalyst for both our best and worst behaviors.

  When introducing the pituitary in chapter 4, I didn’t feel obliged to first disclose my feelings about the gland. But the equivalent feels appropriate here. Thus: I was raised highly observant and Orthodox, felt intensely religious. But then, around age thirteen, the whole edifice collapsed; ever since, I’ve been incapable of any religiosity or spirituality and more readily focus on religion’s destructive than its beneficial aspects. But I like being around religious people and am moved by them—while baffled by how they can believe that stuff. And I fervently wish that I could. The e
nd.

  As emphasized in chapter 9, we’ve created a staggering variety of religions. In considering solely religions with worldwide reaches, there are some important commonalities:

  They all involve facets of religiosity that are intensely personal, solitary, and individualized, as well as facets that are about community; as we’ll see, these are very different realms when it comes to fostering our best and worst behaviors.

  All involve personal and communal ritualized behaviors that comfort in times of anxiety; however, many of those anxieties were created by the religion itself. The anxiety-reducing effects of belief are logical, given that psychological stress is about lack of control, predictability, outlets, and social support. Depending on the religion, belief brings an explanation for why things happen, a conviction that there is a purpose, and the sense of a creator who is interested in us, who is benevolent, who responds to human entreaties, who preferentially responds to entreaties from people like you. No wonder religiosity has health benefits (independent of the community support that it brings and the decreased rates of substance abuse).

  Recall the role of the anterior cingulate cortex (ACC) in sounding an alarm when there is a discrepancy between how you thought things worked and how they actually do. After controlling for personality and cognitive abilities, more religious people show less ACC activation when getting news of a negative discrepancy. Other studies show the anxiety-reducing effects of repetitive religious rituals.9

  Finally, all the world religions distinguish between Us and Them, though they differ as to what is required to be an Us and whether the pertinent attributes are immutable.

  Enough is known about the neurobiology of religiosity that there’s even a journal called Religion, Brain and Behavior. Reciting a familiar prayer activates mesolimbic dopaminergic systems. Improvising one activates regions associated with Theory of Mind, as you try to understand a deity’s perspective (“God wants me to be humble in addition to grateful; better make sure I mention that”). Moreover, more activation of this Theory of Mind network correlates with a more personified image of a deity. Believing that someone is faith healing deactivates the (cognitive) dlPFC, suspending disbelief. And performing a familiar ritual activates cortical regions associated with habit and reflexive evaluation.10

  So are religious people nicer than nonreligious ones? It depends on whether they’re interacting with in- or out-group members. Okay, are religious people nicer to in-group members? Numerous studies say yes—more volunteering (with or without a religious context), charitable giving, and spontaneous prosociality, more generosity, trust, honesty, and forgiveness in economic games. However, numerous studies show no differences.11

  Why the discrepancy? For starters, it matters whether data are self-reported—religious people tend to inflate reports of their prosociality more than do nonreligious people. Another factor is whether the prosociality is public—conspicuous display is particularly important to those religious people who strongly need social approval. As more context dependency, in one study religious people were more charitable than nonreligious ones—but only on their Sabbath.12

  Another important issue: what kind of religion? As introduced in chapter 9, Ara Norenzayan, Azim Shariff, and Joseph Henrich of the University of British Columbia have identified links between features of various religions and aspects of prosociality.13 As we saw, small-band cultures (such as hunter-gatherers) rarely invent moralizing deities. It is not until cultures are large enough that people regularly interact anonymously with strangers that it becomes commonplace to invent a judgmental god—the Judeo-Christian/Muslim deity.

  In such cultures overt and subliminal religious cues boost prosociality. In one study religious subjects unscrambled sentences that did or didn’t contain religious terms (e.g., spirit, divine, sacred); doing the former prompted generosity afterward. This is reminiscent of chapter 3’s finding that merely seeing a pair of eyes posted on a wall makes people more prosocial. And showing that this is about being monitored, unscrambling sentences with secular terms such as “jury,” “police,” or “contract” had the same effect.14

  Thus reminders of a judgmental god(s) boosts prosociality. It also matters what that deity does about transgressions. Within and among cultures, the more punitive the god, the more generosity to an anonymous coreligionist. Do punitive gods make for more punitive people (at least in an economic game)? In one study, no—save your cash, God’s got it covered. In another, yes—a punitive god would want me to be punitive as well. The UBC group has shown something ironic. Priming people to think of God as punitive decreases cheating; thinking of God as forgiving increases it. The researchers then studied subjects from sixty-seven countries, considering the prevalence in each of belief in the existence of a heaven and hell. The greater the skew toward belief in hell, rather than heaven, the lower the national crime rate. When it comes to Eternity, sticks apparently work better than carrots.

  And what about religion facilitating the worst in us, with respect to Thems? Well, one piece of evidence for this is, uh, like, human history. Every major religion has historical blood on its hands—Buddhist monks led the persecution of Rohingya Muslims in Burma, and a Quaker in the White House oversaw the carpet bombing of North Vietnam for Christmas.*15 This ranges from religious wars, which are, to cite a quote generally attributed to Napoleon, “people killing each other over who has the better imaginary friend,” to secular ones where, nevertheless, omniscient support is requested and proclaimed. Religion is a particularly tenacious catalyst of violence. Catholics and Protestants have been killing each other in Europe for nearly 500 years, Shiites and Sunnis for 1,300. Violent disagreements about differing economic or governmental models never last as long—this would be like people still killing each other today over, say, Eastern Roman Emperor Heraclius’s 610 decision to switch the official language from Latin to Greek. As shown in a study of six hundred terrorist groups spanning forty years, religiously based terrorism persists the longest and is least likely to subside due to fighters joining the political process.

  Religious primes foster out-group hostility. In a “field study” where people were surveyed in different locations in a cosmopolitan European city, merely walking past a church made Christians express more conservative, negative attitudes toward non-Christians. Another study examined the priming effects of a violent god. Subjects read a Bible passage in which a woman is murdered by a mob from another tribe. Her husband consults with his tribesmen and forms an army that takes revenge by attacking the other tribe (in biblical fashion, destroying their cities and killing every human and animal). Half the subjects were told this story. In the story told to the other half, while contemplating revenge, the army asks for advice from God, who sanctions them to majorly chasten the other tribe.16

  Visit bit.ly/2mNNLLf for a larger version of this graph.

  Participants then played a competitive game in which each round’s loser was blasted with a loud noise at a volume chosen by the other player. Reading the scene where God sanctions their desire for violence increased the volume with which opponents were chastened.

  No surprise: the effect was bigger in males than in females. Big surprise: subjects were either devout Mormons at Brigham Young University or students of typically liberal religions at a Dutch university, and the effect was equally strong in both groups. Biggest surprise: even among subjects who did not subscribe to the Bible (a surprisingly high 1 percent of the Brigham Young students and 73 percent of the Dutch), godly sanction increased their aggressiveness (though to a lesser extent). Thus, divine sanction of violence can increase aggression even in people whose religiosity probably doesn’t include a vengeful god, as well as among those who don’t even believe there’s divine anything.

  Of course, this is not a uniform effect of religion; Norenzayan distinguishes between private and communal religiosity in surveying support for suicide bombers among Palestinians.17 In a refutatio
n of “Islam = terrorism” idiocy, people’s personal religiosity (as assessed by how often they prayed) didn’t predict support for terrorism. However, frequently attending services at a mosque did. The author then polled Indian Hindus, Russian Orthodox adherents, Israeli Jews, Indonesian Muslims, British Protestants, and Mexican Catholics as to whether they’d die for their religion and whether people of other religions caused the world’s troubles. In all cases frequent attendance of religious services, but not frequent prayer, predicted those views. It’s not religiosity that stokes intergroup hostility; it’s being surrounded by coreligionists who affirm parochial identity, commitment, and shared loves and hatreds. This is hugely important.

  —

  What should one make of these various findings? Religiosity isn’t going anywhere.* Given that, it seems that boosting in-group sociality is best done with a moralizing, punitive god. The standard, wearisome critique of atheism is that lack of a god(s) produces nihilistic amorality; the standard response is that it’s pretty unimpressive if you are kind only because you fear damnation. Unimpressive or not, it appears to be useful. The big challenge is when communal aspects of religiosity fuel out-group hostility. It’s useless to call for religions to broaden the extent of their Us-ness. Religions are quirky as to who is an Us, ranging from “only those who look, act, talk, and pray like people in our sect” to “all of life.” It will be discouragingly tough to shift religions from the former to the latter.