The decline of violence may be the most significant and least appreciated development in the history of our species. Its implications touch the core of our beliefs and values—for what could be more fundamental than an understanding of whether the human condition, over the course of its history, has gotten steadily better, steadily worse, or has not changed? Hanging in the balance are conceptions of a fall from innocence, of the moral authority of religious scripture and hierarchy, of the innate wickedness or benevolence of human nature, of the forces that drive history, and of the moral valuation of nature, community, tradition, emotion, reason, and science. My attempt to document and explain declines of violence has filled many pages, and this is not the place to fill many more in exploring their implications.
But I will end with two reflections on what one might take away from the historical decline of violence. The first concerns the way we should view modernity—the transformation of human life by science, technology, and reason, with the attendant diminishment of custom, faith, community, traditional authority, and embeddedness in nature. A loathing of modernity is one of the great constants of contemporary social criticism.
Whether the nostalgia is for small-town intimacy, ecological sustainability, communitarian solidarity, family values, religious faith, primitive communism, or harmony with the rhythms of nature, everyone longs to turn back the clock. What has technology given us, they say, but alienation, despoliation, social pathology, the loss of meaning, and a consumer culture that is destroying the planet to give us McMansions, SUVs, and reality television? Lamentations of a fall from Eden have a long history in intellectual life, as the historian Arthur Herman has shown in The Idea of Decline in Western History. And ever since the 1970s, when romantic nostalgia became the conventional wisdom, statisticians and historians have marshaled facts against it. The titles of their books tell the story: The Good News Is the Bad News Is Wrong, It’s Getting Better All the Time, The Good Old Days—They Were Terrible!, The Case for Rational Optimism, The Improving State of the World, The Progress Paradox, and most recently, Matt Ridley’s The Rational Optimist and Charles Kenny’s Getting Better.
These defenses of modernity recount the trials of daily living before the advent of affluence and technology. Our ancestors, they remind us, were infested with lice and parasites and lived above cellars heaped with their own feces. Food was bland, monotonous, and intermittent. Health care consisted of the doctor’s saw and the dentist’s pliers. Both sexes labored from sunrise to sundown, whereupon they were plunged into darkness. Winter meant months of hunger, boredom, and gnawing loneliness in snowbound farmhouses. But it was not just mundane physical comforts that our recent ancestors did without. It was also the higher and nobler things in life, such as knowledge, beauty, and human connection.
Until recently most people never traveled more than a few miles from their place of birth. Everyone was ignorant of the vastness of the cosmos, the prehistory of civilization, the genealogy of living things, the genetic code, the microscopic world, and the constituents of matter and life. Musical recordings, affordable books, instant news of the world, reproductions of great art, and filmed dramas were inconceivable, let alone available in a tool that can fit in a shirt pocket.
When children emigrated, their parents might never see them again, or hear their voices, or meet their grandchildren. And then there are modernity’s gifts of life itself: the additional decades of existence, the mothers who live to see their newborns, the children who survive their first years on earth. When I stroll through old New England graveyards, I am always struck by the abundance of tiny plots and poignant epitaphs. “Elvina Maria, died July 12, 1845; aged 4 years, and 9 months. Forgive this tear, a parent weeps. ‘Tis here, the faded floweret sleeps.” Even with all these reasons why no romantic would really step into a time machine, the nostalgic have always been able to pull out one moral card: the profusion of modern violence. At least, they say, our ancestors did not have to worry about muggings, school shootings, terrorist attacks, holocausts, world wars, killing fields, napalm, gulags, and nuclear annihilation. Surely no Boeing 747, no antibiotic, no iPod is worth the suffering that modern societies and their technologies can wreak.
And here is where unsentimental history and statistical literacy can change our view of modernity. For they show that nostalgia for a peaceable past is the biggest delusion of all. We now know that native peoples, whose lives are so romanticized in today’s children’s books, had rates of death from warfare that were greater than those of our world wars.
The romantic visions of medieval Europe omit the exquisitely crafted instruments of torture and are innocent of the thirtyfold greater risk of murder in those times. The centuries for which people are nostalgic were times in which the wife of an adulterer could have her nose cut off, a seven-year-old could be hanged for stealing a petticoat, a prisoner’s family could be charged for easement of irons, a witch could be sawn in half, and a sailor could be flogged to a pulp. The moral commonplaces of our age, such as that slavery, war, and torture are wrong, would have been seen as saccharine sentimentality, and our notion of universal human rights almost incoherent. Genocide and war crimes were absent from the historical record only because no one at the time thought they were a big deal. From the vantage point of almost seven decades after the world wars and genocides of the first half of the 20th century, we see that they were not harbingers of worse to come, nor a new normal to which the world would grow inured, but a local high from which it would bumpily descend. And the ideologies behind them were not woven into modernity but atavisms that ended up in the dustbin of history.
The forces of modernity—reason, science, humanism, individual rights—have not, of course, pushed steadily in one direction; nor will they ever bring about a utopia or end the frictions and hurts that come with being human. But on top of all the benefits that modernity has brought us in health, experience, and knowledge, we can add its role in the reduction of violence.
To writers who have noticed declines of violence, the sheer abundance of them, operating on so many scales of time and magnitude, has an aura of mystery. James Payne wrote of a temptation to allude to “a higher power at work,” of a process that seems “almost magical.” Robert Wright nearly succumbs to the temptation, wondering whether the decline of zero-sum competition is “evidence of divinity,” signs of a “divinely imparted meaning,” or a story with a “cosmic author.” I can easily resist the temptation, but agree that the multiplicity of datasets in which violence meanders downward is a puzzle worth pondering. What do we make of the impression that human history contains an arrow? Where is this arrow, we are entitled to wonder, and who posted it? And if the alignment of so many historical forces in a beneficial direction does not imply a divine sign painter, might it vindicate some notion of moral realism—that moral truths are out there somewhere for us to discover, just as we discover the truths of science and mathematics? My own view is that the Pacifist’s Dilemma at least clarifies the mystery, and shows how the nonrandom direction of history is rooted in an aspect of reality that informs our conceptions of morality and purpose. Our species was born into the dilemma because our ultimate interests are distinct, because our vulnerable bodies make us sitting ducks for exploitation, and because the enticements to being the exploiter rather than the exploited will sentence all sides to punishing conflict.
Unilateral pacifism is a losing strategy, and joint peace is out of everyone’s reach. These maddening contingencies are inherent in the mathematical structure of the payoffs, and in that sense they are in the nature of reality. It is no wonder that the ancient Greeks blamed their wars on the caprice of the gods, or that the Hebrews and Christians appealed to a moralistic deity who might jigger the payoffs in the next world and thereby change the perceived incentive structure in this one.
Human nature, as evolution left it, is not up to the challenge of getting us into the blessedly peaceful cell in the upper left corner of the matrix. Motives like greed, fear, dominance, and lust keep drawing us toward aggression. And though a major workaround, the threat of tit-for-tat vengeance, has the potential to bring about cooperation if the game is repeated, in practice it is miscalibrated by self-serving biases and often results in cycles of feuding rather than stable deterrence.
But human nature also contains motives to climb into the peaceful cell, such as sympathy and self-control. It includes channels of communication such as language. And it is equipped with an open-ended system of combinatorial reasoning. When the system is refined in the crucible of debate, and its products are accumulated through literacy and other forms of cultural memory, it can think up ways of changing the payoff structure and make the peaceful cell increasingly attractive. Not least among those tactics is the super-rational appeal to another abstract feature of reality: the interchangeability of perspectives, the non-specialness of our parochial vantage points, which corrodes the dilemma by blending the payoffs of the two antagonists.
Only an inflated sense of our own importance could turn our desire to escape the Pacifist’s Dilemma into a grand purpose of the cosmos. But the desire does seem to tap into contingencies of the world that are not exactly physical, and so it is different from the desires that were the mothers of other inventions such as refined sugar or central heating.
The maddening structure of a Pacifist’s Dilemma is an abstract feature of reality. So is its most comprehensive solution, the interchangeability of perspectives, which is the principle behind the Golden Rule and its equivalents that have been rediscovered in so many moral traditions. Our cognitive processes have been struggling with these aspects of reality over the course of our history, just as they have struggled with the laws of logic and geometry.
Though our escape from destructive contests is not a cosmic purpose, it is a human purpose. Defenders of religion have long claimed that in the absence of divine edicts, morality can never be grounded outside ourselves. People can pursue only selfish interests, perhaps tweaked by taste or fashion, and are sentenced to lives of relativism and nihilism. We can now appreciate why this line of argument is mistaken. Discovering earthly ways in which human beings can flourish, including stratagems to overcome the tragedy of the inherent appeal of aggression, should be purpose enough for anyone.
It is a goal that is nobler than joining a celestial choir, melting into a cosmic spirit, or being reincarnated into a higher life-form, because the goal can be justified to any fellow thinker rather than being inculcated to arbitrary factions by charisma, tradition, or force. And the data we have seen in this book show that it is a goal on which progress can be made—progress that is halting and incomplete, but unmistakable nonetheless.
A final reflection. In writing this book I have adopted a voice that is analytic, and at times irreverent, because I believe the topic has inspired too much piety and not enough understanding.
But at no point have I been unaware of the reality behind the numbers. To review the history of violence is to be repeatedly astounded by the cruelty and waste of it all, and at times to be overcome with anger, disgust, and immeasurable sadness. I know that behind the graphs there is a young man who feels a stab of pain and watches the life drain slowly out of him, knowing he has been robbed of decades of existence. There is a victim of torture whose contents of consciousness have been replaced by unbearable agony, leaving room only for the desire that consciousness itself should cease. There is a woman who has learned that her husband, her father, and her brothers lie dead in a ditch, and who will soon “fall into the hand of hot and forcing violation.” It would be terrible enough if these ordeals befell one person, or ten, or a hundred. But the numbers are not in the hundreds, or the thousands, or even the millions, but in the hundreds of millions—an order of magnitude that the mind staggers to comprehend, with deepening horror as it comes to realize just how much suffering has been inflicted by the naked ape upon its own kind. Yet while this planet has gone cycling on according to the fixed law of gravity, that species has also found ways to bring the numbers down, and allow a greater and greater proportion of humanity to live in peace and die of natural causes. For all the tribulations in our lives, for all the troubles that remain in the world, the decline of violence is an accomplishment we can savor, and an impetus to cherish the forces of civilization and enlightenment that made it possible.