AS A PULITZER PRIZE-WINNING AUTHOR and evolutionary psychologist at Harvard, Steven Pinker has already flexed his intellect in bringing us The Blank Slate: a very large treatment of human nature and the folly of intellectuals who try to deny its existence. In that book Pinker won round one: human nature is here to stay — even if it happens to be much less “determinative” of our behavior than many fear, it is far too important to ignore. The special targets for such enlightenment were a certain breed of intellectual, fairly rife in academia, who loves the idea of human possibilities being totally open and naively denies any major hint that genes might be constraining our behavior.
Pinker continues that same theme in his remarkable book Better Angels, an exceptionally well written evaluation of our political world that is driven by a controversial premise: that human beings are becoming less violent in their actual behavior. What drives us, as a species, to defy our better angels? Why do we have the capacity from one generation to the next to be cruel to animals, to beat and abuse spouses and children, to place costly acts of vengeance above acts of profitable cooperation, to engage in public acts of torture with or without guillotines, or to commit murder or mayhem or engage in full-scale war? This formidable list makes it seem quite logical to write off humanity as a species hopelessly given to violence, and as a species that, with two enormously destructive world wars under its belt just in the past century, surely must be getting worse instead of better.
Not so, Pinker tells us. He argues that we are in fact becoming less prone to these same practices, be it in the practice of warfare, or in our treatment of women or minorities, or in the vehemence with which we oppose torture in a political world in which many governments remain uninhibited. In a variety of ways, violence is on the decline in this violent-seeming world of ours — in spite of an astoundingly ugly first half of the twentieth century.
To back up this claim, Pinker uses a unique metric for how to evaluate rates of violence. In spite of the difficulty of measuring past violence quantitatively, an enormous amount of research effort has gone into the task, and Pinker’s mission is to add up all the facts. For his analysis, Pinker has decided to “normalize” our violent track record, in the sense that the quantitative measure is not simply how many people are killed in a given year in warfare. Rather such figures are corrected to reflect how many people were available to be killed, so that a ratio can be identified. This yields a rate, in terms of the number of people killed per thousand per population, and that proportion is what Pinker uses as he assesses patterns of violence over time. His analysis holds that rates of violence per capita are declining significantly, and the figures certainly support his thesis. Surprisingly, he says, they have been declining ever since Paleolithic hunter-gatherers developed even higher rates than modern nations.
This might be quite surprising to anyone save for an evolutionary anthropologist like myself. I already knew that hunter-gatherers, even those lacking any semblance of intensive warfare, tend to have internal homicide rates as high as Los Angeles or New York on a Saturday night. What I didn’t know was that the Mongol Conquest killed the same number of people as died in World War Two, but if you turn the killing into rates per thousand people, then proportionately the Second World War killed five times fewer people. This statistical adjustment is the basis for the primary claim of this book: that warfare is declining.
How does one explain a decline in per capita violence when weapons have been improving so drastically over time? One factor might be the incredible success of battlefield surgeons, but it is not just warfare that Pinker is talking about: it’s violence overall. To explain this overall trend, Pinker looks to Enlightenment humanism as a “civilizing” process. He combines the resulting general distaste for violence, which arose in centuries-ago books on etiquette for the upper classes and then filtered down to the rank and file, with the fact that as tribalism and petty fiefdoms declined they were replaced by the rise of larger polities whose rulers were more interested in making money than in violently protecting their honor. To back up this new ideology, they had gained sufficient centralized power to quell violence within their large realms. In effect, an age of economically irrational, quick-triggered knightly heroes gave way to an age of political businessmen who knew when it was rational to fight; the result was far less fighting.
Is this a brand new idea? Strictly speaking, the decline of violence — with a civilizing process as the agency — is not original with Pinker; a few academics have already ploughed that ground. What is original is his vision of the larger problem, and the all but superhuman amount of research that has gone into a topic that is both huge in scope and enormously important. In most circles, by going against received wisdom, Pinker’s hypothesis will seem counterintuitive, at least until one considers the facts. Good science often is counterintuitive; that’s its beauty. I would count this as good science, for the facts are sound and the author’s biases are stated up front. It also can be counted as good history written by a scientist, and because Pinker is an evolutionary psychologist the history is natural, in a Darwinian sense. By that I mean that ancestral dispositions and hunter-gatherer patterns are brought into the picture.
There is an obvious nagging concern to be considered when reading this book. We all know that the past century and beyond was extremely violent and destructive, with its two world wars and genocidal dictators taking us from the Holocaust to Hiroshima. Next came Korea and Vietnam and Pol Pot and Augusto Pinochet, later 9/11 and the invasions of Iraq and Afghanistan, and now the brutal suppression of the Arab Spring in Yemen and especially Syria. It’s difficult to imagine that the world is more peaceful now than it has been in years, and that violence is on the decline. But Pinker argues that in fact we have enjoyed for almost 70 years what he calls a Long Peace, and he attributes this to a decline in all-out nation-to-nation warfare on account of nuclear standoffs. Thanks to the law of mutually assured destruction, nations have been afraid of direct warfare, and have settled into more strategic and surgical conflicts that lead to far fewer casualties. We may ask: what would have happened to this recent world of ours if the atoms of Los Alamos had proven to be unsplittable? It stands to reason that land wars would have continued, and indeed the Korean and Vietnam wars were quite costly and highly destructive to life. On the other hand, neither developed into the kind of global conflict we experienced in 1916 and 1939, and this was likely a function of nuclear stalemate.
The Better Angels is not just about statistical trends; it’s about a theory that makes sense of trends. Political trends are notoriously difficult to predict, even with the advantage of knowing the history, and certainly it is all but mind-boggling to try to imagine the political course of our world had there been no nukes and a very bloody conventional assault on the Island of Japan. It seems likely that a really major Communist/Socialist versus Capitalist land war could have erupted, with the destructive power of vast economies making for record devastation in absolute terms, and at least a solid continuation of global violence in Pinker’s quantitative terms of deaths per thousand.
What actually took place sent us on a course unknown to human political history. While the devastation at Hiroshima and Nagasaki was basically in the same ballpark as conventional bombing raids on Nanking, London Dresden, and Tokyo (especially the last two, where the losses of life were equaled), the postwar advent of hydrogen bombs did change the name of the game. Suddenly the world was faced with mutually assured total destruction for both parties to the exchange — and for everyone else, a seriously imperiled and perhaps unlivable planet. To the extent that the same practical economic principles that saved medieval Europeans from continuous feudal slaughter over honor operate with nations today, mutually assured destruction does work as a deterrent. And the greater the bomb-holding nations’ populations and infrastructures, the more they have to lose — and the safer we all are.
However, I think that Pinker may overestimate the predictability of the threat of imminent and total destruction as a deterrent to warfare. His relative complacency in this respect could be the flaw in this book. If one were to adopt a different statistical approach, and talk about the progression of potential damage from warfare violence over time, things have definitely worsened since the time of the Mongol Conquest, and ever since 1945, when there existed just a few atomic bombs. Since the 1950s the potential for world destruction has changed exponentially, even though the threat’s very destructiveness serves as a deterrent. By this additional measure, the rate of potential human violence has actually gone over the top as proliferation continues.
Thus, while our global per capita rates of violence in fact have declined nicely along a wide variety of fronts, in the one area of warfare the possibility of world-ending violence has actually risen, and risen dramatically. This risk involves a probabilistic reality that I would like to have seen more fully taken into account, in this excellent and important book.