The Better Angels of Our Nature by Steven Pinker

We are currently living through the least violent period in the history of the human species. The 21st century has so far been less violent than the 20th, which in turn was less violent than the early industrial era, which in turn was less violent than the early modern era, which in turn was less violent than the Middle Ages, which in turn was less violent than the classical civilizations, which in turn was less violent than the world of hunter-gatherers. The long decline of violence of all types and all scales is perhaps the single most consequential and consistent macro-trend throughout human history.

Among hunter-gatherers, between 10% and 60% of all deaths were due to homicides, and most unearthed human remains from the era carry evidence of injuries from human-made weapons. In contrast, today’s developed countries have homicide rates as low as 1 per 100,000 people per year.

Humans are neither innately peaceful nor innately bloodthirsty. Violence in the animal kingdom is highly pragmatic. Natural selection has long rewarded individuals who can successfully deploy violence in the pursuit of selfish gain, self-defense, or credible deterrence. On the other hand, natural selection punishes individuals who needlessly endanger themselves by participating in pointless or futile fights.

Since violence is context-dependent, people can be nudged away from it. Human nature has changed little in the past few millennia, but observed human behavior has changed a great deal. Many developments throughout human history have significantly changed how people and groups relate to each other.

Whether driven by predation, dominance, revenge, sadism, or ideology, violence ultimately occurs because someone wants someone dead and is serious about following through. Even today, nearly all people sometimes have fantasies of committing violent acts, but these fantasies are increasingly likely to be overridden in their brains by other considerations, mainly self-control, empathy, morality, and reason.

Life in a state of nature

Nature is red in tooth and claw, and so were the lives of hunter-gatherer people who lived in small band societies. Hunter-gatherers often have peaceful reputations today, but much of this stems from low populations and low absolute numbers of violent acts. When adjusted for population size, hunter-gatherers had per-capita rates of violence that were hundreds or even thousands of times higher than modern societies.

The Hobbesian Trap

Hunter-gatherers lived in tight-knit groups with an internal dominance hierarchy and an ethic of communal sharing. However, interactions outside the group took place within a framework of lawless anarchy.

Neighboring groups often found themselves in a situation known as the Hobbesian Trap. Mutual peace is the best collective outcome, but mutual peace requires mutual trust that is not present between the groups. Placing trust in an untrustworthy neighbor and later getting betrayed is potentially ruinous, while the cost of being unnecessarily mistrustful is much lower. Both sides therefore have an individual incentive to defect rather than cooperate. Fearing the other side may attack them, both sides feel a temptation to strike pre-emptively, a prophecy of violence that can become self-fulfilling.

Hunter-gatherers lived in constant fear of raids and ambushes. While public declarations of war and pitched battles sometimes occurred, far more people were killed in surprise attacks. Mindful of the possibility of revenge, attackers were incentivized to kill not just their intended targets, but anyone who might potentially retaliate on the victim’s behalf. In the most severe cases of inter-tribal warfare, a group could end up wiping out another group completely, usually killing all its men while kidnapping the women as brides.

Cultures of honor

In a lawless world, the only available justice was self-help justice in the form of revenge. Human moral accounting is self-serving, so a victim of revenge is likely to see an act of revenge as an escalation rather than a tit-for-tat. Both sides of a feud develop divergent stories about it and at least one side may deem itself morally entitled to land another hit. Acts of revenge can escalate into self-perpetuating cycles.

The best strategy for deterring aggression and exploitation is to develop a fearsome reputation as someone who shouldn’t be messed with. Such a reputation requires a lot of effort and a lot of violence to maintain. It is not enough to simply retaliate harshly and decisively against anyone who harms you. You must also retaliate against any real or imagined insult against your reputation or public image; failure to do so may be seen as weakness. Cultures obsessed with personal honor consistently arise wherever the rule of law is weak. Rather than prevent conflict through deterrence, cultures of honor increase a society’s overall level of violence by raising the likelihood that a conflict will escalate into a multi-round feud.

Early states and the pacifying process

At different times in different places, humans shifted from hunting and gathering to agriculture on fixed settlements. This era saw the rise of the first governments and political states. Governments were not intentionally invented; they started off as protection rackets and then grew more sophisticated from there.

The Leviathan

Much as farmers have an incentive to break up fights between their animals, overlords who extort taxes have an incentive to break up fights between their subjects. From an overlord’s perspective, any unauthorized bloodshed is a pointless loss. Overlords can use the promise of defense against private aggression to shore up their political legitimacy. Overlords thus end up claiming a monopoly on the legitimate use of violence within their domain.

Governments are an example of a Leviathan, a bystander too powerful to try fighting directly. Leviathans intervene in private disputes from a position of disinterested neutrality, prohibiting and punishing all acts of private aggression. Whether this aggression takes the form of predation, pre-emptive strikes, or revenge, the aggressor’s excuse does not matter to the Leviathan. Leviathans punish aggressors to raise the cost of aggression and deter quarrels from starting. A Leviathan’s ruling marks the end of a dispute; victims are prohibited from privately seeking additional revenge outside of official channels. Killing your intended victim is no longer a way to pre-empt the possibility of revenge because the Leviathan will outlive the victim and retaliate on the victim’s behalf.

Governments drastically reduced violence by thwarting cycles of revenge before they could get underway. Early state societies enjoyed a reduction of violence of 80% or more relative to hunter-gatherers.

The brutality of early governments

Governments reduced violence significantly by banning private feuding and raiding, but these improvements were partially offset by a new category of violence: violence perpetrated by governments themselves. In matters of criminal law, enforcement was quite spotty, so governments compensated by making an example of anyone they caught. Mutilation, torture, and public executions were frontline punishments for most offenses, including many victimless crimes such as breaking religious taboos. The methods and devices used for punishments were far more creative and sadistic than anything used today.

Governments were only slightly better-armed than their citizens and they knew their position was fragile. Rulers used religion to justify their rule and brutally punished any political or religious dissent. Wary of arming their peasants, governments usually contracted mercenaries on a temporary basis rather than maintain standing armies.

The elite classes of society were every bit as violent as the lower classes, often even more so. All the early civilizations were hereditary monarchies that theoretically supported orderly transitions of power, but palace coups and violent inheritance disputes were the norm rather than the exception.

The Hobbesian world of international relations

Relationships between political states were Hobbesian in much the same way relationships between tribes had been in hunter-gatherer times. The agrarian economy was a zero-sum world in which a state’s wealth depended primarily on the land and natural resources it occupied. Virtually all rulers harbored dreams of territorial expansion and went to war constantly with their neighbors. War was glorified in government propaganda as a noble and heroic pursuit.

Ancient warfare was staggering in its savagery. In lieu of wages, governments often granted mercenaries the right to pay themselves by plundering their victims. Wars would often be what is now termed “total war”: scorched-earth tactics, no distinction between civilian and military targets, and genocidal massacres of entire populations. Rape and bride kidnapping by invading troops were considered legitimate spoils of war. Especially if the war was motivated by religion or some other ideological difference, diplomacy was often off the table.

Humans have a bias for overconfidence; in a social species, bluffing is more effective if you truly believe it yourself. In a world without overconfidence, no state would attack another unless victory was likely and profitable, losers would concede or flee as soon as defeat was obvious, and prolonged World War I-style wars of attrition would never occur. Instead, the real-life history of warfare is littered with delusional decisions by top commanders. Aggressor states lost anywhere between a quarter and half of the wars they initiated, and when they won the victories were often Pyrrhic.

A culture of hierarchy

The morality of agrarian cultures was built around respect for authority and tradition. Relationships of absolute and unaccountable power existed not just between rulers and their subjects, but also in private life. Family patriarchs were generally understood to own their wives, sons, and unmarried daughters. Slavery was common in ancient civilizations; owning human slaves was as morally uncontroversial as owning farm animals. Women, children, slaves, and farm animals were all widely mistreated and had no legal recourse.

Due to the uncertainty over paternity inherent to being male, men are evolutionarily hardwired to be possessive of their sexual partners and to feel implacable rage when their sexual exclusivity is violated. Male sexual jealousy was widely accommodated in society’s institutions to the detriment of women. The rape of a woman was treated as a tort against the woman’s owner (if enslaved), husband (if married), or male guardian (if unmarried) rather than as a criminal offense against the woman. Ancient civilizations widely practiced heavy-handed mate-guarding tactics such as veiling, chaperoning, sex-segregated spaces, different outfits for married versus unmarried women, female genital cutting, honor killings, and extreme criminal punishments for adulterous wives.

Early civilizations were often polygamous. Kings and emperors had up to hundreds of wives and concubines, whereas lords and noblemen could have up to dozens. It mathematically followed that there were plenty of angry lower-class men who had no marital or sexual prospects. Unmarried and underemployed men in the 15-30 age range have always been society’s biggest troublemakers, especially when they coalesced into gangs. Sending hopeless young men off to war was a convenient way for governments to get these men to do their troublemaking far from home.

Early signs of the civilizing process

Many ancient civilizations practiced the ritual sacrifice of livestock to proactively appease bloodthirsty gods, with a subset extending the practice to human sacrifice. However, many ancient civilizations later abandoned human sacrifice as they grew more secure and their worldview became less fatalistic. As the first barbaric cultural practice to go extinct, human sacrifice is an instructive case in how abolitions typically unfold. Abolition was widely recognized as a progressive act at the time it occurred, abolitionist cultures viewed non-abolitionist cultures as savage, the practice was forgotten by future generations despite once having been seen as essential to society, and no serious effort was ever made to reinstate it.

The agrarian economy rewarded diligence and long-term planning more than the hunter-gatherer lifestyle. As society became more hierarchical, appeasing authority figures became an essential life skill. These historical developments forced people to increasingly exercise skills such as self-control and empathy, which had the added bonus of reducing acts of impulsive violence. Even so, by modern sensibilities, most ancient people were rash, short-sighted, uncouth, animalistic, and emotionally volatile.

Early modernity and the humanitarian revolution

After a spurt of progress caused by governments pacifying their subjects, the world’s level of violence did not meaningfully fall for many millennia. Murder rates were 30-100 times higher than today and many new inter-state wars began each year. The arrival of the printing press, gunpowder weapons, and oceanfaring voyage technology to 15th century Europe was a jolt that inaugurated the modern era and brought significant changes to society.

The printing press and mass literacy

The invention of the printing press in 1450s Germany is arguably the most culturally consequential invention in history. Thanks to its ability to produce written texts at a high scale, the quantity and variety of published works suddenly exploded. The ability to read and write had once been an exceptionally rare skill, but now there was a much stronger incentive to learn it. Though literacy remained mostly limited to upper-class urban men for several centuries, it still had a profound impact on the attitudes of the ruling classes within Europe.

Modern-day educated people can hardly fathom how small the world is to an illiterate person. Illiterate people have no sources of worldly knowledge besides personal life experience and hearsay from their immediate social contacts. In contrast, literate people are capable of obtaining information from people far outside their usual social circle. Since writing summarizes experiences into a concise and digestible form, a literate person can gather far more knowledge than any person can realistically pick up from life experiences alone.

The act of reading forces the reader to temporarily take the perspective of the writer or the subject. Literacy caused people to grow their circle of empathy far outside the usual boundary of just kin and clan. Fictional stories led people to root for characters in life stations very different from their own. Memoirs showcased the world’s great diversity of cultures and life experiences, causing readers to look at human culture in a more detached and critical manner. Many written texts brought attention to the struggles and suffering of overlooked groups of people, often significantly changing public opinion.

The decline of superstition

Scientific knowledge grew alongside literacy. Many popular superstitions withered upon even the slightest skeptical scrutiny. A world with greater scientific literacy was a world with fewer justifications for violence. People increasingly understood that the universe operates on consistent physical laws rather than on the day-to-day whims of gods, spirits, and witches. From there, people internalized the idea that tragedies sometimes happen and that not every tragedy needs a villain. Accusations of witchcraft, a common justification for murder since hunter-gatherer times, died out among educated populations.

The era of mass literacy marked the start of the decline of organized religion as a foundational force in society. Religions had once had a near-total monopoly on society’s core narratives, but now they started weakening in the face of competition. Literate people were much less receptive to the idea that kings ruled by divine right, that suffering in this world is okay because it will be rewarded in the next, or that believers have a moral obligation to wage genocides against non-believers. Ancient religions didn’t die, but religion increasingly became a private personal matter. People continued to cite ancient religions as a source of morality, but they increasingly drew their real-life morality from Enlightenment-era sources.

An ethic of equality

The rise of mass-produced texts marked the beginning of a lively society-wide conversation about how society should be run, a conversation that has continued ever since. Unlike most illiterate people, educated people understand that all other people have a consciousness similar to their own, that people are fundamentally alike with a shared human nature, that much of human culture is arbitrary, that people’s perspectives are interchangeable, that all people are fallible, and that objective truth exists independently of an observer. Using these new statements as their foundations, thinkers set out to define systems of morals that could be justified through pure reason and that could apply across cultures.

The intellectual class’s ideology shifted towards what is today called classical liberalism. Classical liberalism says that individual human flourishing is the highest goal because no alternative goal can be clearly identified and defended. It therefore follows that society’s institutions should exist to serve people rather than the other way around. Classical liberalism also says that nobody has solid moral grounds for privileging their interests over those of other people; if you believe that people and perspectives are interchangeable, it is impossible to argue the opposite. It therefore follows that society should recognize reciprocity as the foundation of morality and recognize equality between people. Rather than base morality on tribalism, authority, and tradition, classical liberalism instead prizes individual autonomy, fairness, and reason.

Viewed from a classical liberal lens, many agrarian-era institutions were holdovers from history that no one would ever re-invent. Blatantly unfair institutions like absolute monarchy, hereditary castes, and chattel slavery proved to be impossible to defend without appealing to authority or tradition. Slavery in particular came under political attack and eventually got banned throughout the West.

Violence was increasingly seen as a social problem that could be reduced by designing human institutions more thoughtfully. The violence that governments could most easily control was their own. As the ruling classes adopted the view that the criminal justice system’s purpose is deterrence rather than sadistic revenge, governments became much less cruel. Torture was outlawed both as a punishment and as a valid way of extracting confessions. The death penalty was abolished for nearly all crimes short of murder and treason. Prolonged and torturous methods of execution were replaced with faster methods like beheading, hanging, and the firing squad. Imprisonment became the standard punishment for criminal offenses; the first prisons were squalid, but their living conditions improved over time. Crime did not rise in response to this new leniency; if anything, this new proportionality and self-restraint was helpful in legitimizing governments as fair.

The American and French Revolutions in the late 18th century featured humanity’s first ever attempts at designing governments from a blank slate. Both constitutions were based on classical liberal principles, featuring an elected legislature independent of the executive branch, a lack of a hereditary nobility, a system of checks and balances, and a list of baseline rights for all citizens. Throughout their relatively short history, democracies have consistently been less violent and warlike than non-democracies. Democracies are already in the habit of solving disagreements without violence and they often carry this habit forward into their dealings with other countries. Democracies have public and transparent decision-making, so their neighbors don’t live in fear of surprise pre-emptive strikes. Since the rewards of war go to the ruling classes and the costs are borne by ordinary people, voters in democracies are less likely than autocratic leaders to approve of war. No two mature democracies have ever gone to war with one another, though a few counterexamples exist among fledgling democracies. No democracy has ever committed a genocide against its own population.

Many millennia-old barbaric cultural practices rapidly died out during the Enlightenment and never returned. Some practices went from commonplace to controversial to contemptible to prohibited to unthinkable to forgotten in as little as a century. These social changes are especially notable because they happened during a time when the physical world changed relatively little; the economy was still pre-industrial, economic growth was still very slow, and most people were still extremely poor.

The consolidation of nation-states

Once gunpowder weapons entered the scene, ragtag militias were no longer a match against professional high-tech armies. Large countries could now swallow their smaller neighbors and become even larger. Several European countries expanded themselves even further by establishing colonies beyond Europe. From 1500 to 1900, the number of independent political states in Europe fell from about five thousand to about thirty. Inter-state wars became less numerous, but they also tended to become longer and deadlier when they occurred.

A new category of country began to emerge: the great power. Great powers were the countries capable of projecting force and influencing events well beyond their borders. Smaller countries that lived within a great power’s sphere of influence had a Leviathan-like protector and mediator, but relationships between great powers themselves have always been lawless and Hobbesian. Great powers have consistently gotten into wars more often than other countries.

As political states grew bigger and more organized, they could support economies of scale. Rather than mercenaries, states started using permanent standing armies staffed through conscription. Widely-recognized currencies and large-scale infrastructure projects made domestic commerce easier. Governments legitimized themselves by claiming to be the protector of a culture and ethnic group. Governments encouraged loyalty to the nation-state, expanding people’s notion of their in-group.

Industrialization and gentle commerce

With the Industrial Revolution, humanity began to escape the Malthusian trap. For all of history until this point, most people lived on the boundary of starvation and any economic surpluses were quickly cancelled out by population growth. Humanity became more prosperous, more dignified, and less fatalistic about the future. Suffering was increasingly seen as a problem to be solved rather than an inevitability to be glorified. As humanity’s conquest of the natural world grew ever more complete, a growing share of its problems became self-inflicted.

Make money, not war

Business relationships promoted peace by making people more useful to each other alive than dead. When buying something is cheaper and less risky than trying to steal it, people will opt to buy. It was not necessary to be chummy with one’s business partners, but it was in the interest of all sides to get along. Success in business required knowing that strangers wanted, which in turn required the use of empathy. Not all money-making was ethical, but the industrial-era pursuit of wealth was far less violent than the agrarian-era pursuit of honor and glory. Transactional relationships with strangers often felt emotionally cold, but these relationships were a step up from the callous indifference of the past.

A country’s wealth increasingly depended on the productivity of its workers rather than on its land. Even a small and resource-poor country could now become wealthy by building robust institutions and setting itself up as a hub for international commerce. Countries with high levels of imports and exports have consistently been less likely to go to war. The prospect of severed commercial ties made war unappealing for both businesses and consumers. Modern high-tech warfare was expensive, so land-grabbing invasions were no longer an economically-attractive proposition for governments.

Despite their anonymity, crowdedness, and cultural diversity, cities were usually less crime-ridden than rural areas on a per-capita basis. Urban police forces were well-equipped and well-organized. The abundance of employment opportunities offered lots of alternatives to a life of crime. Governments set up public schools that were compulsory and free, getting youngsters off the streets.

An industrialized world is a world where violence doesn’t pay and where most violence is not rational. Most murders in industrial societies are done for moralistic reasons such as revenge rather than for personal gain. Most inter-state wars in the past few centuries have been fought for ideological or nationalist reasons rather than for plunder.

A culture of self-control

Industrial society was full of traps and temptations, but also full of great rewards for the people who could resist them. Success in a commercial society required a long-term outlook and a disciplined approach to life.

Self-control and the ability to defer gratification became essential traits. Popular culture increasingly admired people who kept their composure in the face of provocation rather than people who lashed out. Self-control was not only correlated with lower rates of impulsive and regrettable violence, but also with economic success and overall well-being.

The decline of honor

Industrial-era people had far more social contacts than agrarian-era people. They belonged to many communities and had greater practical freedom to leave them for others. People’s social identities and social standing were no longer entirely defined by just one role. Since people now belonged to many dominance hierarchies rather than a single all-encompassing one, most interpersonal conflicts carried low stakes.

The centuries-old practice of people settling personal disputes by dueling died out during the 19th century. Dueling didn’t die because it was banned, as bans were widely disregarded. Dueling finally died when duelists found themselves mocked and laughed at by the younger generations. The idea of risking one’s life to defend one’s reputation was now disproportionate and absurd.

The rise of feminism

Industrialization has always been followed by feminism. Improved technology reduced the drudgery of raising children and running a household, allowing women to participate more in public life and build an identity distinct from that of their families. Women have always played an outsized role in pacifist, humanitarian, and temperance organizations. Women consistently support more liberal and less warlike politicians than men do.

The more dignified status of women fundamentally changed the marketplace for sexual partners. Rather than men competing with each other for dominance and taking women as non-consensual spoils, men now earned their mates by wooing women directly. Women used their new leverage to demand exclusivity from their partners, a smaller number of children with greater investment in each one, and more involvement from fathers in family life. In the age-old battle of dads versus cads, being a dad was now the more effective male reproductive strategy. Men’s testosterone levels decline when they have a steady partner and decline further when they are actively raising children. Governments, activists, and religious leaders promoted a cultural norm of responsible employment, monogamous marriage, and active fatherhood as a way of keeping men out of trouble. Many industrial-era conservatives have lamented the decline of traditional masculine culture, but this stance ignores the great harm that cad culture has historically inflicted on women and children.

The Counter-Enlightenment

The agrarian era was sometimes a subject of nostalgia for people who didn’t live through it. Some malcontents objected to the inequalities that accompanied capitalism, the cultural diversity that accompanied urbanization, the moral non-clarity that accompanied secularism, the decadence that accompanied commercialism, the feminism that accompanied liberalism, and the unrootedness that accompanied individualism. Marxism arose on the left and various flavors of hyper-nationalism arose on the right. Counter-Enlightenment ideologies rejected the Enlightenment-era focus on individual autonomy and equality in favor of an agrarian-style ethic of absolute authority and total subordination to a collective. These ideologies had core narratives similar to many old religions: an idyllic agrarian past, a fall from grace, a heroic group struggle against boundlessly evil opponents, an epic battle at the climax of history, and an eternal utopia that will come after victory. Since these ideologies viewed their planned utopias as bringing unlimited good, they had few qualms about using coercion to bring them to life. Since their views of society were collectivist, they had few qualms about purging subgroups of the population that they saw as impeding the greater good.

Though war deaths have declined in per-capita terms throughout history, World War I and World War II are the most recent reversal in this trend. Adjusted for world population size, World War I was the 16th deadliest quarrel in history and World War II was 9th. World War I was remarkable in its scale but not in its core trajectory: an honor-based standoff between countries, an enthusiastic pile-on by overconfident governments expecting a quick victory, a prolonged and costly war of attrition, and a Pyrrhic victory for the winning side. Seeking to delegitimize war as an institution, the post-WWI peace deal invoked the idea of ethnic self-determination, the notion that national borders should be determined by the distributions of ethnic groups and not by the outcomes of wars. Nazi Germany exposed the flaws of this model by making territorial demands for regions of other countries containing ethnic Germans, then mounting invasions of neighboring lands with the intent of Germanizing them. In contrast to World War I’s nationalist causes, World War II was a war of ideology, with various Counter-Enlightenment regimes seeking to expand their revolutions abroad.

To a significant degree, the atrocities of the 20th century were a case of bad luck. Much of the 20th century’s mass murder was the result of the grand ambitions and personal quirks of three men in particular: Adolf Hitler, Joseph Stalin, and Mao Zedong. The Soviet Union rapidly became less warlike and repressive after the death of Stalin, as did China after the death of Mao. Historians considering World War II’s what-if scenarios generally agree that if a Nazi leader other than Hitler had been in charge, there would likely have been no war in Europe and there almost certainly would have been no Holocaust.

The Cold War: peace between states, strife within them

In contrast to the chaos of the first half of the 20th century, the second half marked the most enduring peace between great powers in history. World War II was the last time two great powers ever fought on each other’s turf, while the Korean War was the last time their troops fought each other directly. Germany and Japan did not seek revenge for World War II, instead defying all expectations by turning into some of the most peaceful cultures in the world. Rather than become a normal part of modern warfare, nuclear weapons became globally taboo in a manner similar to chemical weapons and were never used again. The widely-anticipated third world war between the Western Bloc and the Soviet empire never came.

The decline of inter-state warfare

The post-WWII international order abandoned the principle of ethnic self-determination. Aligning borders with ethnic distributions had always been an impossible geometry problem because ethnic distributions tend to be fractal and probabilistic rather than sharp. As Hitler in particular had demonstrated, the ideal of a homogeneous ethno-state can be used to justify irredentist wars abroad and ethnic cleansing at home.

The new world order instead recognized each existing sovereign state’s right to exist and right to govern its existing territory. All borders were now frozen and any attempt to change them by force was now a taboo act of aggression. Unlike earlier taboos, this new taboo had clear red lines and gave countries a selfish stake in making sure it was upheld. When countries broke up, such as during the decolonization of Africa or the breakup of the Soviet Union, pre-existing administrative boundaries became the new national borders. The world’s flash points were usually places with a disputed post-colonial status and no historical border to fall back on, such as Israel/Palestine or Kashmir. No war since World War II between countries with a previously accepted border has ended with a non-consensual and internationally-recognized land grab. No United Nations member country has ever been wiped off the map by conquest; the closest anyone got to succeeding was Iraq’s 1990 invasion of Kuwait, which was rebuffed by an international military coalition.

In a world with often-arbitrary borders, all countries had to accept that they were multi-cultural. Governments could not pretend to be the crystallized soul of an ethnic group and instead needed to legitimize themselves to their people in other ways. Governments increasingly pivoted towards mundane but noble pursuits such as ensuring an inclusive social contract and improving the standard of living of their citizens. Since wartime destruction entails a reversal of economic progress, governments grew increasingly hesitant about launching attacks that could potentially prompt retaliation against domestic targets.

The post-WWII world was a golden age of international cooperation and inter-governmental organizations. In perhaps the most notable example, a forum meant for consolidating coal and steel policies between a few European countries evolved into what is now the European Union. Countries with greater involvement in inter-governmental organizations have been less likely to go to war, even after controlling for other variables. Inter-governmental organizations open up lines of communication between countries, place them on a cooperative footing with one another, and raise the cost of aggression due to the threat of getting excluded. Many disputes that might have led to war in the past were now resolved peacefully, with both sides making concessions to the other so that both sides can back down while saving face. The idea of democratic neighbors like the US and Canada going to war was so preposterous that it was only ever proposed as a joke. Hardly any inter-state dispute anywhere was existential enough to warrant a conventional war, let alone a nuclear one.

A culture of war-weariness

As the most thoroughly-documented and high-tech genocide in history, the Holocaust was a major turning point in humanity’s views of genocide. Genocide was not even an English word until 1944, but within just a few years, it was prohibited by international convention as a crime against humanity for which a perpetrator could be prosecuted by any country.

Even as saber-rattling between countries sometimes continued, the world as a whole underwent demilitarization. Most countries cut the per-capita size of their standing armies, shortening or abolishing conscription. Public monuments increasingly honored people other than war heroes. Depictions of war in popular media increasingly emphasized war’s tragic, brutal, and absurd aspects. The citizens of countries that were fighting wars abroad grew increasingly restless as costs and casualties mounted, especially as independent media offered alternatives to government narratives.

A smarter society

The 20th century was an era of vibrant academic research in many domains, with many of its findings becoming common knowledge or influencing the design of institutions. Psychology showed the ways in which otherwise good people can be made to commit cruel acts or to become indifferent to them. Game theory showed the ways in which groups of actors can be led astray towards ruinous outcomes that no one wanted. The study of history revealed that most present-day cultures have surprisingly shallow roots and sordid pasts, undermining a lot of nationalist mythology.

Human intelligence rose significantly during the 20th century as a result of better education, better nutrition, better healthcare, and a more symbolically-complex physical environment. IQ tests needed to be recalibrated several times to keep the population average at the pre-defined score of 100. The mental skill that improved the most was abstract reasoning, a skill that schools increasingly cultivated at the expense of rote knowledge. More intelligent people are less likely to commit violent acts, more likely to be cooperative by default, and more likely to hold classical liberal political views.

Decolonization and power vacuums

The major European colonial powers gave up their remaining colonial possessions in the decades following World War II; by this point, the colonies had become both an economic and a political liability. Colonial wars went extinct as a category of war.

As imperial powers retreated, many former colonies attempted to implement democratic government. In the West, most countries didn’t become democratic without first having become literate, liberal, urbanized, and industrialized, but the former colonies were often none of these things. These unprepared democracies instead evolved into anocracies, ineffective governments characterized by spotty rule of law, rampant corruption, and weak civic norms. Especially in countries with great oil or mineral wealth, politics was a zero-sum battle between regions and ethnic groups for monopolization of these resources.

Democracy cannot work unless a culture renounces violence as an acceptable tool of politics, but such a norm was usually not in place following colonization. In many countries, the military was a political actor in its own right, sometimes exploiting a crisis to seize power by force. In many others, factions excluded from the political process took up arms against the government, leading to civil wars where weak governments battled weak rebel groups. Civil wars were nothing new, but it was unprecedented for civil wars to make up such a large fraction of the world’s total war casualties. Most of these civil wars had a localized scope, low intensity, and hard-to-define duration, overall causing much less destruction than most inter-state wars.

The rights revolutions

By the mid-20th century, literacy and access to mass media were universal within developed countries. People were more aware of worldly injustices than ever before and more sympathetic to its victims. The humanitarian revolution entered into an acceleration phase. The 20th century’s rights revolutions reduced violence sometimes by curtailing government aggression directly and sometimes by bringing additional groups under the government’s protection. In most cases, a subset of the population already enjoyed certain rights and protections, so the movements were often a matter of extending these rights to everyone else. Public opinion on many issues completely flipped in as little as fifty years, always in a more compassionate direction.

Racial and ethnic minority rights: Minority groups often suffered from severe disparities in policing, with governments prosecuting minority-on-majority crime relentlessly while turning a blind eye to majority-on-minority or minority-on-minority crime. The term “race riot” today conjures up images of violent protests by minorities, but historically it meant the opposite: frenzied mobs of people from the majority ethnic group going on rampages against minorities that featured beating, looting, property destruction, and rape. Rather than the small-scale acts they tend to be today, racial lynchings were once public and widely-attended events with a carnival-like atmosphere. Unpunished violence against minorities declined for several reasons: the majority group’s empathy increased, the minority group got more involved in governance and policing, mob violence got increasingly scorned as a political tactic, and national governments got in the habit of calling in national militias during crises where the local police was known to be biased.

Women’s rights: Rape and intimate partner abuse started being taken seriously and actively prosecuted. As divorces became easier to obtain, spousal homicide rates declined significantly. Especially as mixed-gender workplaces became the norm, aggressive macho behavior from men became increasingly ridiculed and demonized.

Children’s rights: Whereas agrarian cultures tended to view children as little rascals who needed to be socialized by force, industrial cultures cherished children as intrinsically innocent. Contraception significantly reduced unwanted pregnancies and abortion offered a more ethically palatable alternative to infanticide; infanticide rates fell a thousandfold in the 20th century West and it was finally criminalized. Scientific evidence showed that adult-style moralizing, threatening, and punishing is ineffective and counterproductive when dealing with children. Corporal punishment fell into decline both in schools and at home, getting banned outright in a growing number of jurisdictions. Governments began taking child abuse seriously. Beginning in the 2000s, schools started actively cracking down on bullying between children.

Gay rights: Homosexuality, especially among men, was widely demonized by agrarian societies, an example of the human tendency to attach moral meaning to things that gross them out. The first priority of the gay rights movement was decriminalization; this was followed by drives for anti-discrimination protections, cultural destigmatization, and legal recognition of same-sex relationships. The public’s sympathy towards homosexuals increased, especially as the scientific evidence mounted that a homosexual orientation is not freely chosen and is not correlated with any pathologies. Knowing openly gay people in one’s own life was strongly correlated with acceptance of gay people in general. Even the people who viewed homosexuality as immoral increasingly adopted the stance that it is not the government’s job to enforce this moral claim.

Animal rights: The once-common belief that animals were unfeeling automatons was thoroughly discredited by the 20th century. New laws prohibited the mistreatment of animals in agriculture, research, and the entertainment business. Animal blood sports such as cockfighting were banned. Recreational hunting and fishing fell into decline and became increasingly associated with old men. Younger generations of Westerners began eating less meat than their parents’ generation. Vegetarianism became a socially tolerated and accommodated stance, albeit a rare one that most people lapsed out of. The animal rights movement was notable in that animals were not advocating for themselves and people had nothing to gain from reducing animal suffering; the movement happened because treating humans well while treating animals badly had become too big of a moral contradiction. Humanity’s circle of sympathy had expanded to its maximum possible size, covering any conscious being capable of suffering.

The various rights revolutions always proceeded in tandem because each one used analogous reasoning to the others. Most of the rights revolutions occurred first in Western Europe and Anglosphere countries, followed by blue US states, followed by red US states, followed by the democracies of East Asia and Latin America, followed by authoritarian countries, followed by sub-Saharan Africa and the Islamic world at the end. The liberalization of the world was uneven, but no part of the world was untouched by the rights revolutions.

The failure of violent activism

Though this was largely forgotten after 9/11, the late 20th century was a golden age of terrorism. The new mass media allowed terrorists to achieve widespread notoriety on a small budget. Most terrorist groups were religious, secessionist, or Marxist in their ideology. Terrorism is good at attracting attention to itself, but overall it has never been more than a tiny fraction of overall violence. No terrorist group anywhere in the world achieved its stated political goals and very few groups survived longer than a decade. Terrorists were consistently a political liability for their movements and often accomplished nothing besides uniting both the government and the public against them.

In contrast, many of the most successful activist movements of the 20th century were staunchly peaceful. A pre-commitment to peaceful protesting prevents a movement from being hijacked by hotheads, it allows the movement to claim the moral high ground, and it sows strategic divisions among the movement’s opponents. Compared to earlier political struggles against absolute monarchy, colonialism, and totalitarianism, the struggle against bigotry and indifference was a much more peaceful one with remarkably few martyrs. In many cases, the rights revolutions faced little opposition and required little persuasion; public opinion had already changed and the law was simply catching up.

The Baby Boomer counterculture

The civilizing process has sometimes gone into temporary reversal throughout the course of human history. Among Western countries, the most recent regression spanned from the 1960s to the 1980s, with crime rates tripling from 1950s levels.

The counterculture was driven primarily by the large Baby Boomer generation. Large youthful cohorts were nothing new, but the Baby Boomers lived in a world with universal mass media and felt the strength of their numbers. Baby Boomers tribalistically identified with their generational cohort to a greater extent than any generation before or since. As a result, they were able to pull off the most successful youth cultural rebellion in history.

The counterculture favored experimentation over tradition, spontaneity over discipline, and indulgence over self-restraint. The cultural script of employment, marriage, and family that had tamed the past few generations was now seen as selling out. Rather than picking up the manners of the upper classes, the middle class instead picked up uncouth behaviors from the lower classes.

The establishment suffered a crisis of credibility with the young Baby Boomers due to slowness in responding to the rights revolutions, unpopular foreign wars like Vietnam, colonial-era atrocities that were just coming to light, and a new concern for despoliation of the environment. Governments internalized some of these complaints and became less assertive, leading to a retreat in the rule of law. With the police providing less protection, crime and social disorder increased along all dimensions. Street gangs and cultures of honor saw a resurgence. Well-off people fled to suburbs and gated communities, leaving behind impoverished and crime-ridden urban cores.

The New Peace

The end of the Cold War was widely recognized as a pivotal moment in world history even as it was occurring. Breaking with the usual historical trend, the Soviet Union did not violently resist when its outer possessions declared independence. Many communist regimes fell without major bloodshed, with some of the wealthier and better-educated countries successfully turning into democracies.

Truth and reconciliation

Following the collapse of the Soviet Union, many Marxist-leaning governments and rebel groups in the developing world lost their Soviet support. The West likewise stopped giving material support to their opponents, leaving both sides too weak to fight.

Civil wars around the world finally started ending at a faster rate than they were starting. Most civil wars ended in peace agreements rather than with a wipeout on the battlefield. The most successful peace agreements tended to be the ones that accepted a flawed justice and turned a new page, avoiding a detailed settling of scores.

Starting in the 1980s, governments began making official apologies for historical atrocities. The most high-profile apologies were Germany’s apology for the Holocaust and the United States’ apology for the internment of Japanese-Americans during World War II.

In places where conflicts continued, organizations like the United Nations were highly successful at reducing bloodshed using international peacekeepers. Even a small and lightly-armed peacekeeping force could bring the benefits of a Leviathan and break warring parties out of a Hobbesian Trap. By telling both sides of a conflict that they are monitoring the other side for compliance with ceasefires or other agreements, peacekeepers could put both sides of a conflict at ease. An army that is not afraid of a surprise pre-emptive strike is less likely to feel compelled to try one themselves.

The 1990s crime decline

Crime rates in the Western world rapidly declined during the 1990s back down to 1950s levels and have remained there ever since. Some Western cities went from rotten to squeaky-clean in as little as a decade, most famously New York.

Part of the shift was demographics; the youngest Baby Boomers were entering their 30s and their most crime-prone years were now behind them. A bigger contributor to the decline was a political backlash against lawlessness and a re-assertion of the rule of law. The police and courts made many innovations during this period, often drawing on improved knowledge of human psychology. Knowing that punishments don’t deter short-sighted criminals, governments focused on increasing the likelihood of getting caught. Knowing that people are very sensitive to environmental cues, governments worked on giving cities a clean and orderly appearance, making the police a visible day-to-day presence, and prioritizing high-visibility crimes. Knowing that a small fraction of the population commits most of its crimes, governments got better at keeping a close eye on known troublemakers using officials like probation and parole officers. Knowing that people treat in-groups and out-groups differently, governments tried proactively building cooperative relationships with local neighborhoods to build trust in the police. Knowing that people see erratic authority figures as thugs rather than as upholders of group norms, governments got better at making the criminal justice system feel professional and predictable.

In many respects, popular culture looked like it was undergoing degeneration. Movies and TV shows were becoming more violent, internet pornography became easily accessible, violent video games arose as a new form of media, men were cursing more in public, and women were showing more skin. However, violence in real life did not rebound, and neither did other social pathologies like property crime, drug abuse, or teen pregnancy. Unlike the Baby Boomers, Generation X and later cohorts showed an ability to separate mass media from real life. Younger cohorts were able to dabble in many subcultures, including seedy ones, without becoming fully consumed by any of them. The new bohemians differed from the old ones in that they privately lived law-abiding lives with a healthy amount of self-control. After a false start in the 20th century, Western countries in the 21st century figured out the art of becoming informal without becoming uncivilized.

Islamism

Following the fall of communism, Islamism overtook Marxism as the world’s most visible counter-Enlightenment ideology. The War on Terror in the 21st century prompted a fresh look into the Islamic world’s status as a violent region and a social laggard.

During the Middle Ages, the Islamic world was the world’s most peaceful and progressive region, whereas Christian Europe was consumed by superstition and sectarian wars. Europe’s turning point was the invention of the printing press, which spread across Europe but not to the neighboring Ottoman Empire. While Europe underwent humanitarian and liberal revolutions, the Islamic world stayed the same, creating a gap in social values that remains visible today. There are currently no liberal democracies in the Muslim world, though this is not unique to the region; no liberal democracy has ever yet taken root in any country with low educational attainment. The Muslim world currently faces the same exogenous forces that have historically liberalized other parts of the world, including greater rule of law, education, commerce, and cosmopolitanism.

Though most Muslims vaguely want society to run on Islamic principles, the puritanical utopian vision of Islamist groups is usually too extreme for them. Islamist groups have tarnished their domestic reputations by brutalizing innocent and sympathetic victims, repeating the mistakes of other terrorist groups throughout history. Al-Qaeda-style groups have been unable to topple and replace any of the Muslim world’s old regimes.

The war on Islamism did not feature the dehumanization and tribalist zeal typical of past wars. The 9/11 attacks and the Madrid train bombings were the sorts of events that would have prompted large-scale anti-Muslim pogroms had they happened in an earlier generation, but the West’s domestic response was muted and restrained. This time around, Westerners made a distinction between the attackers and their Muslim neighbors, mostly rejecting conspiratorial or guilt-by-association rhetoric about the latter. The wars in Iraq and Afghanistan became a major political liability for the US government after just a few thousand soldier deaths, a whole order of magnitude lower than Vietnam. Westerners were outraged by civilian deaths among foreign populations and even more outraged by reports of clandestine torture operations. On the other side, the Muslim world’s anger towards the West was mostly directed at interventionist great powers like the United States, Britain, and France, not towards Christendom as a whole.

A culture of political correctness

For the first time in history, violent crime is mostly limited to poor people and war is mostly limited to poor countries. Violence is no longer a part of mainstream polite society and has been pushed to the margins.

The civilizing process has always left behind new standards of behavior and new taboos. The rights revolutions were no different, creating a class of inoffensive “politically correct” political stances. Political correctness disallows rhetoric that is demonizing, dehumanizing, essentialist, exclusionary, or eliminationist.

Political correctness is not internally consistent. PC culture is staunchly nurture-over-nature on some questions, such as on gender-based or race-based differences, while staunchly nature-over-nurture on others, such as homosexuality. PC culture holds that people are intrinsically good before society corrupts them, yet it attacks its opponents with a zeal that suggests they view them as evil rather than merely misguided. PC culture holds that nobody is irredeemable or inferior, a platitude that nobody follows in their private life. It should be noted, however, that no set of taboos throughout history has ever been wholly rational or internally consistent. Political correctness is absolutely a fair price to pay for the modern world’s record-low rates of out-group aggression.

In some contexts, the taboo on violence has reached the point of diminishing or negative returns. Society’s efforts to completely eradicate crimes like terrorism and child abduction have brought more costs than benefits. Incarceration rates in some Western countries are excessive, most notably in the United States. Strict protections of test subjects in research prevent a lot of potentially constructive science from getting done. A preoccupation with protecting children from all possible dangers and bad influences has made parenting extremely demanding and stressful. As non-violence becomes an increasingly entrenched norm, society may one day be ready to thoughtfully revisit such questions.

It is common for modern people to complain that the modern world is violent and getting worse. However, such a statement usually implies that the speaker sees violence as a social pathology caused by human failure rather than as something inevitable like the weather. This shift in mindset is only a few centuries old. The future is uncertain, but it is difficult to imagine human sacrifice, torture-executions, blood sports, divinely commanded genocides, wars triggered by personal insults, absolute monarchy, witch hunts, religious inquisitions, the death penalty for petty theft or unpopular speech, chattel slavery, dueling, or totalitarian communism making a big comeback anytime soon.