The Weirdest People in the World

While religious convictions appear central to the early spread of literacy and schooling, material self-interest and economic opportunities do not. Luther and other Reformation leaders were not especially interested in literacy and schooling for their own sake, or for the eventual economic and political benefits these would foster centuries later. Sola scriptura was primarily justified because it paved the road to eternal salvation. What could be more important? Similarly, the farming families who dominated the population were not investing in this skill to improve their economic prospects or job opportunities. Instead, Protestants believed that people had to become literate so that they could read the Bible for themselves, improve their moral character, and build a stronger relationship with God. Centuries later, as the Industrial Revolution rumbled into Germany and surrounding regions, the reservoir of literate farmers and local schools created by Protestantism furnished an educated and ready workforce that propelled rapid economic development and helped fuel the second Industrial Revolution.

When the Reformation reached Scotland in 1560, it was founded on the central principle of a free public education for the poor. The world’s first local school tax was established there in 1633 and strengthened in 1646. This early experiment in universal education soon produced a stunning array of intellectual luminaries, from David Hume to Adam Smith, and probably midwifed the Scottish Enlightenment. The intellectual dominance of this tiny region in the 18th century inspired Voltaire to write, “We look to Scotland for all our ideas of civilization.”

Let’s follow the causal chain I’ve been linking together: the spread of a religious belief that every individual should read the Bible for themselves led to the diffusion of widespread literacy among both men and women, first in Europe and later across the globe. Broad-based literacy changed people’s brains and altered their cognitive abilities in domains related to memory, visual processing, facial recognition, numerical exactness, and problem-solving. It probably also indirectly altered family sizes, child health, and cognitive development, as mothers became increasingly literate and formally educated. These psychological and social changes may have fostered speedier innovation, new institutions, and—in the long run—greater economic prosperity.

You can’t separate “culture” from “psychology” or “psychology” from “biology,” because culture physically rewires our brains and thereby shapes how we think.

Non-WEIRD populations might, for example, “lose face” in front of the judging eyes of others when their daughter elopes with someone outside their social network. Meanwhile, WEIRD people might feel guilty for taking a nap instead of hitting the gym even though this isn’t an obligation and no one will know. Guilt depends on one’s own standards and self-evaluation, while shame depends on societal standards and public judgment.

I learned, among other things, that an oxen team can reliably pull your four-wheel-drive Subaru out of deep mud, and that it’s possible to outrun a pack of guard dogs because they wear out before you do, as long as you’re prepared to do seven-minute miles for several miles.

Tapping our mentalizing abilities, synchrony also harnesses the fact that we humans unconsciously track who is mimicking us and use it as a cue that they like us and want to engage with us. This arises in part because mimicry is one of the tools we use to help us infer other people’s thoughts and emotions—if someone frowns, you automatically micro-frown to better intuit their feelings. During synchronous dances, drills, or marches, our mental tracking system is flooded with false mimicry cues, suggesting that everyone likes us and wants to interact. Since we’re usually positively inclined to such affiliative cues, and the synchronous patterns cause all participants to feel similarly, a virtuous feedback loop can emerge.

Research with both children and adults confirms that working together on a shared goal deepens group solidarity and strengthens interpersonal connections.

Though kinship does assert itself from time to time, such as when U.S. presidents appoint their children or in-laws to key White House posts, it usually remains subordinate to higher-level political, social, and economic institutions.

in 786, a papal commission again arrived in England, this time to assess the progress on Christianizing the Anglo-Saxons. Their report indicates that, although many had been baptized, there were serious issues among the faithful surrounding (1) incest (i.e., cousin marriage) and (2) polygyny. To uproot these stubborn customs, the Church promulgated the notion of “illegitimate children,” which stripped the inheritance rights from all children except those born within legal—i.e., Christian—marriages. Prior to this, as in many societies, the children of secondary wives in polygynous unions had possessed some inheritance rights. For royalty, the sons of secondary wives could be “raised up” to succeed their father as king, especially if the king’s primary wife was childless. Fighting this, by promoting the notion of “illegitimacy” and endowing itself with the power to determine who is legitimately married, the Church had seized a powerful lever of influence. These interventions made it substantially less appealing for cousins to marry or for women to become secondary wives.

The Church gradually extended its marriage prohibitions—the circle of incest—from primary relatives (e.g., daughters) and key in-laws (e.g., son’s wife) to include first cousins, siblings-in-law, and godchildren. The process first accelerated in the sixth century, under the Merovingian (Frankish) kings. From 511 to 627 CE, 13 of 17 Church councils addressed the problem of “incestuous” marriage. By the beginning of the 11th century, the Church’s incest taboos had swollen to include even sixth cousins, which covered not only blood relatives but also affines and spiritual kin. For all practical purposes, these taboos excluded everyone you (or anyone else) believed that you were related to by blood, marriage, or spiritual kinship (god relatives). However, probably because these broad-ranging taboos were used to make bogus accusations of “incest” against political opponents, the Fourth Lateran Council in 1215 narrowed the circle of incest to encompass only third cousins and closer, including the corresponding affinal and spiritual relations. Third cousins share a great-great-grandparent.

In the 11th century, for example, when the Duke of Normandy married a distant cousin from Flanders, the pope promptly excommunicated them both. To get their excommunications lifted, or risk anathema, each constructed a beautiful abbey for the Church. The pope’s power is impressive here, since this duke was no delicate flower; he would later become William the Conqueror (of England).

The Church’s footprints can be seen even more directly in modern European languages, such as English. What do you call your brother’s wife? She’s your “sister-in-law.” What’s with the “in-law” bit? Why is she like a sister, and what law are we talking about? The “in-law” bit means “in canon law,” so from the Church’s point of view, she’s like your sister—no sex or marriage, but treat her sweetly.

By 900 CE, the Church owned about a third of the cultivated land in western Europe, including in Germany (35 percent) and France (44 percent). By the Protestant Reformation in the 16th century, the Church owned half of Germany, and between one-quarter and one-third of England.51

By roughly 1000 CE, manorial censuses confirm that peasant farming families lived in small, monogamous nuclear households and had two to four children.

Beginning with Cluny Abbey (910 CE) and accelerating with the emergence of the Cistercian Order (1098 CE), monasteries became less like clan businesses and more like NGOs, with the democratic election of abbots, written charters, and a hierarchical franchise structure that began to balance local independence with centralized authority.

National populations that collectively experienced longer durations under the Western Church tend to be (A) less tightly bound by norms, (B) less conformist, (C) less enamored with tradition, (D) more individualistic, (E) less distrustful of strangers, (F) stronger on universalistic morality, (G) more cooperative in new groups with strangers, (H) more responsive to third-party punishment (greater contributions in the PGG with punishment), (I) more inclined to voluntarily donate blood, (J) more impersonally honest (toward faceless institutions), (K) less inclined to accumulate parking tickets under diplomatic immunity, and (L) more analytically minded.

So, the question is whether monogamous marriage is more like contract law, which provides a foundation for commercial markets, or more like donning neckties, a ridiculous sartorial custom that spread globally by piggybacking on European prestige. Below, I’ll make the case that monogamous marriage norms—which push upstream against our polygynous biases and the strong preferences of elite men—create a range of social and psychological effects that give the societies that possess them a big edge in competition against other groups. Let’s see how this works.

Monogamous marriage changes men psychologically, even hormonally, and has downstream effects on societies. Although this form of marriage is neither “natural” nor “normal” for human societies—and runs directly counter to the strong inclinations of high-status or elite men—

coffee shops are like monasteries; they play an unexpectedly influential role in the emergence of the modern world).

In the United States, the founding fathers largely despised political parties and consequently made no provision for them in the U.S. Constitution.

One ingenious data source for studying people’s changing work habits comes from the Old Bailey, London’s Central Criminal Court, which provides a written record of cases from 1748 to 1803. During their court testimony, eyewitnesses often reported what they were doing at the time of a crime. These “spot-checks” provide over 2,000 instantaneous observations that together paint a picture of how Londoners spent their day. The data suggest that the workweek lengthened by 40 percent over the second half of the 18th century. This occurred as people stretched their working time by about 30 minutes per day, stopped taking “Saint Mondays” off (working every day except Sunday), and started working on some of the 46 holy days found on the annual calendar. The upshot was that by the start of the 19th century, people were working about 1,000 hours more per year, or about an extra 19 hours per week.

The most prominent approach argues that humans have five largely independent dimensions of personality: (1) openness to experience (“adventurousness”), (2) conscientiousness (“self-discipline”), (3) extraversion (vs. introversion), (4) agreeableness (“cooperativeness” or “compassion”), and (5) neuroticism (“emotional instability”). These have often been interpreted as capturing the innate structure of human personality. Psychologists call these personality dimensions the “BIG-5,” but I’ll call them the WEIRD-5.40

If Charles V had executed Luther immediately at the Diet of Worms in 1521 (snuffing out the Protestant Reformation), something like Protestantism would have soon sprung up to take its place. I can suggest this with some confidence because, even prior to Luther, Protestant-like movements were already popping up. For example, a movement called the Brethren of the Common Life had diffused throughout many cities and towns in the Netherlands and into Germany during the 14th century.

Early in the Middle Ages, agricultural production was gradually improved by the water mill (sixth century, Roman origin), heavy plow (seventh century, Slavic origin), crop rotation (eighth century), and both the horseshoe and the harness (ninth century, probably from China). Water mills were deployed to mechanize the production of beer (861, northwest France), hemp (990, southeast France), cloth (962, northern Italy; Switzerland), iron (probably 1025, southern Germany), oil (1100, southeast France), mustard (1250, southeast France), poppies (1251, northwest France), paper (1276, northern Italy), and steel (1384, Belgium).

On the eve of the first millennium, rural folk began flowing into urban centers in several regions of Europe, especially in a band running from northern Italy through Switzerland and Germany into the Low Countries and eventually to London. City incorporations proliferated, and the number of people living in cities of over 10,000 rose 20-fold, from about 700,000 in 800 CE to nearly 16 million people in 1800. During the same millennium, the urban population in the Islamic world didn’t even double and China’s remained flat.

For instance, by the 12th century Europeans had developed the spinning wheel for making woolen clothing. This invention, which represents the first known application of belt-driven power, doubled or even tripled the productivity of wool spinners. Later, under the guilds, weaving efficiency increased by 300 percent between about 1300 and 1600 in the high-quality woolen industry. In the manufacture of gilded books, productivity increased by 750 percent during the 16th century.

Crucially, however, the social and psychological changes wrought by the Church’s MFP also led Europeans to absorb ideas, practices, and products from around the world more rapidly than societies that were more respectful of ancestors, devoted to tradition, and inclined to conform. Important ideas and know-how related to gunpowder, windmills, papermaking, printing presses, shipbuilding, and navigation were acquired often via circuitous routes, from prosperous societies in China, India, and the Islamic world. During the High Middle Ages, for example, returning crusaders probably brought the idea of wind power back with them from the Middle East. But, when Europeans developed this idea, their mills were mounted horizontally, which is more efficient, instead of vertically, as in Persia.

Europeans of the early modern period no doubt thought that they were superior to these other peoples, but this didn’t stop them from readily assimilating the useful ideas, crops, technologies, and practices they encountered. In many cases, the products or technologies that poured into Europe’s collective brain were rapidly modified and recombined to create new innovations.

Analyses suggest that the potato alone accelerated the growth of European cities by at least 25 percent between 1700 and 1900. Importantly, these new crops not only improved the quantity and quality of food overall, they also helped eliminate famines in Europe.

In Britain, this began in earnest under Queen Elizabeth, with the Old Poor Law of 1601. This early system, which endured until 1834, charged each parish with the obligation to care for the poor and the legal right to fund this effort through local taxes. At any given time, 5–15 percent of Britons were supported directly by the Old Poor Law. Such broader and stronger safety nets would have sharpened the population’s cognitive and social skills on average. These psychological effects, along with the greater independence from families and churches that such insurance gives individuals, help explain why stronger safety nets promote more innovation, both in preindustrial England and in the modern world.

Diamond’s biogeographic approach, however, doesn’t help us account for why the Industrial Revolution began in England, or why the Scottish Enlightenment first began to glow in Edinburgh and Glasgow. Only by considering the social and psychological changes induced by the Church’s reorganization of the family can we understand Europe’s peculiar pathway and the resulting patterns of global inequality that have developed in the last few centuries.5