Joseph Henrich’s The WEIRDest People in the World: How the West Became Psychologically Peculiar and Particularly Prosperous is an enormous, ambitious attempt to explain something that social scientists have often taken for granted: people in modern Western societies are psychologically unusual.
WEIRD stands for Western, Educated, Industrialized, Rich and Democratic. Henrich, an anthropologist and evolutionary biologist, argues that WEIRD people differ measurably from much of humanity in the ways they think, reason, cooperate, marry, trust strangers and understand themselves. We tend to be more individualistic, analytical and impersonal. We are unusually willing to cooperate with strangers and join organizations composed of people to whom we are not related. We put considerable faith in abstract principles, rules and institutions.
Henrich argues that these differences are not merely superficial cultural habits. Culture changes people. Literacy, education, occupations and social organization can alter cognition and even aspects of brain development and physiology. Human beings are products of biological evolution, but we are also products of cultural evolution, and the two processes interact.
The book immediately reminded me of Ian Morris’s Why the West Rules—For Now and Niall Ferguson’s Civilization. Both attempt to explain the extraordinary rise of Western societies. Jared Diamond and Yuval Noah Harari have approached related questions on an even larger historical scale. Henrich’s answer, however, surprised me because the institution at the center of his explanation is one that I had never encountered in those other accounts: the medieval Catholic Church.
More precisely, Henrich emphasizes what he calls the Church’s Marriage and Family Program.
Beginning in late antiquity and accelerating through the Middle Ages, the Western Church progressively prohibited practices that had bound people into large kinship networks. Most important was its increasingly aggressive prohibition of marriage between relatives, including cousins and eventually even surprisingly distant relatives. The Church also discouraged polygyny, arranged marriages, adoption and other practices that strengthened clans and extended families.
None of this was intended to create modern Western civilization.
Yet Henrich argues that the unintended consequences were revolutionary.
For most of human history, kinship was among the most important organizing principles of society. People depended upon extended families and clans for protection, marriage, economic opportunity and social identity. Trust was concentrated among relatives. Property and inheritance reinforced family networks. Marriage created alliances between kin groups.
The Church gradually weakened that system in Western Europe.
As cousin marriage declined, extended kin networks fragmented. Households became smaller and increasingly centered on the nuclear family. People became more geographically and socially mobile. A person could no longer depend exclusively upon cousins, uncles, brothers and clan members. Increasingly, individuals had to form relationships with unrelated people.
Out of that transformation came one of Henrich’s most important insights: when kinship weakened, voluntary associations grew.
Guilds, monasteries, universities, religious orders, chartered towns, professional organizations and eventually commercial corporations brought unrelated people together around shared purposes. Cooperation increasingly depended not upon blood but upon rules, contracts, reputation and trust.
This is where Henrich’s psychological argument becomes particularly powerful. Institutions did not simply change because Western people thought differently. Western people came to think differently because they spent generations living within different institutions.
The causal arrow runs both ways.
People accustomed to dealing with strangers become more comfortable trusting strangers. People living under impersonal rules become more inclined to apply universal standards. People freed from dense kinship obligations become more individualistic. They increasingly understand themselves through personal characteristics, occupations, beliefs and accomplishments rather than primarily through family relationships.
Over centuries, Henrich argues, these changes helped produce the extraordinarily peculiar psychology we now call WEIRD.
The consequences multiplied.
Greater individualism encouraged geographic mobility. Impersonal trust facilitated commerce. Voluntary organizations allowed people to cooperate on increasingly large scales. Universities brought scholars together outside kinship structures. Guilds organized craftsmen. Trading companies joined investors who might not even know one another personally.
Eventually the same psychological tendencies contributed to political and intellectual transformations.
The Reformation intensified individual engagement with scripture and literacy. Protestantism encouraged reading, schooling and personal religious responsibility. The Enlightenment pushed universal principles and individual reason still further. Modern science, representative government and market economies flourished within societies increasingly organized around individuals and impersonal institutions rather than clans.
Henrich is careful not to claim that the Catholic Church planned any of this. That is precisely what makes his argument so fascinating.
The Church did not prohibit cousin marriage in order to create capitalism, universities, liberal democracy or the scientific revolution. Medieval bishops were not designing the Enlightenment. Cultural evolution produces enormous unintended consequences. A set of religious rules concerning marriage and family gradually changed social organization; social organization changed psychology; psychological changes encouraged new institutions; and those institutions further changed the people living within them.
It is an extraordinary feedback loop.
Henrich also undermines a mistake that Western researchers have repeatedly made. Psychology has often studied American and European university students and then treated the resulting conclusions as statements about universal human nature. But if Henrich is correct, these research subjects belong to one of the most psychologically unusual populations on Earth. What psychologists thought was simply “human” behavior was sometimes WEIRD behavior.
That alone makes this an important book.
But reading The WEIRDest People in the World also made me think repeatedly about the fragility of the institutions Henrich describes.
One of the great achievements of WEIRD societies has been the development of institutions intended to operate independently of family and clan. Universities, courts, corporations, civil services and democratic governments work best when positions are filled according to competence and rules rather than kinship or personal loyalty. The ideal is imperfectly realized, of course, but the principle itself represents a remarkable historical departure.
That makes the current erosion of institutional norms in the United States particularly disturbing to me. The current President promotes family members, personal loyalists and toadies. Those selected previously for independence or competence have been dismissed. Viewed through Henrich’s argument, it resembles a retreat from one of the distinctive achievements of the long cultural evolution he describes: the replacement of kinship and personal allegiance by impersonal institutions. Henrich talks about the different trajectory and wealth of Northern Italy and Sicily. The former is WEIRD and successful. The later is poor and dominated by gangsters. Trump is dragging the US into mobster government.
History is full of rulers who trusted relatives and loyal dependents precisely because independent institutions threatened their power. Liberal societies attempted something much harder: institutions whose legitimacy did not depend upon personal loyalty to the ruler.
Henrich therefore left me with an unexpected appreciation for how historically unusual—and potentially fragile—our civilization is.
Morris explains much about geography and social development. Ferguson identifies institutions that helped Western civilization achieve extraordinary global power. Diamond emphasizes geography, domesticable plants and animals, disease and technology. Henrich goes somewhere different. He asks what centuries of institutional change actually did to the people themselves.
The West did not simply acquire different technologies and institutions. Over many centuries, Western societies produced people psychologically adapted to a world of strangers, voluntary associations, impersonal rules and individual choice. Those people then created institutions that reinforced those characteristics in succeeding generations.
The process was neither planned nor inevitable.
That may be the most important lesson of The WEIRDest People in the World. What cultural evolution created, cultural evolution can presumably change again.
After finishing this remarkable book, I found myself looking differently at institutions I had previously taken for granted. Universities, professional organizations, independent courts, corporations and representative governments are not simply fixtures of modern life. They are products of an extraordinarily long and improbable historical development.
Henrich has written a book about why Western people became WEIRD.
He also, perhaps unintentionally, reminds us how much work it took to become that way—and how unwise it would be to assume that we must remain so.
