Many believe that these grand institutions, the bequests of Western civilization, represent the products of reason and the rise of rationality. These institutions—the rationalists argue—are what you get once you strip away Church dogma and apply “reason.” This is true even of Protestantism: many believed, and some continue to hold, that (some version of) Protestantism is what you get if you apply reason to the truths expressed in by cultural evolution during the Middle Ages—by the demolition of Europe’s kin-based institutions (Chapters 5–8), the expansion of impersonal markets (Chapter 9), the rise of domesticated forms of intergroup competition (Chapter 10), and the growth of a broad, mobile division of labor in urban centers (Chapter 11). The WEIRDer psychology that was emerging in fragmented communities across Europe, along with the accompanying changes in social norms, made people in these populations more likely to devise, endorse, and adopt particular kinds of ideas, laws, rules, policies, beliefs, practices, and arguments. Many modern ideas about law, government, science, philosophy, art, and religion that would have been “unthinkable,” aversive, or nonintuitive to people in most complex societies over most of human history began to “fit” the emerging proto- WEIRD psychology in medieval and Early Modern Europe. In many cases, these new ideas, laws, and policies were filtered and selected by relentless intergroup competition between voluntary associations, including among cities, guilds, universities, monasteries, scientific associations, and eventually territorial states.

Joseph Patrick Henrich, The WEIRDest people in the world: How the west became psychologically peculiar and particularly prosperous, New York, 2020, p. 395