Joseph Henrich
Your mind is not a universal human baseline, but a historically unusual profile shaped in part by medieval Catholic marriage rules that weakened ancient family clans and gradually altered Western psychology.
People from WEIRD cultures possess a peculiar psychology characterized by intense individualism, a focus on personal intentions over social context, and a reliance on internal guilt rather than external shame.
The Catholic Church helped trigger this psychological transformation by enforcing strict marriage prohibitions that weakened the dense, kinship-based clans that dominated human history.
As extended families became less central, Westerners increasingly formed voluntary associations like guilds, universities, and charter towns that operated on more impartial rules rather than blood ties.