The origins of collectivistic and normative psychological variation: Testing the rice theory of culture in Japan

• The current study finds no evidence that regional variation in self-reported metrics associated with a collectivistic psychology or with normative tightness are tied to variation in historical rice farming in Japan. • The study also finds little evidence that prefectural variation in collectivistic behaviours are tied to variation in historical rice practices. • The study analyzes whether the duration of time paddy rice has been farmed predicts contemporary psychology, which has been hitherto untested. The rice theory of culture posits that cultures that have traditionally subsisted on paddy rice have become more collectivistic than those that have traditionally farmed other crops or survived on other modes of subsistence. Using up to 4,185 self-report responses from the 2006 Japanese General Social Survey, we analyzed whether historical variation in rice farming predicts modern-day psychological variation in Japan. Several surveyed attitudes were selected based on their relation to psychological traits known to vary between individualists and collectivists, as well as between normatively tight and loose cultures. We tested whether (i) the extent to which a prefecture has traditionally farmed rice and (ii) the duration of time for which rice has been farmed in a prefecture predict how collectivistic or normative its modern-day residents are. Overall, we find no evidence that regional variation in self-reported collectivism and normative tightness are tied to variation in past rice farming. We also find little support for an association between historical rice farming practices and two behaviours — blood donations and patent registrations — used to assess collectivism–individualism in other contexts. Rice farming across Japan. Shading shows the percentage of paddy rice farming at the prefectural level, based on governmental data from 1965 for 46 of the 47 prefectures (grey lines). Dates (in years before present) show the estimated introduction of paddy rice farming across eight areas (black lines), which correspond to 45 prefectures. Percentage data from the Ministry of Agriculture, Forestry and Fisheries (1965/2023) , dates from model B in Crema et al. (2022) . Note that Okinawa prefecture is not shown as both data are unavailable.