Rationalist approaches to economics assume that people value their own interests over the interests of strangers. Cohn et al. wanted to examine the trade-off between material self-interest and more altruistic behaviors (see the Perspective by Shalvi). They distributed more than 17,000 wallets containing various sums of money in 355 cities across 40 countries. In contrast to what rationalist theories of economics predict, citizens were more likely to return wallets that contained more money. The findings also reveal a high level of civic honesty across nations.

Science , this issue p. [70][1]; see also p. [29][2]

Civic honesty is essential to social capital and economic development but is often in conflict with material self-interest. We examine the trade-off between honesty and self-interest using field experiments in 355 cities spanning 40 countries around the globe. In these experiments, we turned in more than 17,000 lost wallets containing varying amounts of money at public and private institutions and measured…