Researchers dropped 17,000 wallets in 355 cities across 40 countries. Wallets with 94 USD equivalent cash returned most often worldwide. Empty wallets returned least frequently. Higher cash makes theft psychologically costlier, preserving self-image as honest. Result upends economic models predicting more dishonesty with bigger gains. Poles ranked top 10 honest alongside Swiss, Norwegians, Dutch, Danes, Swedes, Czechs, New Zealanders, Germans, French. Chinese ranked lowest in honesty. Key in wallet boosted returns more than fixed cash amount. Altruism toward owner weaker than self-image maintenance. Most people prioritize honest self-view over short-term gain.