Acknowledgments: We thank Francesco Giavazzi, Paola Giuliano, Eliana La Ferrara, Giuliano Milani, Guido Tabellini, Nicola Gennaioli, two anonymous referees, and participants in seminars at Brown University, the University of Chicago, New York University, European University Institute, Stockholm University, the New Economic School, and the NBER for very helpful comments. We are most grateful to Giuliano Milani for his advice and help in obtaining data and references on medieval history. We thank the Invalsi Institute for providing us with city‐level data on cheating in school. Lorenzo Ciari, Marcello Sartarelli, Luca Riva, and Riccardo Marchingiglio have provided excellent research assistance, and Peggy Eppink and Janice Luce have provided invaluable editorial help. Luigi Guiso thanks the European University Institute, Paola Sapienza thanks the Zell Center, and Luigi Zingales thanks the Center for Research in Security Prices (CRSP), the Stigler Center, and the Initiative on Global Markets at the University of Chicago for financial support. Guiso is a Research Fellow at CEPR. Sapienza and Zingales are Research Fellows at NBER and CEPR.