The demographic history of the Jews in the Middle Ages may be characterized by two main phenomena: i) a sharp drop in the number of Jews until the beginning of the modern period, due mainly to conversions; and, ii) early urbanization. Until now, these features have been analyzed as primarily...

This paper distills and extends recent research on the economics of human development and social mobility. It summarizes the evidence from diverse literatures on the importance of early life conditions in shaping multiple life skills and the evidence on critical and sensitive investment periods...