Tolerance, Religious Competition and the Rise and Fall of Muslim Science

This paper investigates how medieval Islam encouraged scienti…c innovation. By granting non-Muslims a degree of religious freedom, Muslim law created competition between religions for converts and social standing. Institutionalized tolerance, coupled with initial disadvantages in the number of adherents and sophistication of theological scholarship, encouraged Muslim religious elites to promote the study of logic. The study of logic for inter-religious debates, in turn, created an environment in which science ‡ourished. Results suggest that competition, tolerance and non-religious intellectual enterprise decreased as the societies under Muslim rule became increasingly religiously homogeneous. The results highlight the role of tolerance in Islam’s medieval development and stress the importance of diversity in constraining elements resistant to innovation. Harvard University. I thank numerous individuals and seminar participants for helpful comments and discussions. A special thanks to Barry Eichengreen for encouragement, guidance and patience.