In medieval Christian thought, intellectual activity and gainful employment were incompatible. Selling “words and knowledge” [10. 211] was frowned upon, since knowledge (like time, in which tradesmen and money lenders speculated) belongs to God. It was only in the cities of the high and late Middle Ages that the view became widespread that jurists, physicians, teachers in schools and universities, and other intellectuals were engaged in intellectual work and deserv…