ABSTRACT
These two categories, with their classical pedigree, remained in tension throughout the Western Middle Ages. With few exceptions, the official philosophical learning of the universities (from the thirteenth century onward) should be classified as exoteric, insofar as it formed the subject of open lectures. It was restricted in the sense that these lectures and their texts required knowledge of Latin, but there was no ban on expression of the ideas in the vernacular. Esoteric knowledge occupied a different place, one that, by its very nature, had an ambiguous status. Our evidence for it comes from written texts that, therefore, tended to transcend the secretive, word-of-mouth traditions supposedly characteristic of such knowledge. Thus, writings by Roger Bacon in the thirteenth century, or Books of Secrets from the later Middle Ages, purported to reveal arcane knowledge of a practical kind-the refining of metallic ores, for example, or the construction of mechanical or optical wonders-that had hitherto, they claimed, been the possession of the privileged few. In this way, occult esoteric knowledge and the technical secrets of medieval craft guilds were not much different from each other and stood in stark contrast to exoteric knowledge even (or especially) when “revealed” as “secrets” to the rest of the world.
