c. 1285-c. 1349

William Ockham, known as William of Ockham (or Occam), had a significant effect on the decline of medieval Scholasticism, the separation of church and state, and the eventual rise of scientific thinking. Although his writing and teaching led to his excommunication, the importance of his thought was later recognized and he is regarded as a major philosopher of the Church. He is best known for his use of the Law of Economy, known as Ockham's Razor.

Ockham was trained in logic and, at an early age, became a member of the Franciscan Order. He studied at Merton College of Oxford University and taught there from 1309-1319. His ideas were controversial, and he left without his master's degree. He taught in Paris from 1320-23 and published a number of writings opposing the Church's involvement in secular political activities, thereby angering the Papal Court, which was...