William of Ockham

William of Ockham (c. 1287–1347) was an English Franciscan friar and theologian, and to the nominalists one of the founders of their movement. He joined the Franciscans young, studied at the London school and Oxford, and never held a master’s chair, so was known as the ‘venerable beginner’. His Sentences lectures of 1317–1319 were followed by commentaries on Aristotle and Summary of Logic.

His razor tells thinkers to prefer fewest assumptions; the Latin wording, ‘entities must not be multiplied beyond necessity’, he never used. In 1324 John XXII summoned him to Avignon. A committee of theologians reviewed suspect passages without verdict.

Michael of Cesena asked him to study the bulls; he found them heretical. He slipped out of Avignon in May 1328, was excommunicated, and took refuge in Munich with Emperor Louis IV. He wrote political writings and died in April 1347 before the Black Death reached Munich.