William of Ockham (also Occam or any of several other spellings) (c. 1285–1349) was an English Franciscan friar and philosopher, from Ockham, a small village in Surrey, near East Horsley. As a Franciscan, William was devoted to a life of extreme poverty. A pioneer of nominalism, some consider him the father of modern epistemology and modern philosophy in general, because of his strongly argued position that only individuals exist, rather than supra-individual universals, essences, or forms, and that universals are the products of abstraction from individuals by the human mind and have no extra-mental existence. Ockham is sometimes considered an advocate of conceptualism rather than nominalism, for whereas nominalists held that universals were merely names, i.e. words rather than existing realities, conceptualists held that they were mental concepts, i.e. the names were names of concepts, which do exist, although only in the mind.

Ockham is also considered one of the greatest logicians of all time. One important contribution that he made to modern science and modern intellectual culture was through the principle of parsimony in

Summoned to Avignon in 1324 by Pope John XXII on accusation of heresy, Ockham spent four years there in effect under house arrest while his teaching and writing were investigated. During this period, at the request of Brother Michael of Cesena, head of the Franciscan order, he investigated the controversy between the Franciscans and the Papacy on the doctrine of apostolic poverty, which had become central to Franciscan doctrine, but which was considered highly dubious and possibly heretical by both the Papacy and the Dominican order. He concluded that Pope John XXII was a heretic, a position that he later put forth in writing.

Before a conclusion was reached about the heresy or orthodoxy of Ockham's philosophy, he fled Avignon on May 26, 1328 with Michael of Cesena and a few other friars. They sought the protection of Emperor Louis IV of Bavaria. After his declaration against the pope, Ockham is believed to have been excommunicated, although historical sources vary. He spent much of the remainder of his life writing about political issues, including the relative authority and rights

He died in a convent in Munich, Bavaria (now Germany), possibly as a result of the Black Death.

Works

Philosophy

• Summa logicae (Sum of Logic) (before 1327), Paris 1448, Bologna 1498, Venice 1508, Oxford 1675.
• Quaestiones in octo libros physicorum, (before 1327), Rome 1637.
• Summulae in octo libros physicorum, (before 1327), Venice 1506.
• Quodlibeta septem (before 1327), Paris 1487.
• Expositio aurea super totam artem veterem: quaestiones in quattuor libros sententiarum, Lyons 1495, Bologna 1496.
• Major summa logices, Venice 1521
• Quaestiones in quattuor libros sententiarum, Lyons, 1495.
• Centilogium theologicum, Lyons 1495.

Religion

• Questiones earumque decisiones, Lyons 1483.
• Quodlibeta septem, Paris 1487, Strassburg 1491.
• Centilogium, Lyons 1494.
• De sacramento altaris and De corpore christi, Strassburg 1491, Venice 1516.
• Tractatus de sacramento allans

Politics

• Opus nonaginta dierum (1330-1332), Leuven 1481, Lyons 1495.
• Dialogus…de imperatorum et pontificum potestate, Lyons 1495.
• Compendium errorum Joannis XXII papae (1335–38), Paris 1476, Lyons 1495.
• Defensorium contra errores Johannem XXII papae (1335–39) Venice 1513.
• Super potestate summi pontificis octo quaeslionum decisiones (1339–42).
• Tractatus de dogmatibus Johannis XXII papae (1333–34).
• Adversus errores Johannis XXII, Leuven 1481, Lyons 1495.
• Epistola defensoria, Venice 1513.
• Decisiones octo quæstionum (after 1339), Lyons 1496.
• Dialogus in tres partes diatinctus (1342–43), Paris 1476.
• De jurisdictione imperatoris in causis matrimonialibus, Heidelberg 1598.
• De electione Caroli IV (last work)

In fiction

William of Ockham served as an inspiration for the monastic detective William of Baskerville in Umberto Eco's The Name of the Rose, who used logic in a similar manner and, like William of Ockham, had faced charges of heresy.

See also

• Oxford Franciscan school
• History of science in the Middle Ages
• Occam programming language