William of Ockham
General terms like “humanity” are only signs in our minds, not real things – and nothing should be assumed without a reason, unless it is self-evident, known by experience or vouched for by Scripture.
Placement
Nominalist: universal concepts are mere signs. His rule to posit nothing without a reason – unless it is self-evident, known by experience or vouched for by Scripture – was later called “Ockham’s razor”; the formula “entities are not to be multiplied” is not his.
Key ideas
- Ockham's razor
- Nominalism
Influence
Influenced by 1
Aristotle
influenced by ✓
Ockham commented on Aristotle’s logic and Physics and read the categories as classes of terms, admitting only substances and qualities as distinct things (Summa logicae, c. 1323). William of Ockham, Expositio in libros Physicorum; Summa logicae I (c. 1323); SEP “William of Ockham”
Aristotle › 384–322 BCE
Criticism
Criticized by 1
John Buridan
criticised by
Buridan shared Ockham’s nominalism but rejected his reduction of quantity to substance and quality, holding quantity to be a really distinct accident. John Buridan, Quaestiones super octo libros Physicorum I; J. Zupko, John Buridan: Portrait of a Fourteenth-Century Arts Master, 2003
Evidence: AI draft
John Buridan › c. 1300–1360
Criticizes 2
Thomas Aquinas
criticised
Ockham rejected Aquinas’ real distinction between essence and existence and the intelligible species in cognition as entities without need (Summa logicae III-2 c. 27; Reportatio II). William of Ockham, Summa logicae III-2 c. 27; Reportatio II qq. 12–13; SEP “William of Ockham”
Evidence: AI draft
Thomas Aquinas › c. 1225–1274
John Duns Scotus influenced by
influenced by ✓
Ockham took over Scotus’ distinction between intuitive and abstractive cognition and his univocal concept of being, while rejecting common natures and the formal distinction. William of Ockham, Ordinatio, prologue q. 1; I d. 2; SEP “William of Ockham”
criticised
Ockham rejected Scotus’ common natures and his formal distinction outside God: only individuals exist, and universals are concepts (Ordinatio I d. 2 q. 6). William of Ockham, Ordinatio I d. 2 qq. 1, 6; SEP “William of Ockham”
Evidence: AI draft
John Duns Scotus › c. 1266–1308
Works
- c. 1323Summa logicae
Terminist logic: universals are signs, not things.
Position
Ockham is the leading figure of nominalism: only individual things exist. Universals are not entities in or behind things but signs in the mind and in language that stand for many individuals. Much of his work applies a principle of economy – do not assume more entities than necessary – later called “Ockham’s razor”. Since God is absolutely free and could have made the world otherwise, the order of nature is contingent and must be learned from experience. In politics he argued against papal absolutism and for limits on spiritual power. His logic and empiricism opened the “modern way” in late medieval thought.
Life & context
Born around 1287 in Ockham, Surrey, William became a Franciscan and studied in Oxford. Summoned to Avignon in 1324 to answer for his teaching, he sided with his order’s general in the dispute over apostolic poverty against Pope John XXII and fled in 1328 to Emperor Louis of Bavaria. He spent his remaining years in Munich writing political polemics and died there around 1347.
Further main works
- Commentary on the Sentences (c. 1318)
- Quodlibeta septem (c. 1324)
- Dialogus (c. 1334–1346)
- Breviloquium (c. 1340)
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