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Roger Bacon

c. 1219–1292

A first way ina deliberate simplification – the portrait says more

Knowledge of nature must rest on experiment and mathematics, not just on books – and scholars should read texts in their original languages.

Placement

Medieval & Scholastic · Northern Europe · Science, Epistemology, Language

Franciscan “Doctor mirabilis”: knowledge of nature must rest on mathematics, optics and experience – and scholars should learn the original languages.

Key ideas

  • Experimental science (scientia experimentalis)
  • Mathematics as key to the sciences
  • Optics

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Influence

Influenced by 4

  • Aristotle

    influenced by

    Bacon was among the first masters to lecture on Aristotle’s natural philosophy and Metaphysics at Paris in the 1240s; his question commentaries from these years survive. Roger Bacon, Quaestiones supra libros Physicorum; Quaestiones supra Metaphysicam (Opera hactenus inedita); SEP “Roger Bacon”

    Evidence: AI draft

    Aristotle › 384–322 BCE

  • Ibn al-Haytham (Alhazen)

    influenced by

    Roger Bacon based the theory of vision in the Perspectiva of his Opus maius (1267) largely on Ibn al-Haytham’s Optics in its Latin translation, De aspectibus. Roger Bacon, Opus maius, part V (1267); D. C. Lindberg, Theories of Vision from al-Kindi to Kepler (1976); SEP “Roger Bacon”

    Evidence: AI draft

    Ibn al-Haytham (Alhazen) › c. 965–1040

  • Ibn Sina (Avicenna)

    influenced by

    Bacon ranked Avicenna highest among Aristotle’s followers and, with him, held the agent intellect to be separate from the soul – for Bacon, God himself (Opus maius, 1267). Roger Bacon, Opus maius (1267); É. Gilson, ‘Les sources gréco-arabes de l’augustinisme avicennisant’, AHDLMA 4 (1929); SEP “Roger Bacon”

    Evidence: AI draft

    Ibn Sina (Avicenna) › 980–1037

  • Ibn Rushd (Averroes)

    influenced by

    Bacon used Averroes’ commentaries in his Paris lectures on Aristotle in the 1240s and cited him as an authority in the Opus maius (1267). Roger Bacon, Quaestiones supra libros Physicorum; Opus maius (1267); SEP “Roger Bacon”

    Evidence: AI draft

    Ibn Rushd (Averroes) › 1126–1198

Works

  • 1267Opus Majus

    An encyclopedic plea to the pope for languages, mathematics, optics and experimental science.

Position

Bacon named four causes of human ignorance: unworthy authority, long custom, popular opinion and the concealing of one’s ignorance behind a show of wisdom. As remedies he urged the study of Greek, Hebrew and Arabic, so that scholars could read their sources in the original; mathematics, which he called the gate and key of the sciences; optics, the science of light and vision; and an “experimental science” that tests conclusions against experience and discovers new truths. All this was to serve Christian wisdom. Later centuries made him a legendary magician and a forerunner of modern science – both images exaggerate, yet his program was remarkable.

Life & context

Roger Bacon was born in England around 1219 and studied at Oxford and Paris, where in the 1240s he was among the first to lecture on Aristotle’s writings on nature. Around 1257 he became a Franciscan. In 1267, at the request of Pope Clement IV, he sent him his major works. A later, uncertain report says his order confined him. He died around 1292, probably in Oxford.

Further main works

  • Opus Minus (1267)
  • Opus Tertium (1267)
  • Compendium of the Study of Philosophy (c. 1271)

Sources: Wikipedia · Wikidata

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