Buridan, Giovanni

BURIDAN, Giovanni. - Philosopher and scientist, b. at Béthune at the end of the 13th century or the beginning of the 14th. Rector of the Sorbonne for the second time in 1340 (the date of his first rectorship is unknown), he was still teaching there in 1358, and it is almost certain that he died shortly afterwards. A disciple of Ockham, he championed and developed his doctrines despite the disapprovals and proscriptions of 1326, 1339, and 1340. He indeed accentuated the nominalist theory of universals and upheld a singular form of voluntarism: the greater good invariably determines our choice, and the only freedom in our power is that of suspending the choice for further reflection. The legend of B.'s ass, incapable of making a determination, is not found in his writings. B.'s greatest merit lies in having divined the foundations of modern dynamics (E. Gilson). It is in fact in the nominalist school of Paris that we find the precursors of Leonardo, of Copernicus, of Galileo (P. Duhem). A special merit of B. is that he breached the Aristotelian doctrine of motion. He replaced it with the theory of the impetus impressed by the mover upon the movable body, and he intuited that without the resistance of the medium motion would continue indefinitely. Thus it happens in the sidereal rotary motion, where the impetus initially impressed by God encounters no resistances tending to annul it. The motive intelligences thus become superfluous, and the entire astronomical construction of the ancients is shaken. Also noteworthy are his observations on gravitation and the laws that govern it.

Principal works: Summulae o Compendium logicae (Paris 1487); Quaestiones in libros politicorum Aristotelis (ibid. 1500); Quaestiones super octo physicorum libros (ibid. 1500); Quaestiones in libros de anima (ibid. 1516); In metaphysicon Aristotelis quaestiones (ibid. 1518).

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