Questions on Aristotle’s Physics

Introduction

Buridan’s questions on Aristotle’s Physics survive in several redactions; the last, the “ultima lectura”, is being published in a critical edition by Michiel Streijger and Paul Bakker (from 2015). In the question form of the Paris schools, he discusses the principles of nature, motion, place, time and the infinite. Book VIII, question 12, sets out the theory of impetus: a projectile moves on because the mover has impressed on it a force proportional to its speed and quantity of matter, which only the resistance of the medium and the body’s gravity reduce. Buridan uses the same idea for the acceleration of falling bodies and suggests that God could have set the heavenly spheres in motion by an impetus at creation. Pierre Duhem made the text a centrepiece of his thesis that modern mechanics began in fourteenth-century Paris.

Connections

Builds on

• Physicsc. 350 BCE · Aristotle

More works by John Buridan

• c. 1340Summulae de dialectica