Jean, a native of Bethune, in Artois, and one of the most celebrated philosophers of the fourteenth century, flourished between 1335 and 1358. He taught in the university of Paris with great reputation, and wrote on logic, ethics, and Aristotle's metaphysics. Aventinus relates that he was a disciple of Occam; and that, being expelled Paris by the intrigues of the realists, who were at that time more influential than the nominalists, he went into Germany, where he founded the university of Vienna; but that writer is clearly in error in attributing to Buridan the founding of this institution. Buridan was the author of the well-known illustration of the doctrine of free-will by the proverb of the ass between two bundles of hay—a sophism that long perplexed the schools.