(John), a native of Bethune, in Artois, was one of the most celebrated philosophers of the 14th century. He taught in the university of Paris with great reputation; and wrote commentaries on logic, morality, and Aristotle's metaphysics. Aventinus relates, that he was a disciple of Ockam; and that, being expelled Paris by the power of the Realists, which was superior to that of the Nominalists, he went into Germany, where he founded the university of Vienna. From him came the proverb of the *as* of Buridan, so famous in the schools. Buridan supposed an hungry ass fixed at an exactly equal distance between two bushels of oats; or an ass, as much perplexed by thirst as hunger, between a bushel of oats and a pail of water, each of them acting equally on his senses. Having made this supposition, he desired to know what the ass would do? If he was answered that he would remain immovable, then he concluded he would die of hunger between two bushels of oats, or of both hunger and thirst, with both corn and water within his reach. This appeared absurd, and brought the laughter on his side; but if it was replied, that the ass would not be so stupid as to die of hunger or thirst in such a situation. Then (said he), the ass has free will, or is it possible that of two equal weights one should outweigh the other? These two consequences appeared equally absurd; and thus Buridan, by this sophism, perplexed the philosophers, and his *as* became famous in the schools.