Ockham inherited significant contributions from Walter Burley’s Treatise on Suppositions. However, the criticism of Ockham’s Summa logicae by Burley in his De puritate artis logicae shows their dramatic differences. For both, supposition is the characteristic of a term as it functions in a proposition, whereby it refers to a thing (Personal Supposition), to a concept in the mind (Simple Supposition), or to itself as a spoken or written term (Material Supposition). The supposition of a term tells us for what it stands or supposits. In the proposition ‘‘A man is running,’’ ‘‘man’’ stands for any man who is presently running. In the proposition ‘‘Man is monosyllabic,’’ ‘‘man’’ supposits for the word ‘‘man.’’ In the proposition ‘‘Man is an animal,’’ ‘‘man,’’ according to Walter Burley, supposits or stands for the universal essence of man. For Ockham, in the same proposition ‘‘man’’ stands for concrete individual men. For William, there is no universal essence or reality in men, as Burley contends. Men are, for Ockham, essentially alike, and they are essentially alike prior to any action of our minds; yet, there is no essential ‘‘likeness’’ in them. Ockham’s theory of supposition in this case presupposes his theory of uni-versals. He denies the exaggerated realism he found in Burley’s early writings. It is the same exaggerated realism that Walter also defends in his later De puritate where he admits that universal essences are in individuals. Ockham’s theory of supposition extends to all areas of scientific study.
World History
