Predication: A Study Based in the ARS Logica of John of St. Thomas

PREDICATION: A STUDY BASED IN THE A.RS LOGICA OF JOHN OF ST. THOMAS Introduction l ~HIS is a study of predication based upon the Ar~ Logica of John of St. Thomas. The importance of a study of predication depends in part on the presentday philosophical revival. On every side there are signs demonstrating a renewed interest in philosophy: attempts of scientists to establish contact with a philosophy of nature, as at the notable Darwin Centennial at the University o£ Chicago; and even more striking, the revival of metaphysics, vague but strong enough to bring about changes in the curriculum of such institutions as the Massachusetts Institute of Technology and The United States Military Academy. In this revival, logic is important because it has never been abandoned to a serious extent and has remained a respectable tool for science, so much so that the very revival of philosophy often is under the guise of a logic. Logic remains today what it has ever been: a tool of reason, and as such it is indispensable to the advance of science, to the struggle to give certitude to science, and even to the re-emergence of metaphysics. Predication, however, is the key-stone of logic, affecting every important logical problem, for predication is the fundamental tool of reason. The Ars Logica of John of St. Thomas has been selected as the central source, not, however, as the principal source. Our aim is not to give an historical sketch of the teachings of John of St. Thomas on predication, but to get at the truth of the matter. This truth is best expressed by St. Thomas Aquinas, who is our principal source. Nevertheless, it is convenient to centralize our topic around the Ars Logica for three reasons. First, John of St. Thomas is faithful to the 260 PREDICATION: A STUDY BASED IN " ARS LOGICA " 261 teachings of his master, St. Thomas, to an exceptional degree.1 Second, he summarizes a great deal of the Scholastic tradition.2 Third, his writings are exercising considerable influence among modern logicians.3 A better basis is hard to find. SECTION ONE THE GENERAL NOTION OF PREDICATION The Definition The word " predication " 1 has enjoyed a variety of meanings . In a very loose sense, it has been used to signify the attribution of one thing to another, no matter how such an attribution came about. It is common to read of the predication of a major term of a minor term in a syllogism; 2 and among the Greeks it meant a legal charge; 3 for the Romans, predica1 So much so that it is the opinion of Klubertanz that John of St. Thomas is a founder of Thomism. Cf. Klubertanz, George, S. J., Being and God According to Contemporary Scholastics (Modern Schoolman, 1954, p. 4). For the absurdity of this position, cf. O'Brien, Thomas C., 0. P., Reflexion on the Question of God's Existence in Contemporary Thomistic Metaphysics (The Thomist, 1960), pp. 1718 , and 85, note 349. Historians such as Copleston make no suggestion of it. Cf. A History of Philosophy (London, 1953). 2 This is especially true of the Scholastic tradition after the time of St. Thomas. 2 The logic section of Elements Philosophiae Aristotelico-Thomisticae by J. Gredt (Herder, 1937) is merely a summary of the Ars Logica. R. Schmidt, S. J., in his review of The Material Logic of John of St. Thomas (New Scholasticism, April, 1956) writes: "The importance of John of St. Thomas (1589-1644) in modern Thomistic thought can hardly be exaggerated. The dominant tradition of Thomism comes from him, and through him from Cajetan. And the part of his philosophy in which his influence has been greatest is logic" (p. ~3~). Cf. also M. Adler: Solution to the Problem of Species (The Thomist, April 1941), p. ~90 note 16; p. ~93 note ~0; and Simon's Maritain's Philosophy of the Sciences (The Thomist, January 1943), p. 88. Among non-Scholastics, cf. Intentional Logic by H. B. Veatch (New Haven, 195~), p. ix. 1 The gr. Kanryopla, latin praedicatio. The verb forms are Kanrtop€w and praedicare. In latin, dicere, dictum, etc. often are used as synonyms, frequently...