Aristotle's Doctrine Of Predicables And Porphyry's Isagoge

Aristotle's Doctrine Of Predicables And Porphyry's Isagoge CHRISTOS EVANGELIOU 1. FOR THE PERCEPTIVE STUDENT of the history of ideas, Porphyry is an enigmatic and interesting philosopher. His thinking is clear and his Greek is unusually elegant for a writer of the third century A. D? He was able to produce excellent commentaries on Plato and Aristotle? Although he respected his renowned teacher, Plotinus, he did not always follow his teaching. 3 He was a formidable foe of Christianity and a very capable defender of Hellenism. 4 Above all, he was the author of a relatively small treatise 5 which was destined to have "a brilliant career during the Middle Ages, ''6 and a great impact on Western philosophical thought. I am referring to the famous Eisag6g~ or Isagoge, as it is known in the West. 7 Subsequent generations of commentators on Aristotle's logical works admired Por- , Porphyry's style was praised in ancient times by Eunapius, The Lives of the Sophists (London : W. Heineman, t92~), 456 and in recent times byJ. Tricot, lsagoge(Paris: J. Vrin, 1947), 7. " For a complete list of Porphyry's commentaries, see J. Bidez, Vie de Porphyre, ~d ed. (Hildesheim: G. dims, x964), 65-67. 3 For example, Porphyry defended Aristotle's theory of categories which had been criticized severely by Plotinus. On this see my paper "The Ontological Basis of Plotinus' Criticism of Aristotle's Theory of Categories," in R. B. Harris, ed., The Structure of Being: A Neoplatonic Approach (Albany: SUNY Press, 1982), 73-83. 4 Porphyry is the author of a treatise entitled Against the Christianswhich was considered a mine of anti-Christian arguments in the long struggle between Christianity and Hellenism. See A. Hulen, Porphyry'sWork Against the Christians:An Interpretation, Yale Studies in Religion, No. 1 (Scottdale, Pa.: Mennonite Press, x933), 5-1o. 5 The Isagoge'slength is less than fifteen full pages. 6 I. M. Bohefiski, Ancient Formal Logic (Amsterdam: North-Holland Publishing Co., t963), to4. 7 The Greek title is rendered into English as Introduction. [15] 16 JOURNAL OF THE HISTORY OF PHILOSOPHY 23:1 JANUARY 1985 phyry's book so much that the Isagoge was incorporated into the Organon in later antiquity, s Traditionally, dialecticians have found in Porphyry's book useful information pertaining to such philosophical methods as definition, division, demonstration and the like,9 all of which make use of the important quinque voces or ph6nai: genus, differentia, species, property, and accident? ~ During the Middle Ages and later, metaphysicians have debated the difficult questions raised in the opening paragraph of the Isagoge regarding the ontological status of "genera and species": Whether they exist in themselves or reside in mere concepts; whether they are corporeal, if they exist, or incorporeal; whether they are apart from sensible things or dependent on them?' Historians of philosophy have noticed with amazement that Porphyry's treatise was deemed worthy of attention and commentary by Greek, Latin, Byzantine , Armenian, Syrian, and Arabic commentators alike. '~ In other words, for many centuries the Isagoge had only admirers who did not hesitate to make statements like the following: "In fact Porphyry's Isagoge and his elementary commentary on the Categories are admirable introductions to the concepts of Aristotelian logic.''~3 However, in this century Porphyry has been criticized rather severely by some historians of logic and Greek philosophy ~4 who think that they have found serious logical and other errors in the Isagoge. For example, Porphyry has been accused of "Platonizing Aristotle" and "inventing the problem of universals"; he has been blamed for being "a nominalist" and "a syncretist": he has also been held responsible for "muddling" Aristotle's doctrine of the predicables by introducing certain changes which, according to his critics, have made this doctrine both non-Aristotelian and unintelligible.'5 One may wonder whether Porphyry could have avoided detection, had he really committed all these errors. On the other hand, it is not impossible that he has been accused of mistakes which he did not make. I think that this is the case, s Even as late as the nineteenth century, O. F. Owen included the Isagoge in his translation of The Organon of Aristotle (London: H. G. Bohn...