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Porphyry (c. 232–c. 304)

(c. 232c. 304)

Porphyry, one of the principal founders of Neoplatonism, was born of Syrian parents at Tyre. He studied philosophy at Athens. In 263 he went to Rome, joined the group that regarded Plotinus as its master, and, apparently some years after Plotinus's death, took over his school. He died some time in the first six years of the fourth century.

Porphyry can be called a founder of Neoplatonism because, while the philosophy he upheld was in the main that of Plotinus, he made it possible for this philosophy to become, as it did, an institution throughout the Roman Empire. He arranged Plotinus's lectures for publication in their present form; he defended and developed their content in independent works of his own; third, he enabled some of the much more systematic, not to say more teachable, philosophy of Aristotle to be included even by Platonic professors in a university curriculum.

In the so-called Sententiae ad Intelligibilia Ducentes (Aids to the Study of the Intelligibles; a short, difficult summary, incomplete as we have it, of Neoplatonism) he presents methodical proofs of two Plotinian theses which were unacceptable to the more conservative Platonists and to Porphyry himself when he first came to Rome: the independence and priority of the One to Being or Intellect, and the identity of Intellect or Thought with its objects. Plotinus, however, had been ambiguous over the extent to which the lower hypostases, Intellect (embracing the Platonic forms) and Soul (embracing nature and the Aristotelian forms), each existed in its own right. It is the monistic strand that seems to dominate in Porphyry: Everything that is not the One is an appearance of the One and is the result of the inadequacy of our thought about the One. The serious consequence of this doctrine is for the ordinary notion of personality. The individual, embodied soul and intellect, themselves appearances (he also calls them parts) of some universal soul and intellect, will be unreal; Porphyry calls the individual soul "the soul in a relation"for it is related to a bodywhich implies its nonsubstantiality according to Aristotle's doctrine of categories. This consequence was vigorously challenged by Iamblichus. Union with the One can be achieved, according to Porphyry, by the unaided effort of intellect, but we do not have enough evidence to know how he met the philosophical problems of this thesis even if he had a consistent doctrine about it.

Porphyry's ethics followed Plotinus in stressing the universal equation between pursuit of the good, becoming what one "essentially" is, the self-awareness that accompanies thought, and "reversion" to the "cause" of one's being. Evil, together with matter, was the result of a "deviation from reality." In schematizing Ennead I 2 [19], Porphyry gave Plotinus's scale of virtues a nomenclature which became conventional for later Neoplatonists. A, the virtues of the soul, are (1) civic, (2) purificatory; B, the virtues of the intellect, are (3) contemplative, (4) paradigmatic. Less abstractly and on less philosophical grounds he was attracted like many Neoplatonists by the asceticism and taboos of Pythagoreanism.

Nothing has survived of a book that Porphyry wrote comparing Platonism and Aristotelianism. It undoubtedly maintained that there was no substantial conflict between the two, which was commonplace for Platonists of the empire. His commentaries on Plato have perished too; so have those on Aristotle, except for the introduction to the Categories known as the Isagoge and an elementary commentary on the same work. But his views were often quoted; and it is clear that what is distinctive about his treatment of Aristotle is twofolda facility in expounding him without trying to Platonize him or to score against him, and a remarkable gift of clear exposition that does not depend (as it does in some later commentators) on ignoring the difficult issues. Most of the formulas that aimed at accommodating the metaphysical presuppositions of Aristotle's logic to Platonism had probably been worked out already. But since it was only the metaphysics that was objectionable, the way was open to the full acceptance of a purely formal logic. This meant not the Aristotelian logic of terms from which the nonexistent, the negative, and the particular were excluded, but something roughly equivalent to the Boolean algebra of classes.

This logic without metaphysics is roughly, too, what we find in Porphyry; and it is what has sometimes been inaptly called Porphyry's nominalism. With some debt to the Stoics, it enabled logic to develop as an autonomous science. For his Isagoge was translated into Arabic and Syriac as well as Latin, and his more advanced work was incorporated in Boethius's logic. The Isagoge is traditionally said to have made species a fifth predicable in place of definition. If it had it would have misrepresented Aristotle by implying that the subject was not a universal term, like those of the other predicables, but a particular. The implication might not have disturbed Porphyry, but in fact the Isagoge, or Quinque Voces, is not about predicables but what it says it is about, the five words that are essential to the understanding of the Categories. It does, however, introduce "inseparable accidents" which are an uneasy intermediate between essential attributes and pure or separable accidents.

Porphyry was a man of wide learning and wide interests. He studied many of the religious beliefs and practices with which he came into contact, and though generally sympathetic to them as various if inferior ways to salvation, he was renowned for centuries as the author of a detailed work against the Christians. But this and ventures of a more or less occultist natureallegorical interpretations of poetry, descriptions of the soul's "vehicles," and the likehave mostly survived only in statements from controversial sources; and while respectable as philosophy in their day they are of small philosophical interest in the modern sense.

See also Logic, History of; Neoplatonism; Plotinus.


Porphyry's "Life of Plotinus" is included in editions of Plotinus' works.

Sententiae ad Intelligibilia Ducentes (Aids to the study of the intelligibles), edited by Erich Lamberz. Leipzig, 1975.

Opuscula Selecta, edited by A. Nauck. Leipzig, 1886, rpr. 1963.

On Abstinence from Killing Animals. Translation and commentary by Gillian Clark. London, 2000.

Isagoge, with Boethius' translation. In Commentaria in Aristotelem Graeca. Vol. IV, Part I, edited by A. Busse. Berlin, 1887.

Porphyry Introduction (Isagoge). Translation and commentary by Jonathan Barnes. Oxford, 2003.

Porphyrii Fragmenta, edited by Andrew Smith. Leipzig, 1993.

On Porphyry's life and works see:

Beutler, R. "Porphyrios." No. 21 in Pauly and Wissowa, Realencyklopädie der classischen Altertumswissenschaft. Vol. XXII, Sec. 1. Stuttgart, 1953.

Bidez, J. Vie de Porphyre, Le philosophe néo-platonicien. Ghent, 1913, rpr. 1964.

Dörrie, H., et al. Porphyre. Vandoeuvres-Genève, 1966.

Smith, Andrew. Porphyry's Place in the Neoplatonic Tradition. The Hague, 1974.

Smith, Andrew. "Porphyrian Studies since 1913." Aufstieg und Niedergang der Römischen Welt II 32 (1987): 717773.

Zambon, Marco. Porphyre et le Moyen-Platonisme. Paris, 2002.

A. C. Lloyd (1967)

Bibliography updated by Andrew Smith (2005)

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