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Siger of Brabant


Aristotelian and Averroist philosopher; b. Duchy of Brabant, c. 1240; d. Orvieto, between 1281 and 1284. He was a secular cleric and canon of St. Paul in Liège.

Life. After studying the liberal arts in Paris, Siger became master of arts and taught philosophy at the university. In 1266 he was cited by the papal legate, Simon of Brion, as the leader of a rebellious faction in the arts faculty. At about the same time he became the leader of a group of professors, among whom were boethius of sweden (Dacia) and Bernier of Nivelles, who taught an aristotelianism influenced by Averroës and on some points contrary to the Christian faith. In 1270 the bishop of Paris, Étienne tempier, condemned some of their teachings. Despite the official action against his doctrines, Siger's influence at the university grew. In 1271 he was again involved in a dispute in the faculty of arts, this time over the election of the rector of the university. On Nov. 23, 1276, Simon du Val, the inquisitor of France, summoned Siger of Brabant, Bernier of Nivelles, and Goswin of La Chapelle to appear before him to answer the charge of heresy. On March 7, 1277, the bishop of Paris condemned 219 propositions, among which are the heterodox teachings of Siger's Latin Averroism. Siger fled to the papal curia at Orvieto, where he died, stabbed by a demented secretary.

Siger was a philosopher of importance in the thirteenth century. He was called Siger the Great (Magnus ), and Dante placed him among the wise men in paradise, with St. Thomas Aquinas speaking his eulogy. According to A. nifo, writing about 1500, Siger was the founder of the Averroist school of philosophy.

Teaching. Like Averroës, Siger separated philosophy from religion. While accepting the truth of the Catholic faith, he insisted on the right of the philosopher to follow human reason to its inevitable conclusions, even though, in his view, it sometimes contradicts revelation. For example, he taught the eternity of the world as a necessary conclusion of philosophy, though it is contrary to faith. He did not acknowledge a double truth, one for philosophy and another for religion; however probable or even necessary he thought philosophical conclusions contrary to faith may be, he never called them true. The aim of the philosopher, he said, is not so much to discover the truth but what the great philosophers of the past, and especially Aristotle, thought (De anima intell. 7, ed. P. Mandonnet 2:164). St. Thomas opposed this conception of philosophy: "It is not the aim of philosophy," he wrote, "to know what men have thought but what the truth of things is" (In 1 cael. 22.8).

Siger's doctrine of being or reality is that of Aristotle as interpreted by Averroës. Opposing St. Thomas, Siger denied a composition of essence and existence in creatures. Existence, he said, is of the essence of creatures; for example, it is essential for man to exist. All species are eternal and necessary; individuals in the species are alone contingent. Siger granted a distinction between the terms "thing" (res ) and "being" (ens ), but in his view they signify the same reality in different ways. When one says that something is a being or exists, he means that it enjoys actuality; when he calls it a reality, he means that it possesses being in a stable manner.

Siger's notion of man and the human soul is also derived from Averroës's interpretation of Aristotle. According to Siger, each man is a substance composed of matter and a form, or soul, endowed with vegetative and sense powers. The intellect is an eternal, spiritual substance, separate from matter, and possessed in common by the human race. It is composed of two parts, the agent and possible intellects. This intellect may be said to belong to each man because it operates in him and uses his sense powers. The will, a faculty of the separate intellect, is passive and determined by motives presented to it by the intellect. The intellect is immortal, but individual souls of men are not. There are moral sanctions in the present life but not in a future one; good deeds are their own reward; evil ones bear their own punishment.

In a lost work, De intellectu, Siger later held that God is the agent intellect. The human intellective soul is composed of the possible intellect, which is one for all men, and the human cogitative power. Because of this union, the intellect is multiplied and diversified, and it can be said to be the substantial form of man, giving him his specific rational being. In another lost treatise, De felicitate, Siger, following Averroës, held that man's supreme happiness in this life consists in the possible intellect's knowledge of the essence of the agent intellect, or God.

Works. Commentaries on Aristotle: Quaestiones in physicam, in metaphysicam, in tertium de anima; Compendium de generatione et corruptione. Questions on Aristotle's Libri naturales and Politics are lost. A collection of seven other commentaries on Aristotle in maunuscript Munich 9559 is of disputed authenticity. Independent treatises are as follows: Quaestiones logicales; Quaestio utrum haec sit vera: homo est animal, nullo homine existente; Impossibilia; Sophisma "Omnis homo de necessitate est animal"; Quaestio de necessitate et contingentia causarum; Quaestiones naturales; Quaestio de aeternitate mundi; Tractatus de anima intellectiva; Quaestiones morales. Lost treatises are as follows: De intellectu; De motore primo; Liber de felicitate.

See Also: averroism, latin; double truth, theory of.

Bibliography: Editions. p. f. mandonnet, Siger de Brabant et l'averroïsme latin au XIII e siècle, 2 v. (2d ed. Les Philosophes belges 67; Louvain 190811). f. van steenberghen, Siger de Brabant d'après sea oeuvres inédites, 2 v. (ibid. 1213; Louvain 193142). De aeternitate mundi, ed. w. j. dwyer (Louvain 1937). Questions sur la métaphysique, ed. a. graiff (Louvain 1948). Literature. f. van steenberghen, "Nouvelles recherches sur Siger de Brabant et son école," Revue philosophique de Louvain 54 (1956): 130147. a. maier, "Nouvelles questions de Siger de Brabant sur la Physique d'Aristote," ibid. 44 (1946): 497513. a. zimmermann, Die Quaestionen des Siger von Brabant zur Physik des Aristoteles (Doctoral diss. U. of Cologne 1956). j. j. duin, La Doctrine de la Providence dans les écrits de Siger de Brabant (Louvain 1954). g. da palma, La dottrina sull'unità dell'intelletto in Sigieri di Brabante (Padua 1955). b. nardi, Sigeri di Brabante nel pensiero del Rinascimento italiano (Rome 1945). a. maurer, Medieval Philosophy (New York 1962). É. h. gilson, History of Christian Philosophy in the Middle Ages (New York 1955). f. c. copleston, History of Philosophy, v. 2. Medieval Philosophy, Augustine to Scotus (Westminster, Md. 1950). l. hÖdl, Lexikon für Theologie und Kirche, 10 v. (Freiburg 195765) 9:746747.

[a. maurer]

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