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 6–7; Louvain 1908–11). f. van steenberghen, Siger de Brabant d'après sea oeuvres inédites, 2 v. (ibid. 12–13; Louvain 1931–42). 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): 130–147. a. maier, "Nouvelles questions de Siger de Brabant sur la Physique d'Aristote," ibid. 44 (1946): 497–513. 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 1957–65) 9:746–747.

[a. maurer]

SIGER OF BRABANT

(b. Brabant, ca. 1240; d. Orvieto, Italy, 1281/1284)

philosophy.

Nothing is known of Siger’s birthplace, his family, or his early education. He arrived in Paris probably between 1255 and 1260, was admitted to the Picard nation of the University of Paris, and became master of arts between 1260 and 1265. His name is first cited in a document dated 27 August 1266, in which he appears as a boisterous and pugnacious young teacher at the Faculty of Arts. He received a special rebuke in Thomas Aquinas’ De unitate intellectus (1270); and on 10 December 1270 the bishop of Paris, Étienne Tempier, condemned thirteen heterodox propositions taken from the writings of Siger and his partisans. After 1270 Siger tempered his doctrinal positions, but remained the leader of the dissident minority party in the Faculty of Arts. Later he was summoned by the inquisitor of France but fled in late 1276 with two other teachers and took refuge at the papal court, the tribunal of which was reputedly more lenient than that of the inquisitors. (On 7 March 1277 Tempier, with Siger’s teaching particularly in mind, condemned 219 propositions.) At the papal court, Siger was placed under house surveillance in the company of a cleric. Sometime during the pontificate of Martin IV (1281–1285), the cleric, in a fit of madness, stabbed Siger to death. John Peckham attests his death in a letter dated 10 November 1284.

Dante esteemed Siger as the victim of attacks by conservative theologians. Although Siger’s career ended prematurely, his historical role was nevertheless fundamental because of the reactions he provoked in university circles — and on such men as Bonaventure, Thomas Aquinas, Albert the Great, and John Peckham.

On the basis of his writings discovered to date, it is known that Siger was concerned primarily with metaphysics and psychology, and secondarily with logic and natural philosophy; several questions on ethics also have been discovered. His contributions to science can be found in his writings on psychology and natural philosophy, in which areas connections can be made between philosophy and science.

Siger’s writings on psychology are devoted to problems of the intellective soul, and these are treated in an exclusively philosophical manner: the works contain only those few elements of descriptive psychology that are indispensable for formulating the philosophical problems.

Siger wrote several works on natural philosophy. Of the three Quaestiones naturales found in Paris, the first is purely philosophical and deals with the uniqueness of the substantial form: the second defends the Aristotelian principle “Everything that moves is moved by something else”: and the third discusses the problem of gravity, which is resolved in the spirit of Ibn Rushd.

Six other Quaestiones naturales have been found in Lisbon. The third and sixth are purely philosophical, and two others are patterned on Aristotle’s pseudophilosophical hypotheses on the “natural place” of simple bodies (the first question) and on the influence of the heavens (orbis) in human generation (the fourth question), which are of no interest for experimental science. Only the second and fifth questions have some scientific taste. The second and fifth questions have some scientific taste. The second interprets an experiment in physics: “If a lighted candle is placed in a vessel put on water, why does the water then rise in the vessel?” Siger’s answer is inspired by Aristotle. The candle warms the air, which then rises to the top of the vessel. Because a vacuum is impossible and water is fluid, the water rises (remaining in contact with the air), compresses the air, and thus increases its own ascending motion. But the vessel would shatter if placed mouth down on the earth. Since the latter cannot rise because of its cohesion and weight. The fifth question is a brief, abstract discussion of the paradox of Achilles and the tortoise.

In Impossibilia the problem of gravity is again examined in chapter 4. After a long discussion, in which he rejects the opinions of Albertus Magnus and of Thomas Aquinas, Siger again adopts (but modifies) Ibn Rushd’s thesis. The entire discussion is developed according to Aristotelian physics (with all its prejudices).

De aeternitate mundi treats the eternity of mankind in a purely philosophical context. Compendium de generatione el corrupione, a fragment of which has been discovered in a manuscript in Lilienfeld, Austria, is a brief, unoriginal analysis of Aristotle’s treatise. Almost all of the twenty-four Quaestiones super libros I et II Physicorum, discovered at the Vatican, deal with purely philosophical problems. The only questions of possible interest from a scientific viewpoint are II, 1 and 2, on the natural movement of light and heavy bodies (which is explained in the same way as in the other writings), and II , 5, in which Siger explains that musica, perspectiva, and astrologia are intermediary between the purely natural and mathematical sciences.

Siger’s contribution to experimental science seems insignificant. Even those problems that could have been treated scientifically were given a philosophical explanation and were solved without originality by relying on the principles of Aristotle and Ibn Rushd. If the commentaries of Munich MS 9559, which have been arrtibuted to him by Martin Grabmann, were truly by Siger, this assessment would be different, for then Siger would be the author of an important series of commentaries on natural philosophy in which many scientific questions are discussed. Formerly the author accepted Grabmann’s attribution; but serious difficulties have since been raised concerning the authenticity of several commentaries, and it seems preferable not to take them into account here.

BIBLIOGRAPHY

I. Original Works. All the works of Siger quoted in the article are in B. Bazán, ed., Signer de BRabant Quaestiones in tertium de anima. De anima intellectiva. De aeternitate mundi (Louvain, 1972), and B. Bazán, ed., siger de Brabant. Écrits de logique, de morale et de physique (Louvain, 1974).

II. Secondary Literature. See P. Mandonnet, Siger de BRabant et l’averroïme latin au XIIIe siècle, 2nd ed., 2 vols. (Louvain, 1908–1911); F. Van Steen-berghen, Siger de BRabant d’aprés ses oeuvres inédites, 2 vols. (Louvian, 1931–1942); La philosohie qu XIIIe siècle (Louvain, 1966), 357–402; and Introduction á létude de la philosophie médiévale (Louvain, 1974), passim (see Table onomaztique, p.603).

F. Van Steenberghen

Siger of Brabant (Averroist philosopher): see AVERROISM.