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AVERROES ° (Abu al-Walid Muhammad ibn Rushd ; 1126–1198), qadi, jurist, noted physician, and one of the greatest Islamic philosophers. Averroes, who lived in Spain, is best known as the outstanding commentator of the medieval period on Aristotle's works. He commented on most of Aristotle's works and on five of them composed three different kinds of commentaries – long, middle, and short or epitome. He also wrote a commentary on Plato's Republic (trans. R. Lerner, 1974), an epitome of Ptolemy's Almagest, and commentaries or paraphrases on logical, scientific, and medical writings of authors such as *Galen, *Alexander of Aphrodisias, al-*Farabi, and *Avicenna, and on a book on the principles of Islamic jurisprudence by al-*Ghazālī. His major independent work was Tahāfut al-Tahāfut ("The Incoherence of the Incoherence," trans. S. van den Bergh, 1954), a defense of Islamic Aristotelian philosophy against the attacks made on it by al-Ghazālī in his Tahāfut al-Falā sifa ("The Incoherence of the Philosophers," trans. M.E. Marmura, 1997). In addition he wrote short treatises on the relationship of philosophy, religion, and society (see G.F. Hourani (trans.), Averroes on the Harmony of Religion and Philosophy, 1961); some medical works; and works on astronomy and Islamic law.

Philosophic Teachings

Averroes' views on the position of the philosopher in society account for some of the main characteristics of his writings. He holds that it is incumbent upon philosophers to observe the religious law; but this law contains pointers to philosophic truths which they, and only they, are capable of understanding. They must hide this knowledge from the generality of people, i.e., the masses, and they may reveal it only to the chosen few, whose intellectual ability and philosophic training enable them to understand it. With other Islamic philosophers, Averroes shared the vision of an ideal state ruled by philosophers (patterned after Plato's Republic). However, unlike them, he does not expect that political revolution will bring this state into being in the near future, though he does not altogether exclude the possibility that a succession of enlightened rulers may bring it about. The absence of the ideal state in the present does not bring Averroes to Ibn Bājja's (*Avempace) position that the philosopher should live as a solitary stranger within the community in which he finds himself. Instead Averroes advocates that the philosopher should live within the state as an integral part, working for its welfare. At the same time, the philosopher must pursue his philosophic studies by himself or with likeminded people, but not propagate philosophy, since the public teaching of philosophy destroys the community. In his commentaries Averroes endeavors to grasp the intentions and conceptions of Aristotle, whom he calls "the perfect man." As part of his exposition he polemicizes against *Avicenna who, according to his view, had compromised some Aristotelian teachings by capitulating to theological concerns. Averroes sometimes resorts to philological methods to establish the text on which he comments and, not knowing Greek, he compares the Arabic versions. While a number of Averroes' interpretations deal with fine points of Aristotelian philosophy, there are major doctrines which serve to determine his position. Thus he objects to Avicenna's view that essence and existence are ontologically distinct, that is to say, that existence is an accident superadded to essence, holding instead that they are merely analytic distinctions within individual substances. Differing once again with Avicenna who considers God an intelligence apart from the world, Averroes inclines to identify God with the mover of the first celestial sphere. Whereas for Avicenna the essential attributes of God must be understood negatively, for Averroes they have a positive meaning. Considering the origin of the world, Averroes rejects the Neoplatonic doctrine of emanation, holding instead that the world is eternal. In psychology Averroes changed his views over time, but his final position on the intellect seems to be a doctrine of the unity of the material intellect in all human beings, from which it follows that human immortality is collective rather than individual. All in all, while Avicenna's interpretation of Aristotle had a certain theological bent, Averroes' was more naturalistic. While Averroes had little influence on Islamic thought, Latin and Hebrew translations of his works made him a central figure in Christian and Jewish philosophy from the 13th century on.

Role in Jewish Philosophy

In late medieval Jewish philosophy, Averroes became, next to Maimonides, the most important influence. He arrived at this stature as a result of Maimonides' high recommendation of him and by means of the many Hebrew translations of his works, especially of the commentaries. Jewish philosophers describe him by such appellations as "the great sage," "the chief of the commentators [on Aristotle]," and "the soul and the intellect of Aristotle." Among Jewish philosophers (as among Christians) there were some who tried to harmonize Averroes' teachings with those of Judaism, while there were others who had a purely philosophic interest in his views. Since Maimonides and Averroes disagreed on certain philosophic topics, some Jewish philosophers also attempted to reconcile their divergent views. Nearly all of Averroes' commentaries and independent works were translated into Hebrew, many of them more than once, but most of these translations exist at present only in manuscript form. Critical editions of the Arabic, Hebrew, and Latin versions of Averroes' commentaries, as well as modern translations of them, have appeared under the collective title Corpus Commentariorum Averrois in Aristotelem (see H.A. Wolfson, in: Speculum, 6 (1931) and 37 (1963), and G. Endress, "Averrois Opera," in: Endress and Aertsen, Averroes and the Aristotelian Tradition (1999)).

Hebrew Translations of His Works

The range of the translations of the commentaries may be gathered from the following partial list: Jacob b. Abba Mari *Anatoli translated in 1232 the middle commentary on Porphyry's Isagoge and those on the first four books of Aristotle's Organon; Moses b. Samuel ibn *Tibbon translated between 1244 and 1258 almost all of the epitomes of Aristotle's works on natural science and metaphysics, and in 1261 the middle commentary on the De Anima; Zerahiah b. Shealtiel Hen (*Gracian) translated in 1284 the middle commentaries on the Physics and the Metaphysics; Jacob b. Machir translated in 1289 the epitome of the Organon, and in 1302 the epitome of part of the De Animalibus; Kalonymus b. Kalonymus of Arles translated between 1313 and 1317 the middle commentaries on the Topics, Sophistical Refutations, Physics, On Generation and Corruption, Meteorology, and Metaphysics, as well as the long commentaries on the Posterior Analytics and, it seems, the Physics and Metaphysics; Samuel b. Judah of Marseilles translated in 1320–22 the middle commentary on the Nicomachean Ethics and the commentary on Plato's Republic; Todros Todrosi of Arles translated in 1337 the middle commentaries on the Rhetoric and Poetics.

In addition to the commentaries on Aristotle, Averroes' independent works were also translated into Hebrew. The Tahāfut al-Tahāfut was translated twice: once under the title Happalat ha-Happalah by *Kalonymus b. David b. Todros, who completed his translation in 1328; a second time anonymously under the title Sefer ha-Tekumah. The anonymous translation was used by *Moses b. Joshua of Narbonne. There also exist medieval Hebrew translations of the Fasl al-Maqāl (the treatise on the connection between religion and philosophy); of logical, physical, and metaphysical questions; the treatises on the conjunction of the hylic and the active intellects, and the De Substantia Orbis. The Hebrew translations of Averroes' commentaries, in turn, gave rise to supercommentaries on these works. The most famous of the authors of the supercommentaries was *Levi b. Gershom (Gersonides) (see R. Glasner, in: jqr, 86 (1995), 51 ff.). Other commentators on the commentaries by Averroes include *Jedaiah ha-Penini, Solomon of Urgul, R.S. ha-Levi, Isaac Albalag, Judah b. Isaac ha-Kohen of Provence (second half of the 14th century), Moses of Narbonne, Joseph *Kaspi, Abraham *Avigdor, Mordecai Natan, Abraham *Bibago, Isaac *Ibn Shem Tov, Shem Tov ben Joseph *Ibn Shem Tov, *Judah b. Jehiel (Messer Leon), Eli Habillo, and Elijah *Delmedigo. In addition, Levi b. Gershom, Moses of Narbonne, Joseph *Ibn Shem Tov, and Elijah Delmedigo also wrote commentaries on some of Averroes' original works.

Influence on Jewish Philosophy

Since Averroes and Maimonides were both born in Cordova, some historians (for example, Leo Africanus) assumed that the two were close to one another; it has even been maintained that Maimonides was a pupil of Averroes. Some have found Averroes' views in the Guide (for example, Isaac Abrabanel in his commentary on Guide 1:51). However, all of these conjectures are incorrect, for, while some of Maimonides' views appear to be similar to those of Averroes, it seems certain that Maimonides was not familiar with Averroes' commentaries when he wrote the Guide (S. Pines (trans.), Guide of the Perplexed (1963), cviii–cxxiii; H.A. Wolfson, Crescas' Critique of Aristotle (1929), 323). Maimonides mentions Averroes' works in two letters. In 1190, when Maimonides had completed at least some portions of the Guide, he wrote to his pupil Joseph b. Judah Ibn Shem Tov that he had received only recently Averroes' commentaries with the exception of the one on De sensu et sensato. He also wrote that, while he had not had time to study them carefully, he was favorably impressed by their content (Iggerot ha-Rambam, ed. I. Shailat (1995), i, 299, 313). Similarly, in a letter to Samuel ibn Tibbon, the translator of the Guide, in 1199, Maimonides strongly recommends the commentaries of Averroes as an aid for understanding Aristotle (ibid., ii, 552–53). As a result perhaps of Maimonides' high praise for Averroes' commentaries, they became in Hebrew translation the prime source for studying Aristotelian science, supplanting even the works of the Stagirite himself. Among the philosophers of the 13th and 14th centuries, Levi b. Gershom and Moses of Narbonne are usually considered faithful followers of Averroes. However, this applies only to Moses of Narbonne, whose commentary on Maimonides' Guide is pervaded by Averroes' ideas (see esp. on 1:68 and 1:70), not to Gersonides. While the latter accepts a number of Averroes' teachings, e.g., the eternity of the world (but only partially); that the existence of a thing is identical with its essence, not something superadded to it; that God can be described through positive attributes; he differs from him on a number of others (Milhamot Adonai, passim). R. Glasner has shown in several studies that in his supercommentaries on Averroes' epitomes and middle commentaries on Aristotle's books on natural science, Gersonides rejects certain fundamental Aristotelian positions presented therein, such as the Aristotelian accounts of natural motion and violent motion (see, e.g., Glasner, in C. Sirat et al. (eds.), Les méthodes de travail de Gersonide (2003), 90–103, esp. 98–101). Averroes' commentaries served as the principle source for the first two 13th-century encyclopedias of science and philosophy, the Midrash ha-Ḥokhmah by Judah b. Solomon ha-Kohen ibn *Matkah and the De'ot ha-Filosofim (ascribed incorrectly in the manuscripts to Samuel ibn Tibbon) by Shem Tov b. Joseph ibn *Falaquera. While the Midrash ha-Ḥokhmah presents a much abridged version of Averroes' commentaries, the De'ot ha-Filosofim quotes them at length, often blending sections of the various commentaries together for the sake of clarification and comprehensiveness. Falaquera explains his reliance on Averroes in his introduction where he states: "All that I write are the words of Aristotle as explained in the commentaries of the scholar Averroes, for he was the last of the commentators and he incorporated what was best from the [earlier] commentaries." This view of Averroes is explicitly shared by another 13th-century encyclopedist, Levi ben Hayyim of Villefranche, who writes that "the books of Aristotle are better than the books of anyone else" and the "commentaries of Averroes are superior to all other commentaries." Falaquera in another work, his commentary on Maimonides' Guide, writes that Averroes "inclines toward the views of our sages" (Moreh ha-Moreh, ed., Y. Shiffman (2001), intro., 116), and he cites him in his commentary over 80 times. In his Iggeret ha-Vikku'aḥ, he bases his own attempt to harmonize philosophy and religion on that of Averroes' Fasl al-Maqāl. Gershom b. *Solomon, the author of the popular late 13th-century encyclopedia, Sha'ar ha-Shamayim, also cites many of Averroes' views, although he generally does not incorporate his commentaries on Aristotle. Other philosophers influenced by Averroes include Isaac Albalag, Jedaiah ha-Penini, Joseph Kaspi, Nissim of Marseilles, and Moses ben Judah Nogah. *Hillel b. Samuel of Verona in his Tagmulei ha-Nefesh follows Averroes in teaching that there exists only one universal soul (1:5) and that the human intellect is ultimately united with the cosmic active intellect (1:6), but, contrary to Averroes, he holds that the human intellect is part of the individual human soul and that it is subject to reward and punishment in the hereafter (2). Many of Averroes' opinions are also cited by the 14th-century Karaite philosopher *Aaron b.*Elijah in his Eẓ Ḥayyim, though this philosopher opposes Averroes on the whole. Ḥasdai *Crescas was very familiar with Averroes' commentaries, in particular those on Aristotle's natural science, and relies on them for his knowledge of Aristotelian science. While a severe opponent and learned critic of Averroes, he accepts his view that God can be described by means of positive attributes, a view also accepted by Abraham *Shalom in his Neveh Shalom. During the late Middle Ages, which saw the gradual decline of Jewish philosophy, there still existed Jewish philosophers who studied Averroes and followed his teachings. Simeon *Duran uses Averroes' treatises on philosophy and religion in his Keshet u-Magen (directed against Islam), while he attacks his system in his Magen Avot. Even Averroes' opponents accepted his views on theologically neutral topics, which were not in conflict with religious teachings, for example in logic, or in instances in which his views supported Jewish teachings. Judah b. Jehiel (Messer Leon), who commented on Averroes' logic, also followed him in his Mikhlal Yofi, a compendium on logic. Obadiah *Sforno, who in his Or Ammim defends Jewish tradition against Aristotle (interpreted according to Averroes), accepts some of Averroes' views concerning God's knowledge and will, as set down in his Tahāfut al-Tahāfut. Joseph b. Shem Tov, who composed commentaries on Averroes' treatises on the material intellect and on conjunction, cites, in his Kevod Elohim, many of Averroes' views even though, in general, he is against philosophy and the "stubborn" Averroes. The last important Jewish Averroist was Elijah Delmedigo, who, in 1482, composed a work concerning the intellect and prophecy according to the teachings of Averroes and who used Averroes' Fasl al-Maqāl in his treatise on faith and reason, Beḥinat ha-Dat. Elijah was a faithful student of Averroes and was very familiar with Averroes' philosophic works, some of which he translated into Latin, some of which he commented upon, and many of which he used in his independent treatises on psychology, metaphysics, and especially natural science. In the 15th century when Jewish thought assumed a more conservative theological character, Jewish thinkers gradually moved away from the radical theological teachings of Averroes. Thus Isaac *Abrabanel, who at times bases himself on Averroes in his commentary on Maimonides' Guide, polemicizes against him in his Shamayim Hadashim and in other works. Similarly Abraham *Bibago, who wrote commentaries on several of Averroes' writings, including one on Averroes' middle commentary on the Metaphysics (in which he also refers to Averroes' short and long commentaries), attacks him in his Derekh Emunah. For a variety of reasons Averroes' scientific commentaries also became less popular, although, as is evident also from the many Hebrew copies of them written in the 16th century, they continued to be studied. However, by the mid-16th century, their impact seems to have become minimal.

Medical Writings

Among Averroes' medical works, the most important is Kitāb al-Kullīyāt fī al-Tibb, a seven-book summary of the medicine of his day. This work was translated into Latin under the title Colliget in 1255 in Padua by Jacob Bonacosa, and was printed many times (1490, 1496, 1497, 1514, 1531, and 1533). Jacob *Mantino translated the fifth book of the Kullīyāt (on special drugs) into Latin. This translation was made from the first (?) Hebrew translation and also printed a number of times. On Averroes' approach to pharmacology, as expressed in the fifth book of the Kullīyāt, and the contexts through which his famous medical work should be understood, see T. Langermann's suggestive study, "Another Andalusian Revolt?" (in: J.P. Hogendijk and A.I. Sabra, The Enterprise of Science in Islam (2003)).

There are two Hebrew translations of the Kullīyāt extant in manuscript. The first one, by Solomon b. Abraham ibn Daud (beginning of 14th century), is called Mikhlal (Bodleian Library, Ms. Opp. 176; Paris, Ms. Heb. 1172). Another copy was found by S. Muntner (Rome, Bibl. Casenateanse, Ms. 2762; also Ms. Jerusalem). The second translation, at one time thought to be an anonymous one, was apparently made by *Jacob ha-Katan in Provence as is evident from the separate use of medical terms in Provençal and Hebrew.

Averroes' Kullīyāt is mentioned by a number of Jewish authors. Shem Tov b. Joseph ibn Falaquera cites the work and praises it as follows: "The Kullīyāt is small and good and has no impurities, and all its words are true and of much use." Gershom b. Solomon mentions the work in his encyclopedia, Sha'ar ha-Shamayim. Samuel ibn *Zarza, who lived in the 14th century, refers to the Kullīyāt in his philosophical commentary on the Pentateuch and, a century later, Abraham Bibago mentions that he had composed a commentary on the Kullīyāt, but this is lost. Isaac Abrabanel writes in his commentary on the Bible (Lev. 15, beginning), when speaking of the three digestive systems in the living body: "… and the third digestion is in the organs and that is the true opinion as written by Averroes in the book al-Kullīyāt and not as written by Maimonides that the third digestion is in the openings of the veins and the fourth digestion is the organs." In addition to the Kullīyāt, there are Hebrew translations of other medical works of Averroes, among them that of Moses ibn Tibbon of Averroes' commentary on the Urjūza of Avicenna.


E. Renan, Averroès et l'averroïsme (1852, 1861, and many reprints and republications); Munk, Mélanges, 418–58, 461–511; Steinschneider, Hebr. Uebersetzungen, index; Baer, Spain, index; E. Gilson, History of Christian Philosophy in the Middle Ages (1955). add. bibliography: G. Endress and J.A. Aertsen (eds.), Averroes and the Aristotelian Tradition (1999); M. Cruz Hernández, Averroes: Vida, obra, pensamiento, influencia (1986, 19972); R.C. Taylor, in: P. Adamson and Taylor (eds.), Cambridge Companion to Arabic Philosophy (2005); A. Hasnaoui (ed.), La pensée philosophique et scientifique d'Averroès dans son temps (2005); Multiple Averroès (1978); S. Harvey, in: jsq, 7 (2000); D.H. Frank and O. Leaman (eds.), Cambridge Companion to Medieval Jewish Philosophy (2003), index; G. Tamari and M. Zonta, Aristoteles Hebraicus (1997); S. Harvey (ed.), The Medieval Hebrew Encyclopedias of Science and Philosophy (2000); M.C. Vázquez de Benito, Obra médica Averroes (1998).

[Shlomo Pines,

Bernard Suler, and

Suessmann Muntner /

Steven Harvey (2nd ed.)]

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