* I would like to thank Charles Butterworth for his careful and patient editing of my manuscript, and Ahmed Hasnaoui for his valuable suggestions and corrections.
1 Averroes, , Commentarium Magnum in Aristotelis De Anima Libros, ed. Crawford, F. Stuart, Corpus Commentariorum Averrois in Aristotelem, Latin version VI 1 (Cambridge, 1953), III, comm. 14, p. 433.
2 See Moraux, Paul (ed. and trans.), Aristote, Du ciel (Paris, 1965), p. vii.
3 See Flashar, Helmut, Die Philosophie der Antike, 3: Ältere Akademie, Aristoteles, Peripatos, Grundriss der Geschichte der Phiosophie (Basel, 1983), pp. 265 ff. and 314;Elders, Leo, Aristotle's Cosmology: A Commentary on the De Caelo, Philosophical Texts and Studies 13 (Assen, 1966), pp. 59 ff.; and Moraux, Paul, “Einige Bemerkungen über den Aufbau von Aristoteles' Schrift De Caelo,” Museum Helveticum, 6 (1949): 157–65, “Recherches sur le De Caelo d'Aristote,” Revue Thomiste, 51 (1951): 113–36, and Du ciel, pp. cvi–cxxvi.
4 See Effe, Bernd, Studien zur Kosmologie und Theologie der aristotelischen Schrift “Über die Philosophie”, Zetemata 50 (Munich, 1970), pp. 20–3.
5 See Elders, Aristotle's Cosmology, p. 27.
6 See Elders, Aristotle's Cosmology, p. 29.
7 See Moraux, Du ciel, pp. xliv–xlv and the references to the early and modern discussions of this point.
8 See Easterling, H. J., “Homocentric spheres in De Caelo,” Phronesis, 6 (1961): 141–5.
9 See Moraux, Paul, “Quinta Essentia,” in Paulys Realencyclopaedie der Classischen Altertumswissenschaft, 47/XXIV 1 (1963), columns 1171–1263, and Du ciel, pp. li ff.
10 Phaedrus 245C; see Elders, Aristotle's Cosmology, pp. 27 and 30.
11 See Moraux, Du ciel, p. xlv and note 1 for references to the commentators who discuss this apparent contradiction.
12 For this development and the references in Aristotle's text, see Elders, Aristotle's Cosmology, pp. 27–33. I have followed Elders closely in the preceding summary of Aristotle's doctrine. See also, below, Sections 8 and 12.
13 See Elders, Aristotle's Cosmology, pp. 94–7.
14 Unless otherwise noted, the translations of De Caelo are taken from Stocks, J. L., De Caelo, The Works of Aristotle Translated into English 2 (Oxford, 1922).
15 See Moraux, Du ciel, p.xliv and note 5. But according to Alexander, as quoted by Simplicius, the whole passage would refer exclusively to the sphere of the fixed stars; see Simplicius, , In De Caelo, ed. Heiberg, I. L., in Aristotelis De Caelo commentaria, Commentaria in Aristotelem Graeca 7 (Berlin, 1894), 287:21 ff.
16 See Kitāb al-Samā' wa-al-'Ālam, in Aristūt;ālīs fi al-Samā' wa-al-Āthār al-'Ulwiyya, ed. 'Abd al-Rahmān Badawī (Cairo, 1961), 194:17–195:7; the quotation is revised on the basis of Averroes' Tafsīr Kitāb al-Samā' wa-al-'Alam, MS Tunis, al-Maktaba al-Wataniyya, collection al-Ahmadiyya 5538 (see my facsimile edition: Commentary on Aristotle's Book On the Heaven and the Universe by Ibn Rushd, Publications of the Institute for the History of Arabic-Islamic Sciences, series C, vol. 37 [Frankfurt am Main, 1994], p. 65, c. 100). Note ‘the spiritual’: al-shay' al-rūhānī; ‘the cause of all of the heaven's causes’: ‘lat kull d of Cremona and Michael Scot (confirmed by the Eastern tradition of the Arabic Aristotle and Averroes's comments), against 'illat kull 'illa min 'ālamihā of MS Tunis; ‘cognizable’: ma'lūma MS Tunis, ma'lūla in the other MSS.
17 See Simplicius, In De Caelo, p. 291; Guthrie, W. K. C., A History of Greek Philosophy (Cambridge, 1981), vol. 6, p. 261; and Elders, Aristotle's Cosmology, pp. 147–9.
18 See Averroes, , Talkhīs al-Samā' wa-al-'Ālam, ed. al-'Alawī, Jamāl al-Dīn (Fez, 1984), 141:13–142:7; henceforth Talkhīs.
19 The Arabic version has “the first mover,” al-muharrik al-awwal; see Kitāb al-Samā' wa-al-'Ālam, ed. Badawī, p. 250.
20 The Arabic version has “the first cause,” al-'illa al-ūlā.
21 Cf. Elders, Aristotle's Cosmology, p. 31 and Moraux, Du ciel, p. 164.
22 Easterling, “Homocentric spheres,” pp. 151–3.
23 For the Arabic terminology underlying Michael Scot's Latin version (demonstratio simpliciter, i. e., al-burhān al-mutlaq), see Rushd, Ibn, Tafsīr Mā Ba'd al-Tabī'a, ed. Bouyges, M., Bibliotheca Arabica Scholasticorum, série arabe, V, 1–2, VI, VII (Beirut, 1938–1952), 703:11. In his paper delivered at the Symposium Averroïcum II “Mulāhazāt fī tatawwur nazariyyat al-burhān 'inda Ibn Rushd” (forthcoming in Majallat Kulliyyat al-Ādāb wa-al-'Ulūm al-Insāniyya of the University Sidi Mohammed ben Abdallah, Fez), notes 19–27, Jamāl al-Dīn al-'Alawī examines the barāhīn mutlaqa at some length.
24 See Averroes, Commentarium Magnum in Aristotelis De Anima I, comm. 89, p. 119, and II, comm. 20, p. 159.
25 For the Latin text, see Averroes, , Commentarium Magnum in Aristotelis De Caelo, in Aristotelis Opera cum Averrois Cordubensis Commentariis (Venice, 1550).
26 See below, Sections 16 and 21; also Jamāl, al-Dīn al-'Alawī, “Ishkāl al-'alāqa bayn al-'ilm al-tabī'ī wa-mā ba'd al-tabī'a 'inda Ibn Rushd,” Majallat Kulliyyat al-Ādāb wa-al-'Ulūm al-Insāniyya, Special Issue 3 (1988): 7–51 and “Mulāahazāt,” Section 2.
27 Simplicius, In De Caelo, 397:5.
28 See Solmsen, F., “Platonic influences in Aristotle's physical system,” in Plato and Aristotle in the Mid-Fourth Century (Göteborg, 1960), p. 232, n. 2.
29 See Averroes, , [Jawāmi'] Kitāb al-Samā' wa-al-'Ālam in Rasā'il Ibn Rushd (Hyderabad, 1947), 42:18; henceforth Jawāmi'.
30 See Moraux, Du ciel, p. 157; and Elders, Aristotle's Cosmology, p. 134.
31 The same reference to Metaphysics XII.8 is quoted from Alexander by Simplicius, ad locum, In De Caelo 270:5–9: “In the Metaphysics he shows, according to Alexander, that the mover of the circular movement is one … if this is one, the body moved by it is also one, and if the body in circular movement is one, the cosmos is by necessity one.” But this interpretation was not available to Averroes through Themistius.
32 This is the very question posed by Alexander, apud Simplicium, In De Caelo 270:9; see Aphrodisiensis, Alexander, Maqāla fi Mabādi' al-Kull, in Aristū 'inda al-'Arab, ed. Badawī, 'Abd al-Rahmān (Cairo, 1947), 267:13–268:12.
33 See Simplicius, In De Caelo 270:14.
34 Ross, W. D., Aristotle's Metaphysics (Oxford, 1924), vol. 2, p. 384.
35 See Wolfson, H. A., “The plurality of immovable movers in Aristotle, Averroes, and St. Thomas,” Harvard Studies in Classical Philology, 63 (1958): 233–53; reprinted in Wolfson, , Studies in the History of Philosophy and Religion, ed. Twersky, I., Williams, G.H., 2 vols (Cambridge, Mass., 1973), vol. 1, pp. 1–21 (esp. pp. 10–11).
36 Cf. Talkhīs 237:15–17: law wujidat hādhihi al-haraka a'nī al-dawriyya fi kawkab wāhid la-lazima an tūjad fi jamī'ihā idh kānat tabī'atuhā wāhida bi-al-naw'.
37 Avicenna says, after presenting his emanationist cosmology, that the multiplicity inherent in the intermediate intelligences - attending the process of emanation - does not involve an identical series of multiple products caused by each: “Nor do these intelligences agree in [their] species.” See Kitāb al-Najāt (Cairo, 1938), 278:6, or ed. M. Taqī Dānishpazhūh (Teheran 1363/1985), 657:7; and al-Shifā', al-Ilāhiyyāt, ed. Anawati, G. C. and Zāyid, Sa'īd (Cairo, 1960), 407:7. Averroes sides with al-Fārābī here; see Mabādi' Ārā' Ahl al-Madīna al-Fā–ila, ed. Walzer, Richard as Al-Fārābī on the Perfect State (Oxford, 1985), 120:4 and commentary, p. 375.
38 See Averroes, , Tahāfut al-Tahāfut, ed. Bouyges, M., Bibliotheca Arabica Scholasticorum, Série Arabe, Vol. 3 (Beirut, 1930), 49:15–50:1; for the English translation, see van den Bergh, S., Averroes' Tahafut al-Tahafut (London, 1954), vol. 1, pp. 28–9.
39 This long commentary was written a decade after the Tahāfut al-Tahāfut. H. A. Wolfson's attempt to harmonize these statements seems inconclusive; see “The plurality of immovable movers,” vol. 1, pp. 15–16.
40 See Guthrie, , A History of Greek Philosophy, vol. 6, pp. 87 and 264 ff.; and Merlan, P., “Greek philosophy from Plato to Neoplatonism,” The Cambridge History of Later Greek and Early Medieval Philosophy (Cambridge, 1967), p. 41.
41 See Elders, Aristotle's Cosmology, p. 29.
42 Medieval discussions of this problem were first surveyed by Wolfson, H. A. in “The problem of the souls of the spheres from the Byzantine commentaries on Aristotle through the Arabs and St. Thomas to Kepler,” Dumbarton Oaks Papers, 16 (1962): 65–93; reprinted in Wolfson, Studies, vol. 1, pp. 22–59.
43 See Elders, Aristotle's Cosmology, pp. 179–82 and above, Section 3.
44 This translates 284a31, “it must therefore be without leisure [ascholon] and devoid of all rational satisfaction,” as mashghūla 'ādima li-kuli rāha kā 'ina min dhī 'aql, but it is not taken up in Ibn Rushd's Taikhāyat al-jahl wa-al-nasb (190:10). The criticism of the “plurality of gods” in the closing paragraph (191:3) is due to the Arabic version which converts the positive reference to popular religion (284b3) into a polemic against polytheism.
45 See also Talkhīs[Jawāmi'] <'Ilm> Mā Ba'd al-Tabī'a, IV.7. In the edition of Carlos, Quirós Rodríguez, Averroes, Compendio de Metafísica (Madrid, 1919), this corresponds to pp. 129–30; and in the edition of Amīn, 'Uthmān, Ibn Rushd, Talkhīs Mā Ba'd al-Tabī'a (Cairo, 1958), to p. 127.
46 See Maqāla fi Mabādī' al-Kull, p. 254. The harmonizing tendency in this work, especially in the closing passage, has led D. Gutas to doubt its authenticity: the “apologetic attitude” discerned here, “in all probability addressed to Christians,” would point “to a composition date of the treatise in late Alexandrian times,” Avicenna and the Aristotelian Tradition (Leiden, 1988), p. 217. Consider also the doubts expressed by Pines, Shlomo, “The spiritual force permeating the cosmos according to a passage in the Treatise on the Principles of the All ascribed to Alexander of Aphrodisias,” Studies in Arabic Versions of Greek Texts and in Medieval Science, The Collected Works of Shlomo Pines (Jerusalem, Leiden, 1986), vol. 2, pp. 252–5. Note that there is no corresponding passage in the excerpts from Alexander in Themistius' commentary on De Caelo, for it has a long lacuna at this place.
47 Simplicius, , In De Caelo 388:14–25, with reference to II.12.292a18: “for to act is proper to the rational soul in itself.”
48 Jawāmi' Mā Ba'd al-Tabī'a, 1V.22, Quiros, p. 137 and Amin, p. 134: “The planets have no other part of the soul than the one constituted by intellectual comprehension” (al-tasawwur al-aqlī, i. e., noēsis).
49 In the Arabic version of the Aristotelian text, as in Averroes' own expositions, the principle at work in the moving of desire toward the First Cause – thought [noēsis] – is called al-tasawwur bi-al-'aql. See Tafsīr Mā Ba'd al-Tabī'a, 1598:4 and ff., corresponding to Metaphysics XII.7.1077a30, and the passage cited next. The Jawāmi' Mā Ba'd al-Tabī'a was written shortly after the Jawāmi' al-Tabī'iyyāt; see Jamāl, al-Dīn al-'Alawī, al-Matn al-Rushdī: Madkhal li-qirā'jadīda (Casablanca, 1986), pp. 57–9.
50 See Maqāta fi Mabādi' al-Kull, 268:12–17 and 269:10–11. Cf. above, n. 46.
51 See Sīnā, Ibn, al-Shifā' al-Samā' wa-al-'Ālam, ed. Qāsim, Mahmūd (Cairo, 1969), pp. 33–4;al-Shifā al-Ilāhiyyāt, IX:2–3, pp. 381–401 (French translation, Anawati, Georges C., La Métaphysique du Shifā', Etudes musulmanes 27 [Paris, 1978–1985], pp. 119–36);Kitāb al-Najāt, Cairo, pp. 258–66, or ed. Dānishpazhūh, pp. 617–34; Dānishnāma-i Ālā'ī, Ilāhiyyāt, ed. Muhammad Mu'īn (Teheran, 1331/1952), Chaps. 51–53 (English translation, Morewedge, Parviz, The Metaphysics of Avicenna, A Critical Translation-Commentary, Persian Heritage Series, no. 13 [London, 1973], pp. 94–100). Cf. Wolfson, “The problem of the souls of the spheres,” pp. 41–5.
52 See also Jawāmi', p. 10: sa-nubayyin hādhā … fi al-falsafa al-ūlā … hāhunā innamā huwa 'alā jihat al-musādara 'alā mā tabayyana fi Kitāb al-burhān. See also, above, Sections 8 and 21. In addition, for a systematic presentation of the epistemological principles underlying this procedure - principles which ultimately go back to Aristotle's Posterior Analytics and to al-Fārabī's Kitāb al-Burhān - see al-'Alawī, “Mulāhaz;āt,” Section 2.
53 Avicenna, , Kitāb al-Najāt, Cairo, 241:8–10 or ed. Dānishpazhuh, , pp. 580: 14–581:4.
54 See Avicenna, , al-Shifā', al-Ilāhiyyāt, IX. 2, pp. 386–7 esp. 387:4–7.
55 That is, sōtērias charin; see Bonitz, Hermann, Index Aristotelicus (Berlin, 1870; Graz, 1955), art. sōtēria, for references.
56 See Averroes, , Tahāfut al-Tahāfut, 271:7–9: “The soul which is in the [celestial] body has no subsistence [qiwām] in this body. For this body is not in need of a soul, as are the bodies of animals, for the continuance of its existence.” See also Wolfson, “The problem of the souls of the spheres,” p. 43.
57 See Averroes' De Substantia Orbis, critical edition of the Hebrew text with English translation and commentary by Arthur Hyman, Corpus Philosophorum Medii Aevi, Opera Averrois (Cambridge, Mass, and Jerusalem, 1986).
58 De Substantia Orbis, III, lines 31–37; trans., pp. 102–3; see also pp. 32–5 and p. 113, n. 18 for Hyman's references to Tafsīr Mā Ba'd al-Tabī'a, XII, comm. 43 and 44, pp. 1644–5 and 1649–50.
59 See also De Substantia Orbis III, lines 42–49; trans., pp. 104–5 with an analogous reference to De Caelo I.12.
60 For this problem, relevant to De Caelo II.6, see also the Tafsīr II, comm. 38, fol 44a–b (quoted by al-'Alawī, Talkhīs, p. 226, n. 175).
61 For a very close parallel to the Talkhīs., pp. 179–82, see De Substantia Orbis, pp. 105–10. Davidson, Herbert A. provides a full exposition and source study of Averroes' discussions of this problem in the context of his critique of Avicenna's proof of the existence of a being necessarily existent by virtue of itself in “The principle that a finite body can contain only finite power,” Studies in Jewish Religious and Intellectual History Presented to Alexander Altmann (Huntsville, Alabama, 1979), pp. 70–80; see also Proofs for Eternity, Creation, and the Existence of God in Medieval Islamic and Jewish Philosophy (New York, 1987), pp. 321–31.
62 See Jawāmi' Mā Ba'd al-Tabī'a, IV,24, Quirós, pp. 138–9 and Amīn, p. 136; see also De Substantia Orbis, pp. 130–7.
63 See also Tafsīr Mā Ba'd al-Tabīa, 1078:2–3: sūra nafsāniyya 'aqliyya … mutanaffisa bi-dhātihā.
64 See Maqāla fi Mabādi' al-Kull, 256:8–10.
65 See Pines, Shlomo, “Omne quod movetur necesse est ab aliquo moveri: A refutation of Galen by Alexander of Aphrodisias and the theory of motion,” Isis, 52 (1960): 45–6; reprinted in Pines, Collected Works, p. 243.
66 This question is taken up in the Tafsīr on De Caelo 11.3, where Ibn Rushd refers (fol. 3b21) to a maqāla afradnāhā fi dhālika, i. e., to the first chapter of De Substantia Orbis.
67 See De Substantia Orbis, p. 105.
68 It is true that Avicenna would have known how to counter this criticism and, what is more, that Averroes did not have an adequate basis for judging Avicenna's doctrine and arguments. Apparently, much of what is relevant for his criticism was known to him only by way of al-Ghazālī's Tahāfut. See Davidson, Proofs for Eternity, Creation and the Existence of God, pp. 311–35, esp. p. 334: “Averroes' critique of the body of Avicenna's proof [sc. of the First Principle] is to an astonishing extent grounded in misinformation.” In the present context, we must nonetheless keep in mind that even though Ibn Rushd's criticism goes beyond physical theory, it touches upon a basic question of valid philosophical method.
69 See Simplicius, , In De Caelo, 488:18–24 and 492:25 ff. and Proclus, , Hypotyposis astronomicarum positionum, ed. Manitius, C. (Leipzig, 1909), p. 510.Cf. Cherniss, Harold, “The philosophical economy of the theory of ideas,” American Journal of Philology, 57 (1936): 445–56; reprinted in Cherniss, Selected Papers (Leiden, 1977), pp. 121–32. See also Samuel Sambursky, The Physical World of the Greeks (London, 1956), p. 59 and The Physical World of Late Antiquity (London, 1962); Mitteistrass, Jürgen, Die Rettung der Phānomene: Ursprung und Geschichte eines antiken Forschungsprinzips (Berlin, 1962).
70 For a critical edition of Michael Scot's Latin translation of al-Bitrūjī's text, see De motibus celorum, ed. Carmody, Francis J. (Berkeley and Los Angeles, 1952); and for an edition of the Arabic and Hebrew versions of al-Bitrī's Kitāb fi al-Hay'a with translation, analysis, and an Arabic-Hebrew-English glossary, see Goldstein, Bernard R., On the Principles of Astronomy (New Haven, 1971).
71 This is something he admitted; see Jawāmi' Mā Ba'd al-Tabī'a, IV.13, ed. Quirós, p. 133 and Amin, p. 130; see also below, Section 21.
72 See also the remarks on method outlined above at the end of Section 16.
73 See Easterling, “Homocentric spheres,” pp. 141 ff. and 152; also above, Section 8.
74 See Charles, Généquand, Ibn Rushd's Metaphysics: A Translation, with Introduction, of Ibn Rushd's Commentary on Aristotle's Metaphysics, Book Lām (Leiden, 1984), pp. 54 ff.
75 See also Henri, Hugonnard-Roche, “Remarques sur l'évolution doctrinale d'Averroès dans les commentaires au De caelo: le problème du mouvement de la terre,” Mélanges de la Casa de Velázquez, 13 (Madrid, 1977): 103–17.
76 See Hartner, Willy, Oriens - Occidens (Hildesheim, 1968), p. 461.
77 See, e.g., Commentarium Magnum De Caelo II, comm. 49, fol. 62ra23–26: “If diverse centers are assumed, impossible consequences will obtain, as we said; and in setting down eccentric [circles], the mathematicians did something that Aristotle did not at all say; but the reason given by him for the [apparent] variation is in the spiral motions [motus leulab]. On lawlab, see below, Section 22.
78 See Carmody, F., A1-Bitrūjī, tibus celorum and Innovations in Averroes De Caelo (Berkeley and Los Angeles, 1982).
79 Commentarium Magnum II, comm. 57, fol. 64ra35–43. See above, Section 16, at the end; also al-Färäbï, , al-Burhän, Kitäb, in al-Mant 'inda al-Färäbï, ed. Fakhrï, M. (Beirut, 1987), vol. 4, 25:11–26:14 and 66:13–17. Consider also Aristotle, Prior Analytics, I.30.46a17–22: “It falls to experience to provide the principles of any subject. In astronomy, for instance, it was astronomical experience that provided the principles of the science, for it was only when the phainomena were adequately grasped that the proofs in astronomy were discovered.” And see Owen, G. E. L., “’Tithenai ta Phainomena’” in Aristote et les problèmes de méthode, ed. Manison, S. (Louvain, 1961), pp. 83–103.
80 See Elders, Aristotle's Consmology, pp. 227 ff. and Moraux, Du ciel, pp. civ ff.
81 See “The Arabic version of Ptolemy's Planetary Hypotheses,”, ed. Goldstein, B. in Transactions of the American Philosphical Society, N. S., 57/4 (1967): 31 (correcsponding to fol. 90a3–6).
82 Ibid., pp. 27–9 (corresponding to folios 88b24–90a6). For the Arabic tradition, see Ibn, Sīnā, al-Shifā', 'Ilm al-Hay'a, ed. Mudawwar, Muhammad and Ahmad, Imām Ibrāhīm (Cairo, 1980), p. 463 (following Ptolemy); also Carmody, F., Al-Bitrūjī De motibus celorum, pp. 64–4 and 127–9 (but here Venus is above the sun and Mercury below).
83 We may compare this with Alexander, apud Simplicium, In De Caelo, 472:10 ff.: The planetary sphere is not moved unwillingly, but in accordance with its “purpose and desire” it may be necessity, but is also recognized as good.
84 Literally, moderni Arabes; see the passing mention in Commentarium Magnum II, comm. 67, fol. 67va56.
85 See Nallino, C. A., “Astrologia e astronomia pressi in Musulmanni,” Raccolta di scritti editi e inediti (Rome, 1939–1948). vol. 5, pp. 64–6 and 75;Bergh, S. vander, Averroes' Tahafut al-Tahafut, vol. 2, p. 24 (note 3 to vol. 1, p. 21); and Walzer, R., Al-Fārābī on the Perfect State, p. 364.
86 See Jawāmï Mā Ba 'd al-Tabï'a, IV. 15–16, Quirós, p. 134 and Amīn, pp. 131–2; see also van den Bergh's, S. German translation, Die Epitome der Metaphysik des Averroes (Leiden, 1924), pp. 112–13 and the comment on pp. 244–5.
87 See Commentarium Magnum II, comm. 62, fol. 66ra57.
88 See Genequand, Charles, Ibn Rushd's Metapysics, pp. 54 ff.
89 See Averroes, Tafsīr Mā Ba'd al-Tab'a XII, comm. 45 (on Metaphysics XII.8), pp. 1662–4; the translation is from Généquand, Ibn Rushd's Metaphysics, pp. 178ff. I have corrected Généquand's “Ptolemy was free from” (178:6) to read “Ptolemy failed to notice” see 1663:3 dhagaba 'alayhi.
90 See Endress, Gerhard, Die arabischen Übersetzungen von Aristoteles' Schirft De Caelo (Frankfurt am Main, 1966).
91 See al-'al-Alawī al-Matn al-Rushdī, pp. 55 ff.
92 See Henri, Hugonnard-Roche, “L'Epitomé De Caelo dˇAristote par Averroès: Questions de méthode et de doctrine,” Archives dˇhistorie doctrinale et littéraire du Moyen Age, année 49 (1984), vol. 51 (1985): 7–39.
93 See Steinschneider, Moritz, Die herbräiscehn Übersetzungen des Mittelaters und die Juden als Dolmetscher (Berlin, 1893; Graz, 1956), pp. 126 ff.
94 See al-'Alawī al-Matn al-Rushdī, pp. 55 ff.
95 See al-'Alwaī, al-Rushdī, p. 104.
96 On Averroes' treatment of the relevent topics in his commentaries on the Physics, see now Lettinck, Paul: Aristotle's Physics and Its Reception in the Arabic World (Lwiden, 1994), published after the completion of this article.