Al-Fārābī’s title of ‘‘Second Teacher’’ after Aristotle is well-warranted. Al-Fārābī’s work serves to illuminate the writings of the ‘‘First Teacher’’ in interesting and overlooked ways that go beyond the parameters of Aristotelian logic. Credence is lent to this assessment through the analysis of a specific topic, namely, authentic prophetic vision. At first glance, this seems like a strange assertion to make given Aristotle’s apparent skepticism and indifference regarding the topic of prophecy. However, as this paper will show, there is a latent theory of prophetic vision in the extant texts of Aristotle that al-Fārābī recognizes and completes in a way that is, in large part, faithful to and consistent with the corpus of Aristotle as we read it today. In the end, al-Fārābī provides insight into how a properly Aristotelian theory of authentic prophetic vision could be realized.

After he wrote his well-known De aspectus, al-Kindī wrote a substantial critical commentary on Euclid's Optics: the “Rectification of error and difficulties due to Euclid's book: the Optics.” This previously ignored work enriches our knowledge of the optics not only of the geometers of the mid-9th century, but also of late antiquity. This is the first known commentary on Euclid's treatise, and it raises again the questions of its textual traditions, their multiplicity, and the role of Theon of Alexandria; it also poses the problem of the survival of al-Kindī's thought through his successors, such as Ahmad b. 'Īsā. The article examines these and related issues.

Euclid discusses the ex aequali relationship twice in the Elements. The first is in Book V (based on definitions 17 and 18, propositions 22 and 23), during his discussion of arithmetical relations between mathematical magnitudes in general. The second is in Books VII–IX (developed using proposition VII,14), where he focuses on arithmetical relations in the case of numbers only. Although the distinction between mathematical magnitudes in general and numbers in particular often seems somewhat forced to contemporary philosophers, it was apparently very real to Euclid. Because Euclid seemed so conscious of the differences between the subject matter of Book V (magnitudes) and Books VII–IX (numbers), he was not much troubled by the differences between his treatment of ex aequali ratios in these two contexts. Later generations of mathematicians, however, found these differences less acceptable and tried to minimize them in various ways. This paper summarizes Euclid's use of the ex aequali relation in developing his mathematics. The paper then outlines the fate of the post-Theonine Greek attempts to “improve” the Euclidean discussion when the Elements entered the Arabic/Islamic intellectual tradition. The study concludes with the attempts by Ibn al-Hayṯam and Ibn al-Sarī to improve the parallelism between the discussions of ex aequali ratios in Book V and Book VII.

This paper shows for the first time that Maimonides significantly relied on Avicenna's “Refutation of astrology” (Al-Išāra ilā fasād ῾ilm aḥkām al-nujūm) when composing his own refutation, the “Epistle on astrology” (῾Al Gezērat ha-kōkhabīm). Maimonides consulted a copy of Avicenna's Refutation, partially using its structure as a model for his Epistle, and adapting some of its arguments. Therefore, it may be said with certainty that Maimonides carefully read at least one of Avicenna's works, and that his Epistle is not based solely on his own previous works, the “Commentary on the Mishnah”, the “Code of Jewish law”, and the “Guide of the perplexed”.

Alongside his much-discussed theory that humans are permanently, if only tacitly, self-aware, Avicenna proposed that in actively conscious self-knowers the subject and object of thought are identical. He applies to both humans and God the slogan that the self-knower is “intellect, intellecting, and object of intellection (‘aql, ‘āqil, ma‘qūl)”. This paper examines reactions to this idea in the Islamic East from the 12th-13th centuries. A wide range of philosophers such as Abū l-Barakāt al-Baghdādī, Faḫr al-Dīn al-Rāzī, al-Šahrastānī, Šaraf al-Dīn al-Mas‘ūdī, al-Abharī, al-Āmidī, and Naṣīr al-Dīn al-Ṭūsī raised and countered objections to Avicenna's position. One central problem was that on widely accepted definitions of knowledge – according to which knowledge is representational or consists in a relation – it seems impossible for the subject and object of knowledge to be the same. Responses to this difficulty included the idea that a self-knower is “present” to itself, or that here subject and object are different only in “aspect (i‘tibār)”.

The extant manuscript tradition of the Kitāb al-Kašf provides evidences of three phases of redaction and revision of the treatise. This study aims to illustrate the relations between the two Arabic versions and the anonymous fourteenth century Hebrew translation, taking into account the additions and modifications that differentiate them. I conclude that the Hebrew translation represents an intermediate stage of reworking, attesting important additions to the text as well as philosophical changes, especially in arguments concerning the creation of the world at the beginning of the treatise. However, it precedes the next revision phase of the text, which leaded to the modifications of the last Arabic version, in the chapters dealing with the thorny questions of divine corporeality and direction. The analysis of additions and arguments in the matter of content, context and reasoning helps to understand the redaction phases' history and the way the treatise was transmitted.

The Andalusian mathematician and astronomer Ibn Muʿāḏ al-Jayyānī (11th century) is the author of an important commentary on the concept of ratio, in which he attempts to justify the Euclidean definition of proportionality between magnitudes – the celebrated Definition V.5 – and that of greater ratio. In addition to an analysis of the commentary, we provide a French translation and a critical edition of the original Arabic text. We also attempted to settle some problems linked to the biography of Ibn Muʿāḏ.

Le présent article revient sur la polémique entre Abū Bakr al-Rāzī et Abū al-Qāsim al-Balḫī. En s'appuyant sur le témoignage du Kitāb taṯbīt dalāʾil al-nubuwwa du Qāḍī ʿAbd al-Ǧabbār, on montre que les deux philosophes ont dû s'affronter à la cour d'Aḥmad b. Sahl al-Marwazī, gouverneur de Balḫ, durant les années 910, et que la virulence du ton de leur échange s'explique surtout par ce contexte de rivalité professionnelle. Pour ce qui est de son contenu, leur entretien a dû porter sur la question de la justice divine et sur la meilleure manière de rendre compte de la prophétie et du message coranique. Dans un second temps, on passe à l’étude du chap. VIII, 4 de Al-maṭālib al-ʿāliya de Faḫr al-Dīn al-Rāzī et l'on montre que, contrairement à une opinion récemment émise, ce chapitre constitue un écho non pas d'Abū Bakr al-Rāzī, mais du premier argument du Kitāb al-zumurrud d'Ibn al-Rāwandī, qui opposait l'autonomie de la raison à la nécessité de la prophétie pour conclure de la première à la négation de la seconde. On suggère pour finir que la doctrine de la prophétie d'Abū Bakr al-Rāzī, comme celle des grands théologiens de son temps, tant muʿtazilites qu'ašʿarites, vise à échapper au dilemme mis en place par Ibn al-Rāwandī quelques décennies plus tôt.

Both Arabic modernists and Western humanists often regard the Muslim philosopher Averroes as one of the earliest precursors of Kant and the European Enlightenment. In contrast to this reputation, this paper argues that it was Kant’s critics Herder and Tiedemann who rediscovered Averroes. Tiedemann was the first German historiographer to give an accurate account of Averroes’ thought. This was accompanied by a re-evaluation of Averroes by Herder in his Letters for the Advancement of Humanity, in which he recognized the similarity between his own concept of the spirit of the age as historical reason – his alternative to the Enlightenment concept of a universal and ahistorical reason – and Averroes’ concept of a single material intellect for all individual human minds. Finally, the paper outlines the possible connections between Averroes’ interpretation of Aristotle’s intellect and Hegel’s concept of reason in history.

Dans sa description de l'œuvre en langue vulgaire de Lorenzo Ghiberti, Giorgio Vasari, quoiqu'il en dénigre certains aspects, saisit bien, nous semble-t-il, les traits marquants des Commentaires de Lorenzo, en particulier ceux du troisième livre concernant l'optique: Scrisse Lorenzo un'opera in volgare nella quale trattò di molte cose, ma sì fattamente che poco costrutto se ne cava… [que l'on en tire très peu de connaissances utiles…] Né tacerò che egli mostra il libro essere stato fatto da altri [Je ne tairai pas qu'il montre que le livre a été fait par d'autres personnes]

Late in his intellectual life, Faḫr al-Dīn al-Rāzī espoused a dualistic position on the nature of the soul, denying that the soul is in any sense a material body. This view, which in broad terms concurs with Avicenna’s, sets al-Rāzī in opposition to the theologians’ materialistic stance. To make his position clear, in his last work Almaṭālib al-Rāzī sets out a comprehensive case for the theologians’ materialism, before critiquing that position. This paper offers a reconstruction of al-Rāzī’s arguments for the theologians’ materialism, providing an insight into arguments in the philosophy of mind during the Islamic Middle Ages.

Muhsin Sayyid Mahdi, James Richard Jewett Emeritus Professor of Arabic at Harvard University, died on July 9 inBrookline, Massachusetts, after a long series of illnesses.

The only traces which remain of Abū Sahl al-Qūhī's work on centers of gravity are the correspondence he maintained with Abū Is[hdotu]āq al-[Sdotu]ābi', and the first chapter of the Kitāb Mīzān al-[hdotu]ikma, which 'Abd al-Ra[hdotu]mān al-Khāzinī attributes to al-Qūhī and to Ibn al-Haytham, without distinguishing between their respective contributions. The author of the present article attempts to confront the texts and to analyse all the testimonies which have come down to us on this subject, which are susceptible of shedding light upon al-Qūhī's contribution and the importance of his work on centers of gravity.

During the second half of the twentieth century an attention of historians of mathematics shifted to mathematics of the Late Antiquity and its subsequent development by mathematicians of the Arabic world. Many critical editions of works of mathematicians of the Hellenistic era have made their appearance, giving rise to a new, more detailed historical picture. Among these are the critical editions of the works of Diophantus, Apollonius, Archimedes, Pappus, Diocles, and others.

Coming after Muʾayyad al-Dīn al-ʿUrḍī (1200–1266) and Naṣīr al-Dīn al-Ṭūsī (1201–1274), Quṭb al-Dīn al-Shīrāzī (1236–1311), a leading figure of the so-called Marāgha school in astronomy, presents his predecessors’ non-Ptolemaic models and criticizes them in his three hayʾa books. Since his own new models in Nihāyat al-idrāk (written in Arabic in 1281) and Ikhtiyārāt muẓaffarī (written in Persian in 1282) are not without difficulties, in his latest book on hayʾa, al-Tuḥfa al-shāhiyya (written in Arabic in 1285) he puts forward his modified models inspired from Ṭūsī’s and ʿUrḍī’s models and produces a series of new models for Mercury and the oscillation of the spheres. Nevertheless, in spite of all his attempts, the tradition of non-Ptolemaic modeling after him never converged to a series of standard models.

Galen's Technê iatrikê (Tegni, for short) was translated into Hebrew three times. The first two translations were executed in the Midi, around the year 1199: once from Constantine the African's Latin version, by an anonymous physician who used the pseudonym “Doeg the Edomite”; and a second time from Arabic, by Samuel Ibn Tibbon in Béziers, using as his Vorlage Ḥunayn Ibn Isḥāq's Arabic version (al-Ṣināʿa al-saġīra), accompanied by ʿAlī Ibn Riḍwān's commentary. (Samuel Ibn Tibbon's authorship of this translation has been called into doubt, but is reestablished in a paper by Gad Freudenthal in this issue of ASP.) A third translation, again from Latin and including Ibn Riḍwān's commentary, was done by Hillel ben Samuel in Rome, in the late thirteenth century, but is not considered in this paper.

We present the Tegni and discuss its history. We then ask why this work was translated into Hebrew twice, at precisely the same time and area. We show that both translators responded to the need of Jewish physicians who read only Hebrew. Doeg's translation was part of his vast project of making the greater part of the Salernitan corpus available in Hebrew. Samuel Ibn Tibbon translated the Tegni with Ibn Riḍwān's commentary both because he was responding to a social need and because he was in the process of switching his profession from physician to translator of philosophic works. Galen's medico-philosophic text was a perfect fit for his intellectual evolution from a philosophically minded physician to a philosopher-scientist.

The present article aims to provide a reconstruction of the interpretation offered by Thomas Aquinas of the cognitive process described at the beginning of Aristotle's Physics and of his criticism of Averroes' interpretation. It expounds to this end the exegesis of ancient Greek commentators who opened the debate on this question; then, it puts forward a reconstruction of Aquinas' doctrine by means of other texts of his corpus, as well as an explanation of his criticism of Averroes' exegesis; it finally reconstructs Averroes' interpretation worked out in his Great Commentary to Phys. I, 1, in order to show that Aquinas' disapproval is partly due to an incorrect interpretation of Averroes' divisio textus of Phys. I, 1. It suggests as well that, concerning some fundamental points, Aquinas' exegesis doesn't diverge from the interpretation proposed by Averroes.

Né le 4 février 1917 dans un village des environs de Damiette, ‘Abd al-Rahmān Badaī s'est éteint au Caire, où il avait étudié puis enseigné – à l'Universitél – avant de joindre l'Université d'Héliopoplis. ‘A. Badawī nous laisse une oeuvre monumentale, plus de cent-vingt livres en arabe et cinq autres en français. Mondialement connu, son impact sur l'histoire de la philosophie grecque, sur l'histoire de la philosophie islamique et sur la pensée arabe au cours de la seconde moitié du XXe siècle, est immense et incontestable. Travailleur solitaire et acharné, il n'a jamais été égalé pour ses connaissances tant linguistiques que philosophiques et historiques, et surtout pour l'étendue des champs du savoir qu'il a pu couvrir.

This article analyses Avicenna's Ḥayawān III, 1, which deals with the well-known disagreement between physicians and philosophers on the origination of blood vessels (arteries and veins) and nerves. However, the proposed analysis is not limited to this chapter and its main topic. The more general purpose of this article is to reconstruct the psycho-medical context in which Avicenna's exposition lies, that is, the soul's oneness and the consequent conditions for body ensoulment (i. e. the soul's need for a primary, unitary attachment to the body through the heart and the cardiac pneuma). The article then outlines the strategy through which Avicenna presents medical positions (heart, brain, and liver are all on an equal footing) that challenge his (and Aristotle's) anatomical model, which is coherent with his theory of the soul. In this connection, firstly, the article shows how Avicenna takes physicians’ arguments apart in a philosophical context (he usually points at their logical shortcomings). Then, it clarifies the contribution of anatomy to determine the conditions of body ensoulment and, ultimately, how to reconcile medical practice with philosophical truths, if need be.

This study consists in a commentary on some passages from Avicenna, which deal with the category of the relative. The commentary points out the promotion of the relative to the role of an exclusive determining factor. An attempt is made here to show how Avicenna tries to detach the relative accident from its subject, in order to transform it into the exclusive determining factor of a pure thingness. The relative determination of this thingness must be able to receive specifications, which may extend as far as the infimae species. These specifications are obtained by the consideration of the other attributes of the subject of the relative attribution, which are henceforth no more than the “modes of advent” of the relation.