The authors translate and comment a digression from the Kitāb al-āṯār al-bāqiya on several hydraulic and hydrological subjects. The passage reveals al-Bīrūnī’s understanding of fluvial regimes, water physical behaviour, and of a handful of peculiar natural phenomena. Al-Bīrūnī departs from a discussion of weather forecast and seasonal fluvial regimes of the Tigris, Euphrates, Oxus, and Nile. The main concern of al-Bīrūnī is to defend the principle that water moves only downwards in absence of external forces. In doing so, the Khwarazmian scientist touches on the origin of salinity of the seas, the functioning of syphons related hydraulic machines, and relates a report of an artificial phenomenon, that he dismisses as result of faulty observations, that could be recognised as a hydraulic jump. In addition, the passage contains much relevant information on al-Bīrūnī’s understanding of the inhabitability of subequatorial regions, the possibility of the void, and the water cycle.

In this paper, we present the Aristotelian theory of comets, which is well known in the Muslim West through the commentaries of Ibn Rušd and Ibn Bāǧǧa. This aspect is covered three centuries later in an unknown manuscript attributed to the famous mathematician Ibn Ġāzī al-Miknāsī (1437-1513), and this text is not present in the known list of his works. The author devotes a part of his manuscript to the comet astrology following Ptolemy, and introduces a critical position of Iḫwān al-Ṣafā’, characterized by the rejection of the sidereal comets idea. We are also interested in comet classifications given by Ibn Ġāzī and another author ‘Alī al-Antākī. We found that the content of the De cometis of pseudo-Ptolemy is analogous with the text of Ibn Ġāzī, and almost identical to the text of al-Antākī. Then, we are interested in observations of comets from the 9th to the end of the 19th century in North Africa and in Islamic Spain (Andalusia), recorded in some Arabic manuscripts on astronomy and history, which have never been the subject of an extensive study. The studied observations are: the two comets X/975 P1 and X/998 D1 reported by an anonymous author of the 15th century, the X/1381 V1 comet reported by Ibn al-Qāḍī (1553-1616), the passage of Halley's comet in 1456 reported by Muḥammad al-Zarkašī (1434-1525), the C/1743 X1 comet observed by ‘Abd al-Razzāq ibn Ḥamadūš (1695-1785), which confirm its fan structure, the two observations of Ibn ‘Alī al-Šrīf al-Šalāṭī of the D/1770 L1, and especially the C/1769 P1 comet. The graphic representation of this latter comet is unprecedented in the Muslim West.

This treatise of medicine by Yühannā ibn Sarābiyūn, written in Syriac in the 8th century, translated into Arabic in the 10th century and then into Latin in the 12th century, is a typical example of the transmission of Hippocratic medicine from the Arabic East to the Latin West in the Middle Ages. However, while the complete Latin translation of Gerard of Cremona has reached us, we have only fragments of the Arabic text, dispersed in five manuscripts preserved in four European libraries.

In the first part we shall try to establish the biographical information about the author and the four translators of his treatise from Syriac to Arabic. In the second part we shall study the Arabic fragments of the Paris manuscript and the two Escorial manuscripts, first by examining their language, and then by comparing them to the Latin translation.

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.

The stages in the development of Averroes' philosophy can be better defined by the revisions Averroes himself made of his works than by the traditional order of his commentaries (short, middle, long); such revisions often take the form of glosses. In his initial stages Averroes' opinions are influenced by the interpretations of Alexander of Aphrodisias and Themistius as well as Avempace. In his final stages, he departs from them and moves closer to Aristotle's original thought. Averroes' reading of the beginning of Physics, Book VIII is an exception: there he agrees with Aristotle in the first stage and moves away from him in the final stage, because he came to believe that Aristotle's purpose in this part of the book was to prove the eternity of heavenly movement. The explanation for the different reading of the introduction to the short commentary can be found in the persecution Averroes and other philosophers suffered in 1197, after which Averroes no longer declared philosophy to be the way to attain human perfection, and he only wanted to illuminate Aristotle's philosophy.

What follows is a detailed study of Averroes's Decisive Treatise based on a new English translation of the text. It seeks to reveal the steps of the exposition, the quality of the reasoning used therein, and the general goal. The study adheres closely to the framework established by Averroes at the outset: namely, that this is an inquiry conducted from the perspective of what is permitted by the divine law of Islam. And it takes seriously the proposition that one can seek for an intelligent and intelligible connection between that law and the results reached through philosophical investigation. Thus, Averroes's ultimate conclusion – that the divine law of Islam and philosophy or wisdom are in basic agreement – is seen to make sense insofar as both seek to provide for the well-being of all members of the community. It makes sense, that is, as an understanding of what governance entails.

This paper deals with a solution to the infamous liar paradox, usually known in the Arabic literature as Maġlaṭat al-ǧaḏr al-aṣamm. The solution is raised by a fifteenth-century Ottoman treatise that is attributed, among others, to Ḫaṭībzāde Muḥyiddīn Efendī. The paper also compares it with the solution by the contemporary Persian philosopher, Ǧalāl al-Dīn al-Dawānī. The short treatise devoted to the paradox is one of the few works by Ottomans on the subject and it comprehensively addresses the paradox in its two forms. An analysis of the solution offered by the treatise to the paradox, the paper aims to bring Ottoman discussions of the liar to the attention of contemporary scholarship and contribute to filling the obvious gap in the literature on the paradox in Islamic thought.

The concept of tawḥīd (unity of God) is a central issue in Kalām theological treatises. The discussion devoted to this concept follows a typical structure, a fact that has been recognized by scholars in the past. Shlomo Pines points to the similarity between the Kalām model of discussion and the structure of John Damascene's (d. 750) De Fide Orthodoxa. Pines suggested that it may indicate the profound impact of Christian theology on Muʿtazilite Kalām. Ulrich Rudolph adds two important pieces of evidence to the discussion: He analyzes Abū Manṣūr al-Māturīdī al-Samarqandī's (d. 944) Kitāb al-Tawḥīd and the Jacobite Moses bar-Kepha's (d. 903) introduction to his Hexaemeron, and argues that the structural and conceptual affinity between them actually indicates an opposite direction of influence than the one suggested by Pines. According to Rudolph, the similarity of the two treatises shows they were written as an imitation of an older Muʿtazilite book, which constituted a prototype for the discussion on the concept of tawḥīd. This paper will challenge Rudolph's thesis in two ways, first by questioning his arguments concerning the sources of the Kitāb al-Tawḥīd, and second by suggesting an alternative assumption, which will strengthen Pines's theory regarding the development of the Kalām model of discussion. Through a comparative structural analysis of the works of Māturīdī and bar-Kepha, together with some fragments of earlier Jewish and Christian commentaries on Genesis, will rise the possibility that this model of discussion existed first in the Christian exegetical treatises assigned to Genesis and had already developed before it appeared in the Kalām works.

One of the most important medieval documents in the history of medicine and scholarship, and of culture in general, is doubtless the bibliographical treatise (“epistle”, Risāla) by Ḥunayn b. Isḥāq (808-873) addressed to his patron and patron of the arts, the gentleman courtier ‘Alī b. Yaḥyā b. al-Munaǧǧim (d. 275 / 888-889), listing the translations of Galen into Syriac and Arabic. Its transmission and publication history, though, is extremely complicated.

In this article, I examine key passages from the Aš῾arite theologian Faḫr al- Dīn al-Rāzī’s (d. 606/1210) final work, Al-Maṭālib al-῾āliya (“ The lofty inquiries ”), in order to theorize Rāzī’s cosmology and angelology. In his attempt to prove the existence of these beings, Rāzī divides reality into material and intelligible realms. Angels, which signify the celestial intellects and spheres, exist as non-space-occupying beings and represent an aspect of the intelligible world. Of these, some are associated with celestial bodies, and others are entirely unassociated with materiality. I then present evidence for the possibility that Rāzī believed that these celestial spiritual beings are pre-eternal with God. These positions indicate a certain degree of conceptual continuity with the falsafa tradition, and reflect al-Ġazālī’s (d. 505/1111) previous integration of the philosophical structure of reality into some of his texts. Additionally, one may look to other philosophical currents that developed in the Islamic world beyond the falāsifa, and connect Rāzī’s cosmology to both the Hermetic tradition and the Epistles of the Iḫwān al-Ṣafā᾿.

This article explores the intimate connection between Avicenna's “flying man” argument and the theory of modes in the school of Abū Hāšim al-Ǧubbā’ī (d. 933). It shows that Avicenna borrows arguments developed originally by Abū Hāšim in order to demonstrate that a definite mode belongs to the living being as a whole (ǧumla). He argues for the incorporeality of soul on the basis of this departure from Aristotelian and Neoplatonic psychology and modal ontology. Here one sees Avicenna's subtle engagement with a thinker to whose writings he reacted critically, yet whom he very likely saw as one of the greatest metaphysicians to write in Arabic.

The first part of this article presents al-Mustamlī al-Buḫārī and his work, a voluminous commentary on al-Kalābāḏī’s compendium of Sufi doctrines, al-Ta‘rruf limaḏhab al-taṣawwuf. Both al-Kalābāḏī and al-Mustamlī had strong tendencies to the discussions of kalām, and of the two al-Mustamlī wrote extensively on theological issues in his commentary, Šarḥ al-Ta‘arruf. In light of the presence of topics of kalām in al-Mustamlī’s book, this article will demonstrate that despite his geographical proximity to Abū Manṣūr al-Māturīdī’s theological school, al-Mustamlī was probably a follower of Abū l-Ḥasan al-Aš‘arī. The second part of the article concerns al-Mustamlī’s discussion of the nature of spirit (rūḥ). It will be argued that in dealing with the nature of the spirit, al-Mustamlī goes beyond the physicalist anthropology of the kalām and presents an argument for the existence of the spirit that has some affinities with Avicenna's proof of the existence of human rational soul, as it appears in the context of his famous thought experiment, the “flying man”. In both parts, the main claim of this article is that al-Mustamlī’s book is a valuable source for understanding the intellectual history of Transoxiana, and the intricate interactions of different disciplines, kalām, falsafa, taṣawwuf with each other.

The “lost” Yaḥyā ibn ʿAdī treatises recently discovered in the Tehran codex Marwī 19 include a record of a philosophical debate instigated by the Ḥamdānid prince Sayf-al-Dawla. More precisely, Marwī 19 contains Yaḥyā’s adjudication of a dispute between an unnamed Opponent and Yaḥyā’s younger relative Ibrāhīm ibn ʿAdī (who also served as al-Fārābī’s assistant), along with Ibrāhīm's response to Yaḥyā’s adjudication, and Yaḥyā’s final word. At issue was a problem of Aristotelian exegesis: should “body” be understood as falling under the category of substance or under the category of quantity? The unnamed Opponent argues that body is a species of substance; Ibrāhīm argues that technically speaking, body is a species of quantity, and hence an accident; and Yaḥyā judges that body is a species of substance, though for very different reasons than the Opponent gives. For the first time, the Arabic text of this exchange is edited and translated into English. Also provided is an Introduction that sets the debate in historical context, and discusses in particular the possible influence of John Philoponus. The debate is interesting and important not only because of the philosophical ramifications of the issues under discussion, but because it constitutes evidence of dialectical practice among Arabic-speaking philosophers from the middle of the 10th century.

Le fr. 2 de Boéthos de Sidon est transmis par deux commentateurs alexandrins des Catégories d'Aristote. En voici le texte grec:

[2a] Ioannes Philoponus, In Aristotelis Categorias commentarium, 5.15-20

Τρίτον ἦν ἐφεξῆς κεφάλαιον τὸ πόθεν δεῖ ἄρχεσθαι τῶν Ἀριστοτελι-[16]κῶν συγγραμμάτων. Βόηθος μὲν οὖν φησιν ὁ Σιδώνιος δεῖν ἀπὸ τῆς [17] φυσικῆς ἄρχεσθαι πραγματείας ἅτε ἡμῖν συνηθεστέρας καὶ γνωρίμου, δεῖν [18] δὲ ἀεὶ ἀπὸ τῶν σαφεστέρων ἄρχεσθαι καὶ γνωρίμων. ὁ δὲ τούτου δι-[19]δάσκαλος Ἀνδρόνικος ὁ Ῥόδιος ἀκριβέστερον ἐξετάζων ἔλεγε χρῆναι πρό-[20]τερον ἀπὸ τῆς λογικῆς ἄρχεσθαι, ἥτις περὶ τὴν ἀπόδειξιν καταγίνεται.

In this paper, I propose to expose the logical structure al-Bāqillānī's argument for the existence of God and argue that it presents a distinctive type of argument that cannot be classified under the classical types of ontological, cosmological, and design arguments. The peculiarity of al-Bāqillānī's argument is related to the concept of God it presupposes. Developing Herbert Davidson's insights regarding this argument and criticizing Majid Fakhry's interpretation of it, I aim to clarify this concept of God by the concept of agency. In a nutshell, I argue that al-Bāqillānī presents a distinctive type of argument for the existence of God, which I propose calling the “cosmological argument from agency.” I consider it cosmological because it is an inference from the universe to the existence of God. Nonetheless, it is different from the classical versions of the cosmological argument for that the concept of agency and the idea of a personal deity play a central role in this argument.

In an article published in Arabic Sciences and Philosophy 22 (2012), pp. 217–87, by Gad Freudenthal and Mauro Zonta, “Avicenna among Medieval Jews: the reception of Avicenna's philosophical, scientific and medical writings in Jewish cultures, East and West,” the authors promise to present “a preliminary but comprehensive picture of Avicenna's reception by medieval Jewish cultures.” As such, it seemed to offer the “comprehensive study” referred to as a desideratum by Zonta at the conclusion of his groundbreaking and very important survey, “Avicenna in medieval Jewish philosophy” (2002). Zonta explained that such a future “comprehensive study of the many and different interpretations given to his doctrines by Jewish thinkers would allow us to evaluate the real role played by [Avicenna] in medieval thought.” Surprisingly, the recent article adds little that is new to the previous studies of Zonta and others on the subject, and omits useful information found in them. The main point of the present notes is to try to correct several oversimplifications, questionable assumptions, and misleading statements in the article under consideration. Its purpose is to help readers of the article to attain a fuller and more accurate – although certainly not comprehensive – picture of the reception of Avicenna among medieval Jews.

Les correspondances littérales relevées dans I.R.M. et F.D.G. conduisent naturellement à se demander si elles sont le signe d'une parenté entre ces deux textes et, si c'est le cas, à s'interroger sur le degré d'originalité de la doctrine rhétorique du premier de ces traités.

The aim of this article is to present a medieval Arabic report regarding six animals from the Gulf of Aden, to provide a zoological identification of five of the animals in question, which may be identified, and to comment on the biological data provided by the report in the light of both contemporary and modern zoological knowledge and, thus, to evaluate the scientific standard of the report.

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.