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.

The famous philosopher and scientist Abū ʿAlī b. Sīnā (d. 428/1037) had an exceptional command of all the subjects on which he wrote. He is especially known for his many writings in logic, philosophy, and medicine. His influence was such that even in Europe, his works on physics, metaphysics and medicine in particular, were widely studied until the beginning of modern times. A keen mind, he had a full understanding of the inner structure of the Islamo-Hellenistic tradition that he perpetuated and in places helped to develop and reshape. This is not only borne out by his many writings, but in some instances also by his explicit accounts of the sciences and their divisions. This article contains an edition of one such account, of which only two copies have been identified so far. It will be argued (against Biesterfeldt) that the text in question is likely to have been written in Bukhārā when Avicenna was still in his early twenties. Moreover, it will be shown that it could very well be that the text was actually copied from his famous Al-ḥāṣil wal-maḥṣūl (Harvest reapings), a philosophical encyclopaedia in twenty volumes long since lost. The absence of algebra and a philosophical rather than a religious foundation of the sciences finally, are important clues to Avicenna's perspective on the rational sciences early in his career.

A key work for the study of pre-modern Platonism, Galen's (d. ca. 217 CE) “Synopsis of Plato's Timaeus” (Com. Tim.) is served solely by an “imperfect” 1951 edition that presents for the first time the surviving Arabic text and translates it into Latin. The editors of the “Plato Arabus” series of the Corpus Platonicum, to which the edition belongs, blamed its flaws on the untimely death of Paul Kraus (1904-1944), who prepared the edition with another Jewish refugee Richard Walzer (1900-1975) around WWII. My analysis of archival sources will demonstrate that the labor on the volume was disproportionately Kraus’, whom Walzer and the Corpus Platonicum editor Raymond Klibansky (1905-2005) marginalized from the project in their attempts to secure employment in British academia as displaced Jews. I will also consider how Walzer and Klibansky re-envisioned Kraus’ plans for a Semitic corpus of Platonism to a narrower “Plato Arabus” that would align with a study of Latin Platonism (“Plato Latinus”) in which they presumed their British patrons would be more interested.

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.

The Arabic text of Boethus fr. 44 Rashed has, pace Rashed (p. 266), a parallel in a Greek scholium to Galen's De elementis ex Hippocratis sententia. The scholium occurs in the sets of scholia to De elem. in Paris BNF suppl. gr. 634 (= Π; saec. xii) and in El Escorial Φ.II.15 (= Σ; saec. xiii). The former set was edited by G. Helmreich in Handschriftliche Studien zu Galen, vol. I. The relevant passage occurs in Π fol. 21 r ult. – v 3 (= schol. 34 p. 12 Helmr.) and in Σ fol. 136 r 7-11. The polysyllogism ascribed to Boethus reads: τὸ ὅμοιον ὑπὸ τοῦ ὁμοίου γινώσκεται. ἡ αἴσθησις τὰ στοιχεῖα γινώσκει. ἡ αἴσθησις ἄρα ὁμοία τοῖς στοιχείοις … ἡ αἴσθησις ὁμοία τοῖς στοιχείοις. τὸ ὅμοιον ἐκ τοῦ ὁμοίου [γινώσκεται]. ἡ αἴσθησις ἄρα ἐκ τῶν στοιχείων [γινώσκεται].

That Ibn Sīnā’s “Canon of medicine” figures among the major classics of the history of medicine is doubted by no serious historian of medicine, eastern or western, Islamic or non-Islamic alike. It is therefore all the more surprising that so far no serious critical edition of this text was available. Certainly, a first, very timid step toward a really critical edition (published during the years 1982-1996) was made at the Institute of the History of Medicine and Medical Research (New Delhi), under the direction of Hakeem Abdul Hameed (1908-1999). It compared the four existing editions: Rome 1593; Būlāq (Cairo) 1877; Tehran (lithograph) 1878; and Lucknow 1905. In addition it used (a photocopy of) an ancient manuscript of Aya Sophia, dated 618, i. e. MS Aya Sophia 3686. With this new edition a further important step toward a full critical edition is made. Even if it is obvious that it does not yet present a “critical edition” in the full sense of the word, it has important merits.