Deux opuscules nous sont parvenus de Thābit ibn Qurra sur la théorie des parallèles. Ces deux traités sont bien connus et ont fait déjà l'objet de plusieurs commentaires et traductions. Nous pensons reprendre ici aussi bien l'édition que la traduction et le commentaire pour mieux situer la contribution de Thābit ibn Qurra après la publication récente de ses œuvres en astronomie et en mathématiques.

In an influential article, A. I. Sabra identified an intellectual trend from twelfth and thirteenth-century Andalusia which he described as the ‘‘Andalusian revolt against Ptolemaic astronomy.” Philosophers such as Ibn Rushd (d. 1198 C. E.), Ibn Tufayl (d. 1185), and Maimonides (d. 1204) objected to Ptolemy’s (fl. 125–50) theories on philosophic grounds, not because of shortcomings in the theories' predictive accuracy. Sabra showed how al-Bitrūjī's (fl. 1200) Kitāb al-Hay'a (The Book of Astronomy) attempted to account for observed planetary motions in a way that met the philosophic standards of those philosophers and others. In Nūr al-‘ālam (Light of the World), the subject of this article, Joseph ibn Joseph ibn Nahmias (fl. ca. 1400) endeavoured to improve upon al-Bitrūjī’s models. Levi Ben Gerson's (1288–1344) Hebrew writings on astronomy criticized al-Bitrūjī, but Ibn Nahmias did not mention them. Nūr al-‘ālam deserves attention, too, because it is the first Arabic text on theoretical astronomy by a Jewish author to come to light. In the body of this article, I will describe and analyze Ibn Nahmias’ theory, from Nūr al-‘ālam, for the motion of the sun.

Dans ses traités consacrés à l'âme, Ibn Sīnā élabore une doctrine complexe de la perception dont l'analyse permet de dégager deux conceptions distinctes de l'image. L'une détermine l'image comme une doublure du réel, qui re-présente quelque chose, et tient lieu d'une chose absente. Cette caractérisation de l'image comme un double et une entité matérielle qui se forme dans les puissances-organes comme par réification s'inscrit dans la conception antique et médiévale de l'image. L'image, dans l'horizon épistémique de l'Antiquité et du Moyen Âge, n'est jamais conçue, en effet, que dans sa relation à ce qu'elle représente. Le statut ontologique de cette image-reflet est celui d'un double: c'est un reflet que sa matérialité rend manifeste.

According to Tāj al-Dīn al-Subkī (d. 771 / 1370), al-Ghazālī (d. 505 / 1111) was the renewer (mujaddid) of the Muslim faith at the end of the 5th / 11th century, whereas al-Rāzī (d. 606 /1210) was the renewer of faith at the end of the 6th / 12th century. That al-Ghazālī deserves such an honour can hardly be disputed, and his importance in the history of Islamic thought is generally recognised. However, the same cannot, as easily, be said of al-Rāzī, whose historical significance is far from being truly appreciated, and some of the most important books of whom still await publication. Much is known about his views on particular philosophical and theological problems, and about the historical backgrounds to, and the relations amongst, some of these views. Some rather general observations on his thought are also common; for instance, that he is a heavily philosophising Ash‘arī mutakallim, a master dialectician, and an influential critic of Ibn Sīnā.