RésuméLa théorie avicenienne du mouvement des orbes célestes représente un aspect important de sa cosmologie qui n'a cependant pas encore été l'objet d'une étude approfondie. Cet article compte combler ce manque en fournissant une analyse des différents principes à l'origine du mouvement céleste, ainsi qu'une réflexion sur le rôle des disciplines astronomique, physique, et métaphysique dans les explications que fournit Ibn Sīnā à ce sujet. L'accent est mis sur le rapport des intelligences aux orbes et sur la problématique du passage (...) de l'intellectif au physique, un moment charnière dans la cinématique avicenienne. En outre, l'étude remet en question l'adhésion d'Ibn Sīnā à la théorie farabienne des dix intelligences et entreprend une reconstitution de son modèle cosmologique. (shrink)

This dissertation offers a new and comprehensive analysis of Abū Naṣr al-Fārābī's cosmology by focusing on various important issues that have been largely neglected by the modern scholarship. It provides an examination of the physical, metaphysical, and astronomical aspects of al-Fārābī's cosmology by adopting a multidisciplinary approach that takes into account the history of philosophy and the history of astronomy. Accordingly, my dissertation explores how al-Fārābī attempted to reconcile features of Ptolemaic astronomy with Aristotelian and Neoplatonic theories, an endeavor which (...) resulted in the formulation of innovative cosmological ideas. Chapters I and II provide background information on al-Fārābī's activity as a commentator and his relation to the Greek commentatorial tradition and assess the relevant primary sources. In addition, they examine al-Fārābī's approach to cosmology and his scientific method in terms of both the Ptolemaic astronomical tradition and the Aristotelian corpus. Chapter III addresses problems related to the structure of al-Fārābī's cosmology, especially the origin of his ennadic cosmological model and his spherology. Particular attention is devoted to the question of how Aristotle's unmoved movers and Ptolemy's astronomical theories are reconciled. Chapters IV, V, and VI analyze the place of celestial matter, intellect, and motion respectively in al-Fārābī's cosmology and attempt to redefine the second teacher's relation to the various trends of Greek philosophy. The study stresses al-Fārābī's connection with the Neoplatonic and Peripatetic currents, particularly with thinkers such as Alexander of Aphrod. (shrink)