Part 2 of the Natural Philosophy Section of the Shifāʾ

In the introduction to ʿIllat qiyām al-arḍ, Ibn Sīnā tells us that he has written a work entitled al-Samāʾ wa-al-ʿālam. (Pace Sezgin and Mahdavi, this is not called a “tafsīr,” at least not in the printed version; nor is there any indication that it was a commentary on Aristotle’s De caelo.) He wrote this for Abū al-Ḥusayn Aḥmad al-Sahlī [Suhaylī?], to whom the ʿIllat was also dedicated. Thus this would have been composed long before the Shifāʾ was completed. Was this then a completely different work from what we have in the Shifāʾ? As we might expect, the extant al-Samāʾ wa-al-ʿālam does not contain a dedication to al-Sahlī, so at least some modification has taken place. On the other hand, it would seem unlikely that Ibn Sīnā, given his busy schedule and hectic life, would have written a completely new De caelo for the Shifāʾ.

One should note, however, that there is a different work in Latin translation that goes under the title of Avicenna’s De celo et mundo, which was printed in Venice with several of his other works in 1508 (I, ff. 37-42). This work has sixteen chapters whereas the De caelo of the Arabic Shifāʾ has ten. Could this be the earlier version mentioned in the ʿIllat? Probably not; cf. Janssens, who refers to it as pseudo-Avicenna ([1991], p. 275).
The medieval Latin translation of the extant Arabic work has been edited by Renaud [1973] based upon a single Vatican manuscript (Vat. Lat. 186, ff. 83r-102v); the translation is reasonably close to the Arabic original.