The existence of common points between Alexander of Aphrodise and Bardaisan the Syrian has been pointed out on various occasions. However, this question has not been explored in depth. The article proposes to analyse the cosmological ideas of Alexander and Bardaisan. Because both authors are known for their anti-determinist and anti-astrological polemics, it is preferable to place this comparison in the context of the astrological interpretation of Aristotle’s natural philosophy. The article discusses the Aristotelianism of Bardaisan, who may be the (...) first representative of the reception of this doctrine in Syriac. (shrink)