This is the first translation into English of the commentary of the sixth-century philosopher Philoponus on Aristotle's Physics Book 4, chapters 6-9. In this section of his commentary, Philoponus attacks Aristotle's views on void (or vacuum) and motion.

The Ancient Commentators on Aristotle series is a prestigious scholarly project, which translates into English the principal works of the Neoplatonist commentators on Aristotle. The translation in each volume is accompanied by an introduction, comprehensive commentary notes, bibliography, glossary of translated terms and a subject index. Praise for the series: "A truly breathtaking achievement, with few parallels in the history of scholarly endeavour" Times Literary Supplement "Well-known and renowned" Bryn Mawr Classical Review "One of the great scholarly achievements of our time" British Journal for the History of Philosophy "Without any doubt, it is this enterprise of R. Sorabji which has had the greatest impact among historians of ancient philosophy." Ilsetraut Hadot in Le Néoplatonicien Simplicius à la lumière des recherches contemporaines