Book 2 of the Physics is arguably the best introduction to Aristotle's work, both because it explains some of his central concepts, such as nature and the four causes, and because it asks some gripping questions that are still debated today: Is chance something real? If so, what? Can nature be explained by chance, necessity and natural selection, or is it purposive? Philoponus' commentary is not only a valuable guide, but also a work of Neoplatonism with its own views on causation, the Providence of Nature, the problem of evil and the immortality of the soul.

This book considers the concepts that lay at the heart of natural philosophy and physics from the time of Aristotle until the fourteenth century. The first part presents Aristotelian ideas and the second part presents the interpretation of these ideas by Philoponus, Albertus Magnus, Thomas Aquinas, John Buridan, and Duns Scotus. Across the eight chapters, the problems and texts from Aristotle that set the stage for European natural philosophy as it was practiced from the thirteenth to the seventeenth centuries are considered first as they appear in Aristotle and then as they are reconsidered in the context of later interests. The study concludes with an anticipation of Newton and the sense in which Aristotle's physics had been transformed.

Book 2 of the Physics is arguably the best introduction to Aristotle's ideas, as well as being the most interesting and representative book in the whole of his corpus. It defines nature and distinguishes natural science from mathematics. It introduces the seminal idea of four causes, or four modes of explanation. It defines chance, but rejects a theory of chance and natural selection in favour of purpose in nature. Simplicius, writing in the sixth century AD, adds his own considerable contribution to this work. Seeing Aristotle's God as a Creator, he discusses how nature relates to soul, adds Stoic and Neoplatonist causes to Aristotle's list of four, and questions the likeness of cause to effect. He discusses missing a great evil or a great good by a hairsbreadth and considers whether animals act from reason or natural instinct. He also preserves a Posidonian discussion of mathematical astronomy.

This is the first translation into English of the sixth-century philosopher Philoponus' commentary on Aristotle Physics, book four, chapters one to five.

Originally published in 1991. Philoponus’ long commentary on Aristotle’s definition of light sets up the major concerns, both in optics and theory of light, that are discussed here. Light was of special interest in Neoplatonism because of its being something incorporeal in the world of natural bodies. Light therefore had a special role in the philosophical analysis of the interpenetration of bodies and was also a paradigm for the soul-body problem. The book contains much about the physiology of vision as well as the propagation of light. Several chapters investigate the philosophical theory behind what came to be known as ‘multiplication of species’ in medieval light theory. These issues in the history of science are placed within an analysis of Neoplatonic development of the distinction between Aristotle’s kinesis and energeia. The book treats Philoponus’ philosophy of mathematical science from the point of view of matter, quantity, and three-dimensionality.

Book 3 of Aristotle's Physics primarily concerns two important concepts for his theory of nature: change and infinity. Change is important because, in Book 2, he has defined nature - the subject-matter of the Physics - as an internal source of change. Much of his discussion is dedicated to showing that the change occurs in the patient which undergoes it, not in the agent which causes it. Thus Book 3 is an important step in clearing the way for Book 8's claims for a divine mover who causes change but in whom no change occurs. The second half of Book 3 introduces Aristotle's doctrine of infinity as something which is always potential, never actual, never traversed and never multiplied. Here, as elsewhere, Philoponus the Christian turns Aristotle's own infinity arguments against the pagan Neoplatonist belief in a beginningless universe. Such a universe, Philoponus replies, would involve actual infinity of past years already traversed, and a multiple number of past days. The commentary also contains intimations of the doctrine of impetus - which has been regarded, in its medieval context, as a scientific revolution - as well as striking examples of Philoponus' use of thought experiments to establish philosophical and broadly scientific conclusions.

Presents a survey of what Arabic philosophers, as commentators of Aristotle's Physics, have contributed to philosophy and science in the Middle Ages. Their influences on each other and the extent of the influences of previous Greek commentators on them, are also examined.