The subject of Aristotle's On the Heavens, Books 3-4, is the four elements of earth, air, fire and water, which exist below the heavens. Book 3, in chapters 1 to 7, frequently criticizes the Presocratic philosophers. Because of this, Simplicius' commentary is one of our main sources of quotations of the Presocratics. Ian Mueller's translation of this commentary gains added importance by enabling us to see the context which guided Simplicius' selection of Presocratic texts to quote. Simplicius also criticizes the lost commentary of the leading Aristotelian commentator, Alexander, and thereby gives us important information about that work. The English translation in this volume is accompanied by a detailed introduction, extensive commentary notes and a bibliography.

Supporting the twelve volumes of translation of Simplicius' great commentary on Aristotle's Physics, all published by Bloomsbury in the Ancient Commentators on Aristotle series, between 1992 and 2021, this volume presents a general introduction to the commentary. It covers the philosophical aims of Simplicius' commentaries on the Physics and the related text On the Heaven; Simplicius' methods and his use of earlier sources; and key themes and comparison with Philoponus' commentary on the same text. Simplicius treats the Physics as a universal study of the principles of all natural things underlying the account of the cosmos in On the Heaven. In both treatises, he responds at every stage to the now lost Peripatetic commentaries of Alexander of Aphrodisias, which set Aristotle in opposition to Plato and to earlier thinkers such as Parmenides, Empedocles and Anaxagoras. On each passage, Simplicius after going through Alexander's commentary raises difficulties for the text of Aristotle as interpreted by Alexander. Then, after making observations about details of the text, and often going back to a direct reading of the older philosophers (for whom he is now often our main source, as he is for Alexander's commentary), he proposes his own solution to the difficulties, introduced with a modest 'perhaps', which reads Aristotle as in harmony with Plato and earlier thinkers.

Commenting on the end of Aristotle's On the Heavens Book 3, Simplicius examines Aristotle's criticisms of Plato's theory of elemental chemistry in the Timaeus. Plato makes the characteristics of the four elements depend on the shapes of component corpuscles and ultimately on the arrangement of the triangles which compose them. Simplicius preserves and criticizes the contributions made to the debate in lost works by two other major commentators, Alexander the Aristotelian, and Proclus the Platonist. In Book 4, Simplicius identifies fifteen objections by Aristotle to Plato's views on weight in the four elements. He finishes Book 4 by elaborating Aristotle's criticisms of Democritus' theory of weight in the atoms, including Democritus' suggestions about the influence of atomic shape on certain atomic motions. This volume includes an English translation of Simplicius' commentary, a detailed introduction, extensive commentary notes and a bibliography.

This is the first English translation of Simplicius' responses to Philoponus' Against Aristotle on the Eternity of the World. The commentary is published in two volumes: Ian Mueller's previous book in the series, Simplicius: On Aristotle On the Heavens 1.2-3, and this book on 1.3-4. Philoponus, the Christian, had argued that Aristotle's arguments do not succeed. For all they show to the contrary, Christianity may be right that the heavens were brought into existence by the only divine being and one moment in time, and will cease to exist at some future moment. Simplicius upholds the pagan view that the heavens are eternal and divine, and argues that their eternity is shown by their astronomical movements coupled with certain principles of Aristotle. The English translation in this volume is accompanied by a detailed introduction, extensive commentary notes and a bibliography.

One of the arguments in Aristotle's On the Heavens propounds that the world neither came to be nor will perish. This volume contains the pagan Neoplatonist Simplicius of Cilicia's commentary on the first part of this this important work. The commentary is notable and unusual because Simplicius includes in his discussion lengthy representations of the Christian John Philoponus' criticisms of Aristotle along with his own, frequently sarcastic, responses. This is the first complete translation into a modern language of Simplicius' commentary, and is accompanied by a detailed introduction, extensive explanatory notes and a bibliography.

Simplicius' greatest contribution in his commentary on Aristotle on Physics 1.5-9 lies in his treatment of matter. The sixth-century philosopher starts with a valuable elucidation of what Aristotle means by 'principle' and 'element' in Physics. Simplicius' own conception of matter is of a quantity that is utterly diffuse because of its extreme distance from its source, the Neoplatonic One, and he tries to find this conception both in Plato's account of space and in a stray remark of Aristotle's. Finally, Simplicius rejects the Manichaean view that matter is evil and answers a Christian objection that to make matter imperishable is to put it on a level with God. This is the first translation of Simplicius' important work into English.

There has recently been considerable renewed interest in Book 7 of the Physics of Aristotle, once regarded as merely an undeveloped forerunner to Book 8. The debate surrounding the importance of the text is not new to modern scholarship: for example, in the fourth century BC Eudemus, the Peripatetic philosopher associate of Aristotle, left it out of his treatment of the Physics. Now, for the first time, Charles Hagen's lucid translation gives the English reader access to Simplicius' commentary on Book 7, an indispensable tool for the understanding of the text. Its particular interest lies in its explanation of how the chapters of Book 7 fit together and its reference to a more extensive second version of Aristotle's text than the one which survives today.