"Aristotle believed that the outermost stars are carried around the earth on a transparent sphere, that there are directions in the universe and a preferred direction of rotation. The sun, moon, and planets are carried on different revolving spheres. The spheres and celestial bodies are composed of an everlasting fifth element, which has none of the ordinary contrary properties like heat and cold, which could destroy it, but only the facility for uniform rotation. But this belief raises the question of how the heavenly bodies create light and, in the case of the sun, heat." "The topics covered in this part of Simplicius' commentary on On the Heavens are the speeds and distances of the stars; that the stars are spherical; why the sun and moon have fewer motions that the other five planets; why the sphere of the fixed stars contains so many stars whereas the other heavenly spheres contain no more than one (Simplicius has a long excursus on planetary theory in his commentary on this chapter); discussion of people's views on the position, motion or rest, shape, and size of the earth; and that the earth is a relatively small sphere at rest in the center of the cosmos."--BOOK JACKET.

"Aristotle believed that the outermost stars are carried round us on a transparent sphere. There are directions in the universe and a preferred direction of rotation. The sun moon and planets are carried on different revolving spheres. The spheres and celestial bodies are composed of an everlasting fifth element, which has none of the ordinary contrary properties like heat and cold which could destroy it, but only the facility for uniform rotation. But this creates problems as to how the heavenly bodies create light, and, in the case of the sun, heat. The topics covered in this part of Simplicius' commentary are the speeds and distances of the stars; that the stars are spherical; why the sun and moon have fewer motions than the other five planets; why the sphere of the fixed stars contains so many stars whereas the other heavenly spheres contain no more than one (Simplicius has a long excursus on planetary theory in his commentary on this chapter); discussion of people's views on the position, motion or rest, shape, and size of the earth; that the earth is a relatively small sphere at rest in the centre of the cosmos."--Bloomsbury Publishing.

Aristotle argues in On the Heavens 1.5-7 that there can be no infinitely large body, and in 1.8-9 that there cannot be more than one physical world. As a corollary in 1.9, he infers that there is no place, vacuum or time beyond the outermost stars. As one argument in favour of a single world, he argues that his four elements: earth, air, fire and water, have only one natural destination apiece. Moreover they accelerate as they approach it and acceleration cannot be unlimited. However, the Neoplatonist Simplicius, who wrote the commentary in the sixth century AD (here translated into English), tells us that this whole world view was to be rejected by Strato, the third head of Aristotle's school. At the same time, he tells us the different theories of acceleration in Greek philosophy.

Aristotle believed that the outermost stars are carried round us on a transparent sphere. There are directions in the universe and a preferred direction of rotation. The sun, moon and planets are carried on different revolving spheres. The spheres and celestial bodies are composed of an everlasting fifth element, which has none of the ordinary contrary properties like heat and cold which could destroy it, but only the facility for uniform rotation. But this creates problems as to how the heavenly bodies create light, and, in the case of the sun, heat. The topics covered in this part of Simplicius' commentary are: the speeds and distances of the stars; that the stars are spherical; why the sun and moon have fewer motions than the other five planets; why the sphere of the fixed stars contains so many stars whereas the other heavenly spheres contain no more than one (Simplicius has a long excursus on planetary theory in his commentary on this chapter); discussion of people's views on the position, motion or rest, shape, and size of the earth; that the earth is a relatively small sphere at rest in the centre of the cosmos.

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 companion to J. O. Urmson's translation in the same series of Simplicius' Corollaries on Place and Time contains Simplicius' commentary on the chapters on place and time in Aristotle's Physics book 4. It is a rich source for the preceding 800 years' discussion of Aristotle's views. Simplicius records attacks on Aristotle's claim that time requires change, or consciousness. He reports a rebuttal of the Pythagorean theory that history will repeat itself exactly. He evaluates Aristotle's treatment of Zeno's paradox concerning place. Throughout he elucidates the structure and meaning of Aristotle's argument, and all the more clearly for having separated off his own views into the Corollaries.