This cosmological study presents a universe composed of concentric spheres, with the earth fixed at the center and the heavens moving in eternal circles. Aristotle differentiates the corruptible matter of the earth from the incorruptible “aether” of the stars, establishing a dual physics for the cosmos. The text argues for the finiteness of the universe and explores the properties of heavy and light bodies. It is a grand attempt to systematize the physical structure of the entire universe based on observation and logical deduction.
