On the Heavens

Aristotle (384 BC – 322 BC) was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings were the first to create a comprehensive system of Western philosophy, encompassing morality, aesthetics, logic, science, politics, and metaphysics. On the Heavens is his chief cosmological treatise. It contains astronomical theory and ideas on the concrete workings of the terrestrial world. He devotes most of his attention to developing his elaborate cosmological theory on how the matter of the universe is shaped, how it occupies space and time. He also provides a detailed explanation of his theory of gravity arguing that things which contain earth fall towards the centre of the universe because earth is naturally attracted to the centre of the universe. He also offers a treatment of the elements—water, air, earth, and fire—and proposes an explanation regarding how each of these is comprised and what types of effects one exerts over the other.