On the Heavens

Methodology and Conclusions

In «On the Heavens», Aristotle employs a deductive method of investigation based on observations and logical reasoning. He seeks to explain the nature of celestial bodies and their movements, relying on philosophical and physical principles. Aristotle considers celestial bodies to be perfect and unchanging, asserting that they consist of a special fifth element — aether, distinct from the four earthly elements (earth, water, air, and fire). He concludes that celestial bodies move in circular orbits because circular motion is the most perfect and constant. Aristotle also discusses the structure of the universe, asserting that Earth is at the center, with all celestial bodies revolving around it. His conclusions are based on observations of the movement of stars and planets, as well as philosophical reflections on the nature of motion and matter.