This category is dedicated to Aristotle (382-322BC), the Greek philosopher born in Stagyra, Macedonia. A student of Plato's Academy, he left when a rival was named head and became tutor to Alexander the Great. He later founded his own Athenian school, the Lyceum, but ended his life in exile in the wake of Alexander's death and resurgent anti-Macedonian feeling.

Aristotle was a materialist, standing in contrast to his mentor Plato, an idealist; that is, he theorized that substance is the nexus of both form and matter. He was the first philosopher to observe the use of definition, induction, and deduction in the formation of knowledge, and to attempt to correlate all human knowledge into a comprehensive system of ideas. The invention of the syllogism is attributed to him.

His contributions to philosophy are too numerous and far-reaching to adequately outline in this space; he impacted the academic study of logic, politics, rhetoric, linguistics, and literature, among other fields. The rediscovery of Aristotle's works in large measure propelled the Italian Renaissance, but also served to undermine the advance of modern science.