Aristotle

Key ideas

Aristotle's ethics asks what the good life is, and answers with eudaimonia: flourishing, the full exercise of the capacities that make us human, above all reason. Virtues are stable traits of character, each a mean between two extremes, as courage lies between cowardice and recklessness. They are acquired through practice, the way one becomes a builder by building. This is the root of modern virtue ethics.

In logic he developed the syllogism, the first formal system of valid inference, which dominated the subject for two thousand years. In metaphysics he analysed change through matter and form and through potentiality and actuality, and distinguished four kinds of cause, including the final cause, the purpose a thing serves.

He also answered Zeno of Elea by distinguishing potential from actual infinity, wrote on the soul as the form of a living body, and asked whether statements about tomorrow's sea battle are already true, a puzzle that still feeds debates about fatalism.

“All men by nature desire to know.”

Aristotle, Metaphysics I.1, trans. W. D. Ross (1908)

Life, briefly

Aristotle was born in Stagira in northern Greece, the son of a court physician to the king of Macedon. At seventeen he joined Plato's Academy and stayed for about twenty years. Later he tutored the young Alexander the Great.

In 335 BCE he founded his own school in Athens, the Lyceum, and did much of his research in biology there. After Alexander's death, anti-Macedonian feeling led him to leave Athens; he died the following year. What survives is mostly lecture notes, which is one reason his prose is so dense.

Major works

• Nicomachean Ethics
• Politics
• Metaphysics
• Physics
• On the Soul
• Prior Analytics
• Poetics

Schools of thought

Virtue ethics

Further reading

• EncyclopediaStanford Encyclopedia of Philosophy: Aristotle
• WikipediaAristotle