Socrates

Socrates wrote nothing, and yet Western philosophy begins with him. An Athenian stonemason's son who served as a hoplite in the Peloponnesian War, he spent his life in the agora practicing what he called elenchus — cross-examination. He would ask a general to define courage, a priest to define piety, an orator to define justice, and then show, question by question, that the confident answer collapsed under its own weight. What survives of him comes through his students, above all Plato, whose early dialogues — the Euthyphro, Apology, and Crito — are our closest witnesses.

Two convictions organize everything he did. First, that the unexamined life is not worth living for a human being: a claim he made at his own trial, as Plato records in the Apology. Second, that no one does wrong willingly — vice, for Socrates, is a form of ignorance, and virtue a form of knowledge. If a person truly knew what was good, they would do it; wrongdoing is always a miscalculation about what benefits the soul.

His method mattered as much as his doctrine. The Euthyphro poses a question that still shadows every theology: is the pious loved by the gods because it is pious, or pious because they love it? The dilemma — whether morality is independent of divine will or arbitrary — remains a live argument in philosophy of religion twenty-four centuries later.

In 399 BC, an Athenian jury convicted him of impiety and corrupting the young. Offered escape by his friends, he refused, arguing in the Crito that he owed the laws of Athens his obedience even when they erred against him. He drank the hemlock among his students. His death did what his life had begun: it made philosophy a calling for which a person might die, and every school that followed — Platonist, Cynic, Stoic, Skeptic — claimed him as its founder.