Plato

Plato (c. 428–348 BC) was born into one of the leading families of Athens. As a young man he became a follower of Socrates, and the trial and execution of his teacher in 399 BC turned him from a political career to philosophy. After travels in Italy and Sicily he founded the Academy in Athens, the first school of its kind, where he taught for some forty years; Aristotle was among his students.

Plato wrote almost all his works as dialogues — conversations in which Socrates is usually the leading speaker. Some thirty-five dialogues and a collection of letters have come down under his name, the first complete body of work by a Greek philosopher to survive. They range from the early Socratic dialogues on courage, piety and virtue, through the great works of his maturity, the Phaedo, the Symposium and the Republic, to the late Timaeus and Laws.

Plato's questions — what justice is, what we can know, what the soul is, how a good city should be ordered — set the course of Western philosophy. The philosopher Alfred North Whitehead could say that the European philosophical tradition consists of a series of footnotes to Plato.