Plato

Plato was a Greek philosopher, a student of Socrates and the teacher of Aristotle, and the founder of the Academy in Athens. His dialogues are among the foundational works of Western philosophy, and his theory of forms shaped metaphysics and epistemology for centuries.

Life

Plato was born in Athens around 428 BC into an aristocratic family. He was a follower of Socrates, whose trial and execution profoundly affected him and who appears as the central figure in most of his dialogues.

After the death of Socrates, Plato travelled in Greece, Egypt, and Italy, where he encountered Pythagorean thought. He founded the Academy in Athens around 387 BC, an institution that lasted for centuries and is often described as the first university.

He died in Athens around 348 BC. His dialogues, written over several decades, survive largely intact and are the main source for his philosophy.

The Dialogues

The dialogues are divided into early, middle, and late periods. The early dialogues, including the Apology and the Euthyphro, examine the definitions of virtues and portray Socrates as a questioner who refutes the pretensions of his interlocutors.

The middle dialogues, including the Phaedo, the Symposium, and the Republic, develop Plato's own doctrines, including the theory of forms and the immortality of the soul. The late dialogues, including the Sophist and the Laws, examine logic, language, and political theory.

The Theory of Forms

The theory of forms holds that the objects of the sensible world are imperfect copies of eternal and unchanging forms. The forms are the true objects of knowledge, while the objects of sense are the objects of opinion.

The theory provides the basis for Plato's epistemology, in which knowledge is of the forms and is attained by reason rather than by the senses. It also provides the basis for his ethics, in which the good is the highest form.

The Republic

The Republic examines the nature of justice and of the ideal state. It presents the analogy between the soul and the state, and it argues that the just state is one in which each part performs its proper function.

The dialogue includes the allegory of the cave, in which the philosopher is compared to a prisoner who escapes from a cave and sees the light of the sun. It also presents the theory of education for the guardians of the ideal state.

Legacy

Plato's influence on philosophy, on theology, and on literature is immense. His theory of forms and his conception of philosophy as the pursuit of wisdom shaped the development of Western thought.

His ideas were developed by his successors, challenged by Aristotle, and revived by the Neoplatonists and by later thinkers. The dialogues remain central to the study of philosophy.

The Academy

The Academy, founded by Plato around 387 BC, was an institution for research and teaching that lasted for centuries. It attracted students from throughout the Greek world and became a centre of philosophy and of science.

The Academy emphasised mathematics as a preparation for philosophy, and it is associated with important work in geometry and in astronomy. The inscription over its entrance is said to have warned that no one ignorant of geometry should enter.

The Academy was closed in the sixth century AD, and its tradition influenced the development of the medieval universities.

The Theory of Knowledge

Plato's theory of knowledge holds that knowledge is of the forms, which are eternal and unchanging, and that the objects of sense are the objects of opinion. Knowledge is attained by reason, and it is distinguished from belief by its certainty and by its object.

The theory is developed in the Republic, the Symposium, and other dialogues. It implies that the philosopher, who has knowledge of the forms, is best qualified to rule.

The theory has been criticised for its separation of the world of forms from the world of sense, and for the difficulty of explaining how the two are related. The criticisms were developed by Aristotle and by later philosophers.

The Political Theory

Plato's political theory, developed in the Republic and in the Laws, examines the nature of justice and the organisation of the state. The Republic presents the ideal state, ruled by philosopher-kings, in which each class performs its proper function.

The Laws, written later, presents a more practical constitution, based on the rule of law and on a mixed constitution. It reflects Plato's experience and his reflection on the failure of the ideal state.

Plato's political theory has been interpreted in many ways, and it raises questions about the relation between knowledge and power and about the limits of the state.

The Dialogues and Their Influence

The dialogues are literary as well as philosophical works, and they use character, setting, and drama to explore philosophical questions. They established the dialogue as a form of philosophical writing and influenced the development of the essay.

Plato's influence on philosophy, on theology, and on literature is immense. His ideas shaped the development of Neoplatonism, of Christian theology, and of the philosophy of the Renaissance and of the modern period.

Summary

Plato is one of the founders of Western philosophy, and his dialogues are among its most influential works. His theory of forms, his political theory, and his conception of philosophy shaped the development of thought for more than two millennia.

See also

• Socrates
• Aristotle
• Ancient Greek philosophy