Allegory of the Cave
Glaucon (; ; c. 445 BC – 4th century BC) son of Ariston, was an ancient Athenian and Plato's older brother. He is primarily known as a major conversant with Socrates in the "Republic", and the interlocutor during the Allegory of the Cave. He is also referenced briefly in the beginnings of two dialogues of Plato, the "Parmenides" and "Symposium".