Why does Plato examine justice in an ideal state in the Republic?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

The Greek philosopher Plato — Plato Plato, marble portrait bust copied from an original of the 4th century bce; in the Capitoline Museums, Rome.

In his work The Republic, Plato examines justice within an ideal state primarily to facilitate his inquiry into individual ethics.1

While the dialogue begins with the personal question, "Why should I be just?", Socrates suggests that justice is difficult to discern in a single person. By examining justice "writ large" in the structure of a city-state, Plato aims to make the concept more visible and easier to analyze.1

Plato argues that political justice exists when each social class—rulers, guardians, and producers—performs its specific role without interference. He then draws an analogy between the state and the individual soul, which is also divided into three parts: reason, spirit, and appetite. Just as political justice is the harmonious functioning of social classes, ethical justice is the internal harmony of the soul, where reason governs the other parts. Thus, the political discussion serves as a framework to demonstrate why being just is in each person's best interest.1