Characters

• Socrates: A philosopher
• Cephalus: A wealthy, old merchant
• Polemarchus: Cephalus’s son
• Thrasymachus: A sophist

Summary

First reading of Plato’s Republic.

Cephalus and Polemarchus

Cephalus’s idea of justice is to speak the truth and repay what one has borrowed. Socrates provides a scenario where the statement isn’t true.

Justice is then thought of as a mean to an end. However, there is no situation where it is the prefered choice. When it is used to achieve an end, one can’t assert he objectively did the right thing.

Thrasymachus

Contrasting to the intuition of goodness that comes from justice, Thrasymachus’s idea of justice is what is advantageous for the stronger, regardless of whether the action is morally good or bad. This is because people are naturally inclined strive for self interest. Furthermore, justice is to obey the rules made by those stronger. If acting in justice benefits another being, that is only because the end goal of the action benefited the actor. With this argument, the actor is being unjust, only that it appears just. Thrasymachus states that injustice gets a person more interests and therefore better than justice.

Socrates argues injustice causes chaos and the individual to lose alliance from both other people and one’s soul. The soul is virtuous when it is just. Therefore justice will lead to a happier life than injustice.