Socrates' young companions, Glaucon and Adeimantus, continue the argument of Thrasymachus for the sake of furthering the discussion. Socrates believes he has answered Thrasymachus and is done with the discussion of justice. The first book ends in aporia concerning its essence. Polemarchus says justice is 'the art which gives good to friends and evil to enemies.' Thrasymachus proclaims 'justice is nothing else than the interest of the stronger.' Socrates overturns their definitions and says that it is to one's advantage to be just and disadvantage to be unjust. Cephalus defines justice as giving what is owed.
Socrates then asks Cephalus, Polemarchus, and Thrasymachus their definitions of justice.
While visiting the Piraeus with Glaucon, Polemarchus tells Socrates to join him for a romp. ( November 2010) ( Learn how and when to remove this template message) Unsourced material may be challenged and removed. Please help improve this article by adding citations to reliable sources. This section needs additional citations for verification. Plato from Raphael's The School of Athens (1509–1511)
