Plato’s Republic focuses on one particular question: is it better to be just or unjust? Thrasymachus introduces this question in book I by suggesting that justice is established as an advantage to the stronger, who may act unjustly, so that the weak will “act justly” by serving in their interests. Therefore, he claims that justice is “stronger, freer, and more masterly than justice” (Plato, Republic 344c). Plato begins to argue that injustice is never more profitable to a person than justice and Thrasymachus withdraws from the argument, granting Plato’s response. Glaucon, however, is not satisfied and proposes a challenge to Plato to prove that justice is intrinsically valuable and that living a just life is always superior. This paper will explain Glaucon’s challenge to Plato regarding the value of justice, followed by Plato’s response in which he argues that his theory of justice, explained by three parts of the soul, proves the intrinsic value of justice and that a just life is preeminent. Finally, it will be shown that Plato’s response succeeds in answering Glaucon’s challenge.
Glaucon begins his argument to Plato by separating goods into three classes. The first class is composed of intrinsic goods that we welcome for our own sake, stripped of their consequences, such as happiness. The second class is the type of good that we like for our own sake as well as its consequences, such as health and knowledge. The third class is an extrinsic good that we desire only for their consequences, such as physical training and medical treatment. Plato believes that justice belongs in the second class of goods that we like because of itself and its consequences, while Glaucon suggests that it belongs in the third class of goods we desire only for their consequences.
Glaucon presents that, “The best is to do injustice without paying the penalty; the worst is to suffer it without being able to take revenge. Justice is a mean between these two extremes” (Plato,...