Justice was elaborately discussed by Plato’s Socrates in Book Four of The Republic. This part of the book tries to reiterate and answer the challenges raised by Glaucon and Adeimantus in Book Two. The view of justice that Socrates put forward in Book Four is a larger view of justice moving from the individual level to the State.

This paper ought to argue that Socrates provides an adequate account of justice to answer the challenges provided by Adeimantus and Glaucon. The paper will first try to explore the challenges raised by Adeimantus and Glaucon. Then there will be a brief discussion of Socrates response. Finally, there will be an assessment whether or not Socrates’ argument is sufficient to answer Glaucon’s and Adeimantus’ challenges.

Glaucon’s challenge to the view of justice comes at the beginning of Book Two. He asks Socrates whether justice is an instrumental good or an intrinsic good (357a). To elaborate this further, intrinsic good are good in themselves while instrumental good are good only because of its consequences. Socrates suggests that justice falls into both category –both intrinsic and instrumental type of good. Thus, Glaucon further challenge Socrates to prove his point through an illustration.

 Glaucon argue that injustice is beneficial for the doer because it serves instrumental good. On the other hand it is evil. Glaucon believes that people considered it fine to do something evil however they fear that someone will do them evil. Thus, laws were formulated as a covenant or under a social contract to ensure that injustice will not happen in the society. In this sense, Glaucon identifies justice as a lesser evil.

Glaucon further discussed his point by using the story of the Ring of Gyges (359d), whereas there are two rings which can make a person invisible. The just person would not exploit the power of the ring to do injustice while the unjust would greedily use the rings’ power towards his benefits. Accordingly, the just person would not get anything from being just while the unjust would benefit more (360e). Furthermore, Glaucon asserted that the just person would be laugh at and/or would be considered as an idiot while the unjust would be envied from by ordinary individuals (360d).

Adeimantus on the other hand tries to challenge justice on the basis of being desired (362). Adeimantus puts forward that in real life justice and injustice are treated in relation to manipulation of justice. Those who do justice are reputed to be good while those who do otherwise are considered evil. Adeimantus discussed that the unjust can offer and/or do certain rituals and prayers that can fix their misdemeanor in earth.

Adeimantus further argued that there is a possibility that an unjust man appear to be just in front of another and do otherwise, then pray and do rituals about it later on to please the gods. These circumstances, according to Adeimantus, are how justice and injustice is treated by men. Adeimantus concluded that men do just acts unwillingly –only to please the gods and for the sake of good reputation.

Both Adeimantus and Glaucon work under the influence of Thrasymachus argument which holds that justice is the benefit of the stronger (388c). It undermines the fact the injustice is more favorable than justice. At the end, both Adeimantus and Glaucon are not satisfied with the insistent reputation of Socrates. At the end, Adeimantus and Glaucon challenge Socrates to give them practical application and example of justice --to be better than injustice and not just theoretical proof (366e-367b).

Socrates tries to represent the idea of justice by moving from the individual level to the State then back to the individual (368d). In Book Four, Socrates asserts that each man has a natural inclination. For instance there are people who are naturally good in painting or pottery; others are more adept in singing or writing. At the end, Socrates tries to illuminate that if a person is doing injustice if he will stray upon his natural inclination.

Socrates further elaborates that a State must possess four virtues. The first is wisdom which is not just knowledge in itself but wisdom of the whole city (429c). The second virtue is bravery or courage. It is described as being able to stand firm despite pains, desires, pleasures and fears, for the benefit and safety of the whole State (429d).

The third virtue is about temperance which includes the ability to create an agreement or settlement between the worse and the better (430e). Moderation creates harmony for the state which unites the people or bind them together (433). Finally, justice is defined by Socrates as ‘working towards excellence or what one does best’ (433d). He did this by considering a society, one person, says a potter, would not work at his best if he needs to do several other things such as fishing or farming, carpentry, etc.

To this end, Socrates succeeded in maintaining that to be considered as just --a person must do what he does best. It will be unjust for a potter to do fishing but it is just if he creates pots for himself and for others. Specifically, Socrates established that justice is therefore a situation by which ‘everyone in the state is doing his own work and not meddling with others’ (433b).

Glaucon and Adeimantus beg for specific examples and practical application which will prove that justice is something that is good in it self and therefore desirable in itself (367b). Socrates tries to convince them and to show that ‘justice is indeed doing what one does best’. Socrates thinks that by composing the concept of justice in a larger scale it would be better understood by Glaucon an Adeimantus. He magnifies the situation and brings it back to the individual level. He explains his view while constantly asking for Adeimantus approval or disapproval.

Socrates lay down the components of an ideal State and later discussed justice as doing ‘what one does best’. In so doing he give instances wherein doing one does best is good. A merchant would not do well in selling merchandise but is good in exchanging goods, to travel the goods, there must be a sailor, and a merchant will not do well as a sailor. Thus, he arrives in the conclusion that justice or doing ‘what one does best’ is good in itself.

He then proceeds in describing if it is desirable in itself and not merely because of its effect. Naturally a potter would not to well as a farmer because he lacks the needed knowledge for that job. Therefore, it is only natural for a person to desire what he does best and to despise the thing/s which he knew little or nothing at all. Although he did not directly address back into the challenges, Socrates succeeded in undermining the challenges imposed by Glaucon and Adeimantus.


Reeves, CDC. Plato’s Republic. 2004. Hackett Publishing Company.