Plato's Republic

Both Thrasymachus in book one and Glaucon in book two admire unfairness over justice. They both are agreeing with each other point of view, Glaucon just trying to prove the power of unfairness. In book two Glaucon points out that most people class justice among the first group. These peoples view justice as a necessary evil, which Thrasymachus said we allow ourselves to suffer in order to avoid the greater evil that would befall us if we get away with it. Justice stems from human weakness and helplessness and Glaucon said in book two that since we can all suffer from each other's injustices, we make a social contract agreeing to be just to one another. We only suffer under the burden of justice because we know we would suffer worse without it. Justice is not something practiced for its own sake but something one engages in out of fear and weakness.

Thrasymachus in book one admit that the view he is proceeding supports injustice as a good value. In Thrasymachus view, life is seen as a continual competition to get more money, more power, etc and whoever is most successful in the competition has the greatest virtue. Thrasymachus pretense his own definition of justice the interest of the stronger in book one. Thrasymachus unleashes a long diatribe; declaring that injustice benefits the ruler absolutely.

In book two Glaucon ends his speech with an attempt to show that not only do people prefer to be unjust rather than just, but also that it is normal for them to do so. The perfectly unjust life, he argues, is more pleasant than the perfectly just life. In making this claim, he draws two detailed portraits of the just and unjust man. The completely unjust man, who indulges all his urges, is honored and rewarded with wealth. The completely just man, on the other hand, is scorned and wretched.

Glaucon appeals to the Ring of Gyges. According to mythology, this ring has the special power to make its possessor invisible. Glaucon's intention in invoking this magical entity is to argue that even the most just man only behaves as he does because of fear of reprisal. If such a man were able to behave unjustly with impunity, as he could if he were invisible, then he would do so.

It means that Glaucon also believe that justice is the advantage of the stronger. To prove the superiority of injustice as Thrasymachus he used different arguments and observations of fact.