Cephalus Definition Of Justice In Plato's Republic

Plato wrote the Republic in 380 BC. The first book of Plato’s Republic is concerned with justice. What is justice and why should one behave justly are two questions which Socrates and his interlocutors attempt to answer.

First Law of Justice:

The first definition of justice is proposed by Cephalus. Cephalus is an old, wise, and very wealthy man. He provides colossal insight into old age. He says that as one turns older, the outbursts relax and one feels as if he has escaped from a mad and furious beast, and that one experiences a sense of calm and freedom. Cephalus also asserts that the greatest benefit his wealth has conferred upon him is that he never needed to intentionally or unintentionally deceive another man.For when a man nears the end of his life and considers his past infractions, he begins to fear the potential punishment he will suffer in the afterlife. Cephalus concludes that justice is paying debts and telling the truth.

Socrates refutes Cephalus’ definition of justice by posting several instances in which it is not just to tell the truth or to pay one's debts. For example, it is not just to return weapons, entrusted to your care, to a friend who is not in his right senses. Furthermore, if a friend who is not in his right senses approaches you and enquires where another man is, so that

Some laws command citizens to behave contrary to the interest of the stronger. If justice is merely obeying laws then justice is not always the interest of the stronger.

Thrasymachus counters that when rulers pass laws contrary to their interest then they are not the stronger at that point in time. Thrasymachus uses an analogy of a mathematician. When a mathematician makes a mistake while calculating, he is not a mathematician insofar as the name implies at that time, when he airs his skill fails him and he is not a