He will first of all speak of the nature and origin of justice; secondly, of the manner in which men view justice as a necessity and not a good; and thirdly, he will prove the reasonableness of this view.
'To do injustice is said to be a good; to suffer injustice an evil.

As the evil is discovered by experience to be greater than the good, the sufferers, who cannot also be doers, make a compact that they will have neither, and this compact or mean is called justice, but is really the impossibility of doing injustice.

No one would observe such a compact if he were not obliged.

Let us suppose that the just and unjust have two rings, like that of Gyges in the well-known story, which make them invisible, and then no difference will appear in them, for every one will do evil if he can.

And he who abstains will be regarded by the world as a fool for his pains.