We must now examine whether just people also live better and are happier than unjust ones. I think it's clear already that this is so, but we must look into it further, since the argument concerns no ordinary topic, but the way we ought to live.
We must infer that all things are produced more plentifully and easily and of a better quality when one man does one thing which is natural to him and does it at the right time, and leaves other things.
For when there are no words, it is very difficult to recognize the meaning of the harmony and rhythm, or to see any worldly object is imitated by them.
But that we shall be better and braver and less helpless if we think that we ought to enquire, than we should have been if we indulged in the idle fancy that there was no knowing and no use in seeking to know what we do not know; - that is a theme upon which I am ready to fight, in word and deed, to the utmost of my power.
What is at issue is the conversion of the mind from the twilight of error to the truth, that climb up into the real world which we shall call true philosophy.
Any one who has common sense will remember that the bewilderments of the eyes are of two kinds, and arise from two causes, either from coming out of the light or from going into the light, which is true of the mind's eye, quite as much as of the bodily eye; and he who remembers this when he sees any one whose vision is perplexed and weak, will not be too ready to laugh; he will first ask whether that soul of man has come out of the brighter light, and is unable to see because unaccustomed to the dark, or having turned from darkness to the day is dazzled by excess of light.
When I hear a man discoursing of virtue, or of any sort of wisdom, who is a true man and worthy of his theme, I am delighted beyond measure: and I compare the man and his words, and note the harmony and correspondence of them. And such an one I deem to be the true musician, having in himself a fairer harmony than that of the lyre.
Justice in the individual is now defined analogously to justice in the state. The individual is wise and brave in virtue of his reason and spirit respectively: he is disciplined when spirit and appetite are in proper subordination to reason. He is just in virtue of the harmony which exists when all three elements of the mind perform their proper function and so achieve their proper fulfillment; he is unjust when no such harmony exists.