The Republic by Plato Part 4 Page 42

And if there be any State in which rulers and subjects will be agreed as to the question who are to rule, that again will be our State?

Undoubtedly.

And the citizens being thus agreed among themselves, in which class will temperance be found — in the rulers or in the subjects?

In both, as I should imagine, he replied.

Do you observe that we were not far wrong in our guess that temperance was a sort of harmony?

Why so?

Why, because temperance is unlike courage and wisdom, each of which resides in a part only, the one making the State wise and the other valiant; not so temperance, which extends to the whole, and runs through all the notes of the