Music has the power of producing a certain effect on the moral character of the soul, and if it has the power to do this, it is clear that the young must be directed to music and must be educated in it.
Demonstration is also something necessary, because a demonstration cannot go otherwise than it does, ... And the cause of this lies with the primary premises/principles.
Thus it is thought that justice is equality; and so it is, but not for all persons, only for those that are equal. Inequality also is thought to be just; and so it is, but not for all, only for the unequal. We make bad mistakes if we neglect this for whom when we are deciding what is just. The reason is that we are making judgements about ourselves, and people are generally bad judges where their own interests are involved.
Of the modes of persuasion furnished by the spoken word there are three kinds. The first kind depends on the personal character ofthe speaker; the second on putting the audience into a certain frame of mind; the third on the proof, provided by the words of the speech itself.
Happiness is something final and complete in itself, as being the aim and end of all practical activities whatever .... Happiness then we define as the active exercise of the mind in conformity with perfect goodness or virtue.
What is the highest good in all matters of action? To the name, there is almost complete agreement; for uneducated and educated alike call it happiness, and make happiness identical with the good life and successful living. They disagree, however, about the meaning of happiness.
Anything that we have to learn to do we learn by the actual doing of it; People become builders by building and instrumentalists by playing instruments. Similarily, we become just by performing just acts, temperate by performing temperate ones, brave by performing brave ones.