Of actions some aim at what is necessary and useful, and some at what is honorable. And the preference given to one or the other class of actions must necessarily be like the preference given to one or other part of the soul and its actions over the other; there must be war for the sake of peace, business for the sake of leisure, things useful and necessary for the sake of things honorable.
All men naturally desire knowledge. An indication of this is our esteem for the senses; for apart from their use we esteem them for their own sake, and most of all the sense of sight. Not only with a view to action, but even when no action is contemplated, we prefer sight, generally speaking, to all the other senses. The reason of this is that of all the senses sight best helps us to know things, and reveals many distinctions.
Excellence or virtue is a settled disposition of the mind that determines our choice of actions and emotions and consists essentially in observing the mean relative to us ... a mean between two vices, that which depends on excess and that which depends on defect.
Men are divided between those who are as thrifty as if they would live forever, and those who are as extravagant as if they were going to die the next day.
Men agree that justice in the abstract is proportion, but they differ in that some think that if they are equal in any respect they are equal absolutely, others that if they are unequal in any respect they should be unequal in all. The only stable principle of government is equality according to proportion, and for every man to enjoy his own.
It makes no difference whether a good man has defrauded a bad man, or a bad man defrauded a good man, or whether a good or bad man has committed adultery: the law can look only to the amount of damage done.