For though we love both the truth and our friends, piety requires us to honor the truth first.

All teaching and all intellectual learning come about from already existing knowledge.

The activity of happiness must occupy an entire lifetime; for one swallow does not a summer make.

It is clear that those constitutions which aim at the common good are right, as being in accord with absolute justice; while those which aim only at the good of the rulers are wrong.

We, on the other hand, must take for granted that the things that exist by nature are, either all or some of them, in motion.

Take the case of just actions; just punishments and chastisements do indeed spring from a good principle, but they are good only because we cannot do without them - it would be better that neither individuals nor states should need anything of the sort - but actions which aim at honor and advantage are absolutely the best. The conditional action is only the choice of a lesser evil; whereas these are the foundation and creation of good. A good man may make the best even of poverty and disease, and the other ills of life.

All men, or most men, wish what is noble but choose what is profitable; and while it is noble to render a service not with an eye to receiving one in return, it is profitable to receive one. One ought therefore, if one can, to return the equivalent of services received, and to do so willingly; for one ought not to make a man one's friend if one is unwilling to return his favors.