It is not sufficient to know what one ought to say, but one must also know how to say it.

A state is an association of similar persons whose aim is the best life possible. What is best is happiness, and to be happy is an active exercise of virtue and a complete employment of it.

The activity of God, which is transcendent in blessedness, is the activity of contemplation; and therefore among human activities that which is most akin to the divine activity of contemplation will be the greatest source of happiness.

It is possible to fail in many ways . . . while to succeed is possible only in one way (for which reason also one is easy and the other difficult - to miss the mark easy, to hit it difficult).

Aristotle said: "Evil brings men together."

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

Quid quid movetur ab alio movetur"(nothing moves without having been moved).