The soul becomes prudent by sitting and being quiet.

Moral excellence comes about as a result of habit. We become just by doing just acts, temperate by doing temperate acts, brave by doing brave acts.

A promise made must be a promise kept.

Perfect friendship is the friendship of men who are good, and alike in excellence; for these wish well alike to each other qua good, and they are good in themselves.

It is impossible, or not easy, to alter by argument what has long been absorbed by habit

A likely impossibility is always preferable to an unconvincing possibility.

A young man is not a proper hearer of lectures on political science; for he is inexperienced in the actions that occur in life, but its discussions start from these and are about these; and, further, since he tends to follow his passions, his study will be vain and unprofitable, because the end that is aimed at is not knowledge but action. And it makes no difference whether he is young in years or youthful in character.