The wise man knows of all things, as far as possible, although he has no knowledge of each of them in detail

No one who desires to become good will become good unless he does good things.

A friend of everyone is a friend of no one

Since the branch of philosophy on which we are at present engaged differs from the others in not being a subject of merely intellectual interest — I mean we are not concerned to know what goodness essentially is, but how we are to become good men, for this alone gives the study its practical value — we must apply our minds to the solution of the problems of conduct.

Friendship is essentially a partnership.

The vices respectively fall short of or exceed what is right in both passions and actions, while virtue both finds and chooses that which is intermediate.

The investigation of the truth is in one way hard, in another easy. An indication of this is found in the fact that no one is able to attain the truth adequately, while, on the other hand, no one fails entirely, but everyone says something true about the nature of all things, and while individually they contribute little or nothing to the truth, by the union of all a considerable amount is amassed.