Man by nature wants to know.

Whether we will philosophize or we won't philosophize, we must philosophize.

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.

The happy life is thought to be one of excellence; now an excellent life requires exertion, and does not consist in amusement.

Now that practical skills have developed enough to provide adequately for material needs, one of these sciences which are not devoted to utilitarian ends [mathematics] has been able to arise in Egypt, the priestly caste there having the leisure necessary for disinterested research.

All friendly feelings toward others come from the friendly feelings a person has for himself.

It is not enough to win a war; it is more important to organize the peace.