The saying of Protagoras is like the views we have mentioned; he said that man is the measure of all things, meaning simply that that which seems to each man assuredly is. If this is so, it follows that the same thing both is and is not, and is bad and good, and that the contents of all other opposite statements are true, because often a particular thing appears beautiful to some and ugly to others, and that which appears to each man is the measure

Virtue makes us aim at the right end, and practical wisdom makes us take the right means.

Inasmuch as every family is a part of a state, and these relationships are the parts of a family, and the virtue of the part must have regard to the virtue of the whole, women and children must be trained by education with an eye to the constitution, if the virtues of either of them are supposed to make any difference in the virtues of the state. And they must make a difference: for the children grow up to be citizens, and half the free persons in a state are women.

Perhaps here we have a clue to the reason why royal rule used to exist formerly, namely the difficulty of finding enough men of outstanding virtue.

Nature does nothing in vain. Therefore, it is imperative for persons to act in accordance with their nature and develop their latent talents, in order to be content and complete.

Men pay most attention to what is their own: they care less for what is common; or, at any rate, they care for it only to the extent to which each is individually concerned.

What is the highest of all goods achievable by action? ...both the general run of man and people of superior refinement say that it is happiness ...but with regard to what happiness is they differ.