The shape of the heaven is of necessity spherical; for that is the shape most appropriate to its substance and also by nature primary.

In everything, it is no easy task to find the middle.

A constitution is the arrangement of magistracies in a state.

In the first place, then, men should guard against the beginning of change, and in the second place they should not rely upon the political devices of which I have already spoken invented only to deceive the people, for they are proved by experience to be useless.

The body is most fully developed from thirty to thirty-five years of age, the mind at about forty-nine.

The chief forms of beauty are order and symmetry and definiteness, which the mathematical sciences demonstrate in a special degree.

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.