To leave the number of births unrestricted, as is done in most states, inevitably causes poverty among the citizens, and poverty produces crime and faction.

Character may almost be called the most effective means of persuasion.

These virtues are formed in man by his doing the actions ... The good of man is a working of the soul in the way of excellence in a complete life.

No one chooses what does not rest with himself, but only what he thinks can be attained by his own act.

In [the soul] one part naturally rules, and the other is subject, and the virtue of the ruler we maintain to be different from that of the subject; the one being the virtue of the rational, and the other of the irrational part. Now, it is obvious that the same principle applies generally, and therefore almost all things rule and are ruled according to nature.

Nature does nothing in vain.

For the real difference between humans and other animals is that humans alone have perception of good and evil, just and unjust, etc. It is the sharing of a common view in these matters that makes a household and a state.