Error is multiform (for evil is a form of the unlimited, as in the old Pythagorean imagery, and good of the limited), whereas success is possible in one way only (which is why it is easy to fail and difficult to succeed - easy to miss the target and difficult to hit it); so this is another reason why excess and deficiency are a mark of vice, and observance of the mean a mark of virtue: Goodness is simple, badness is manifold.

In all things of nature there is something of the marvelous.

Let us be well persuaded that everyone of us possesses happiness in proportion to his virtue and wisdom, and according as he acts in obedience to their suggestion.

It is their character indeed that makes people who they are. But it is by reason of their actions that they are happy or the reverse.

For both excessive and insufficient exercise destroy one's strength, and both eating and drinking too much or too little destroy health, whereas the right quantity produces, increases and preserves it. So it is the same with temperance, courage and the other virtues. This much then, is clear: in all our conduct it is the mean that is to be commended.

The science that studies the supreme good for man is politics.

All men by nature desire knowledge.