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.

Every wicked man is in ignorance as to what he ought to do, and from what to abstain, and it is because of error such as this that men become unjust and, in a word, wicked.

The majority of mankind would seem to be beguiled into error by pleasure, which, not being really a good, yet seems to be so. So that they indiscriminately choose as good whatsoever gives them pleasure, while they avoid all pain alike as evil.

Those who assert that the mathematical sciences say nothing of the beautiful or the good are in error. For these sciences say and prove a great deal about them; if they do not expressly mention them, but prove attributes which are their results or definitions, it is not true that they tell us nothing about them. The chief forms of beauty are order and symmetry and definiteness, which the mathematical sciences demonstrate in a special degree.