The aim of education is to make the pupil like and dislike what he ought....The little human animal will not at first have the right responses. It must be trained to feel pleasure, liking, disgust, and hatred at those things which really are pleasant, likable, disgusting, and hateful.

In inventing a model we may assume what we wish, but should avoid impossibilities.

Thus every action must be due to one or other of seven causes: chance, nature, compulsion, habit, reasoning, anger, or appetite.

Something is infinite if, taking it quantity by quantity, we can always take something outside.

[the virtues] cannot exist without Prudence. A proof of this is that everyone, even at the present day, in defining Virtue, after saying what disposition it is [i.e. moral virtue] and specifying the things with which it is concerned, adds that it is a disposition determined by the right principle; and the right principle is the principle determined by Prudence.

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.

We make war that we may live in peace.