A man becomes a friend whenever being loved he loves in return.

... a science must deal with a subject and its properties.

Metaphysics involves intuitive knowledge of unprovable starting-points concepts and truth and demonstrative knowledge of what follows from them.

For imitation is natural to man from his infancy. Man differs from other animals particularly in this, that he is imitative, and acquires his rudiments of knowledge in this way; besides, the delight in it is universal.

The rattle is a toy suited to the infant mind, and education is a rattle or toy for children of larger growth.

Good laws, if they are not obeyed, do not constitute good government.

There are branches of learning and education which we must study merely with a view to leisure spent in intellectual activity, and these are to be valued for their own sake; whereas those kinds of knowledge which are useful in business are to be deemed necessary, and exist for the sake of other things.