Knowledge becomes evil if the aim be not virtuous. - Plato

"Knowledge which is acquired under compulsion has no hold on the mind. Therefore do not use compulsion, but let early education be a sort of amusement; you will then be better able to discover the child's natural bent."

"Music is a moral law. It gives soul to the universe, wings to the mind, flight to the imagination, and charm and gaiety to life and to everything."

"Knowledge unqualified is knowledge simply of something learned."

"Life must be lived as play."

"False words are not only evil in themselves, but they infect the soul with evil."