A child becomes an adult when he realizes that he has a right not only to be right but also to be wrong.

Boredom is the feeling that everything is a waste of time; serenity, that nothing is.

In the animal kingdom, the rule is, eat or be eaten; in the human kingdom, define or be defined.

Knowledge is gained by learning; trust by doubt; skill by practice; love by love.

Happiness is an imaginary condition formerly often attributed by the living to the dead, now usually attributed by adults to children, and by children to adults.