" Leonardo da Vinci: And now my friends I know the secret.
Jack: You do?
Leonardo da Vinci: Yes, the secret to happiness is available to all of us, every hour of every day. Young, old, rich, poor — everyone can choose to find happiness in this way.
Annie: How? What's the secret?
Leonardo da Vinci: Curiosity "

― Mary Pope Osborne , Monday with a Mad Genius (Magic Tree House, #38)