Once, Yan Yuan asked his mentor Confucius why those who are good at swimming or diving can learn how to steer a boat very quickly.
Confucius replied, "It is because good swimmers do not fear the water. Good divers regard even the deepest abyss as mere land and hills. They handle danger with ease and remain undaunted anywhere.
Consider gambling: if a person wagers with clay tiles, he may win with skill. If he wagers with a silver hook, his mind fills with dread. If he wagers with gold, he becomes dizzy with fear. This is because he values worldly possessions too much. Thus, those who overvalue material things inevitably have clumsy thoughts."