One day, Confucius stood alone in the courtyard and saw his son Kong Li walking respectfully with hasty steps. He called him and asked, "Have you learned The Book of Songs?" Kong Li replied, "Not yet." Confucius then said, "If you don't learn The Book of Songs, you can't talk with others properly." So Kong Li went back to learn The Book of Songs seriously. A few days later, when Kong Li passed the courtyard, he was again stopped by Confucius and asked, "Have you learned The Book of Rites?" Kong Li replied, "Not yet." Confucius said, "If you don't learn The Book of Rites, your character cannot be established." So Kong Li went back to learn The Book of Rites.