born 1501 died 1570 Korean religious leader, the foremost Korean Confucian. He helped shape the character of Korean Confucianism through his creative interpretation of Zhu Xi's teaching. His To Become a Sage: The Ten Diagrams on Sage Learning, an aid for educating the king, offered a depiction of all the major concepts in Song-dynasty learning. He elevated the level of Confucian dialogue to a new height of intellectual sophistication through his correspondence with Ki Taesung (1527-72). In their so-called four-seven debate, they discussed the relationship between Mencius's four basic human feelings (commiseration, shame, modesty, right versus wrong) and seven emotions