Zai Yu (Chinese: 宰予; Wade–Giles: Tsai Yü; 522–458 BC),courtesy name Ziwo (Chinese: 子我; Wade–Giles: Tzu-wo), commonly known as Zai Wo (Chinese: 宰我; Wade–Giles: Tsai Wo), was a prominent disciple of Confucius, known for his gift in speech. However, Confucius severely criticized him for proposing to shorten the three-year mourning period after the death of a parent.
Zai Yu was a native of the State of Lu. He was considered the most eloquent speaker among Confucius' disciples. However, the only references of him in the Analects were Confucius' criticism of him. In an important discussion of mourning, Zai Yu questioned the necessity for the three-year mourning period after the death of a parent, and suggested a maximum of one year of mourning. Confucius severely criticized Zai Yu, describing him as inhuman. Confucius also criticized him for sleeping during the day, comparing him to rotten wood that cannot be carved (朽木不可雕也). Despite the criticism, he remained one of the Master's close disciples.
According to Sima Qian's Records of the Grand Historian, Zai Yu served as a minister in Linzi, the capital of Qi, and was killed when he was involved in the rebellion of Chen Heng (陳恆) and his clan was exterminated. Sima Qian further says that Confucius was ashamed of Zai Yu's death. However, this account has been questioned by scholars since ancient times, as the Zuozhuan only mentions that Kan Zhi (阚止) was killed in Chen Heng's rebellion. As Kan Zhi was also known by his courtesy name Ziwo, which was identical to that of Zai Yu, Sima Qian may have conflated the two people's stories.