《左传·昭公·昭公二十六年》
九月，楚平王死去，令尹子常想要立子西，说： 太子壬年纪小，他的母亲不是正妻，而是王子建所聘的，子西年纪大而喜好善良，立年长就顺于情理，建立善良的国家就得治。
九月，楚平王卒。令尹子常欲立子西，曰： 大子壬弱，其母非適也，王子建实聘之。子西长而好善，立长则顺，建善则治。
In September, King Ping of Chu died, and Ling Yin Zi Chang wanted to establish Zi Xi, saying: "Crown Prince Ren is young, and his mother is not the wife, but the princess Jian is hired. Zi Xi is old and good at kindness. Establishing the older is in line with human relations, and establishing the kind is in line with government."