Ning Wuzi, whose surname was Ning and given name was Yu, was posthumously honored as "Wuzi," hence called Ning Wuzi. He was a native of the State of Wey during the Spring and Autumn Period and served as a Grand Master under Duke Wen and Duke Cheng of Wey. When Duke Wen of Wey governed with the Dao (Way), all capable individuals could find channels to display their talents. In such a peaceful era, Ning Wuzi showed no remarkable achievements or merits, suggesting his wisdom was at a level ordinary people could reach. After Duke Wen, Duke Cheng of Wey ascended the throne, and Ning Wuzi continued as a Grand Master. Duke Cheng of Wey was unprincipled, was attacked by the State of Jin, ultimately lost Wey, and fled successively to Chu and Chen, finally being captured by the Marquis of Jin. During Duke Cheng's most difficult times, the clever and crafty officials in the court only sought self-preservation and were unwilling to go to his rescue to avoid disaster. Only Ning Wuzi, with utmost loyalty and devotion, stepped forward, maneuvered among the parties, exerted all his efforts, and braved dangers, ultimately preserving Duke Cheng. Therefore, Confucius commented that Ning Wuzi's intelligence could be matched by others, but his foolishness could not.