Cao Shang of the State of Song went to the State of Qin as an envoy. He set out with only a few carriages provided by Song but returned with one hundred carriages bestowed by the King of Qin, a reward for his skillful flattery.
He visited Zhuangzi complacently and boasted, "My strength lies in persuading the king of a powerful state, fulfilling the mission assigned by my own sovereign, and being followed by a hundred carriages."
Zhuangzi responded in surprise, "I have heard that when the King of Qin summoned doctors to treat his illness, he would reward anyone who licked his hemorrhoids with five carriages. The filthier the treatment, the more carriages one would receive. How could you have obtained so many carriages if you had not licked his hemorrhoids? You had better leave my presence at once."