The fable The Wolf of Zhongshan has been attributed to various authors from the Tang, Song, and Ming dynasties, but its plot remains simple and consistent.
Master Dongguo, a pedantic teacher and follower of Mohism, was always ready to help anyone in distress, regardless of who they were or the circumstances. One day, while traveling through Zhongshan Mountain, he encountered a wounded wolf being pursued by the hunting party of Viscount Zhao Jianzi. Cornered, the wolf glibly and fawningly begged for help. Seeing a chance to practice the Mohist doctrine of "universal fraternity," Master Dongguo risked the nobleman's displeasure. He emptied his book bag and hid the wolf inside. When the Viscount arrived and enquired about the fleeing wolf, Master Dongguo lied, claiming he had seen nothing unusual. The hunters galloped away.
However, once freed from the bag, the wolf revealed its true nature. It declared it was hungry and, since the master had been kind enough to help once, he should complete the deed by allowing himself to be eaten. The wolf also claimed it had nearly been suffocated in the bag, giving it another reason to avenge itself. Terrified, Master Dongguo fled.
An old man leaning on a staff approached and asked what was happening. After hearing both sides, he was asked to make a judgment. After a moment's thought, the old man said, "Mister Wolf should return to the bag. If he was truly tormented inside, then Master Dongguo should be eaten."
The wolf climbed back into the bag, which was tied up as before.
"What are you waiting for?" the old man asked Dongguo. "Why don't you kill him now?"
Only then did Master Dongguo wake up to reality. The wolf was put to death.
This fable is so well-known in China that "Master Dongguo" has become a synonym for a pedantic person, and the "Wolf of Zhongshan" for an ingrate. Handicrafts based on this story serve as constant reminders that the incorrigibly wicked cannot be appeased.