Around 440 BC, Mozi was about 29 years old. Chu State was preparing to attack the Song State, and invited the famous craftsman Lu Ban to make ladders and other siege equipment. Mozi was giving lectures in his hometown at that time, and he was very anxious after hearing the news. On the one hand, I arranged for my eldest disciple to lead 300 elite disciples to help Song Shoucheng; While personally dissuading the king of Chu. Mozi hurried and walked day and night, and he didn't care if his shoes were worn out. Ten days later, he arrived at Guoduying (now Xuancheng, Hubei) in Chu State. After arriving in Du Ying, Mozi first found Lu Ban and advised him to stop making weapons to attack the Song Dynasty. Lu Ban introduced Mozi to the King of Chu. Mozi said: "Now a man has lost his decorated carriage, but he wants to steal his neighbor's broken car;" Who is this man who lost his gorgeous clothes and tried to steal his neighbor's coarse cloth? The king of Chu replied without thinking, "This man must be impatient with stealing!" " Mozi took the opportunity to say to the king of Chu, "Fiona Fang, a state of Chu, is five thousand miles away, with fertile land and rich products, while the territory of Song is narrow and the resources are poor. Comparing the two is like floating and rags, splendid and rags. The king attacked the state of Song. Isn't that like a thief? If you attack the Song Dynasty, the king will lose his virtue and fail. "The king of Chu refused to give up his decision to attack the Song Dynasty on the grounds that Lu Ban built siege equipment. Mozi also said to the king of Chu: "The siege equipment made by Luban is not a magic weapon to win. If the king doesn't believe me, let me practice the offensive and defensive warfare face to face with him and see how I can crack it! "After the consent of the king of Chu, Mozi used a belt to simulate the city wall, used sawdust to represent various instruments, and practiced various offensive and defensive battles with Lu Ban. Lu Ban organized nine attacks and was defeated by Mozi nine times. Luban's siege equipment was exhausted, and Mozi's guarding equipment was left. After giving up, Lu Ban deliberately said, "I know how to hit you, but I won't say anything." Mozi replied, "I won't tell you how you beat me." The king of Chu was puzzled and asked, "What are you talking about?" "Mozi said sternly," he thought that if he killed me, the state of Song would be lost. However, I have arranged that my eldest disciple Yin Xili can take the place of me, take the equipment made by Mohism to command the guarding city, and stand by with the soldiers and civilians of Song State! Even if you kill me, you can't win! " These words completely dispelled the idea that the king of Chu attacked the Song Dynasty. Knowing that there was no hope of winning, the king of Chu was forced to give up his plan to attack the state of Song. This is the allusion of Mo Zhai's speech to prevent Chu from attacking Song Dynasty.