Gong Shu Ban had completed the construction of Cloud-ladders for Chu and was going to attack Song with them. Mozi heard of it and set out from Qi. He walked ten days and ten nights and arrived at Ying. He saw Gong Shu Ban. The latter asked him what he wanted of him. Mozi said: Some one in the north has humiliated me. I would like to have you kill him. Gong Shu Ban was displeased. Mozi persisted, offering him ten jin. Finally Gong Shu Ban said: "My principle is incompatible with murdering people." Thereupon Mozi rose and bowed twice and spoke: Now, let me explain myself. While in the north I heard you were building ladders to attack Song. Now, of what is Song guilty? The state of Jing has land to spare but is short of people. To destroy what is scarce in order to strive for what is already plenty cannot be said to be wise. Since Song is innocent, to attack it cannot be said to be magnanimous. To fail to make an effort according to what you know cannot be said to be loyal. To make the effort without obtaining (the desired result) cannot be said to be effective. To hold a principle that forbids the killing of few but allows that of many cannot be said to be understanding the fundamental categories. Gong Shu Ban became convinced. Mozi argued further: Then why would you not stop it? Gong Shu Ban said that could not be done as he had already promised the Lord. Mozi said: Why not then present me to the Lord? Gong Shu Ban agreed.
Mozi saw the Lord and said: Suppose there is a man who, putting aside his elegant carriage, desires to steal his neighbour’s shattered sedan; putting aside his embroidery and finery, desires to steal his neighbour’s short jacket; putting aside his meat and grains desires to steal his neighbour’s husks. What kind of a man would this be? The Lord said that he must be suffering from kleptomania. Mozi continued: The land of Jing amounts to five thousand li square while that of Song is only five hundred, this is similar to the contrast between the elegant carriage and the shattered sedan. Jing possesses Yun Meng which is full of rhinoceroses and deer. The fish, tortoises and crocodiles in the Yangtse and the Han Rivers are the richest in the empire. While Song is said to possess not even pheasants, rabbits, or foxes. This is similar to the contrast between meat and grains and husks. In Jing there are tall pines, spruces, cedars and camphor trees, while Song has no tall trees at all. This is similar to the contrast between embroidery and finery and the short jacket. When your ministers and generals set out to attack Song, it seems to me there is the same strategy. I can see, my Lord, you will be violating righteousness to no advantage. The Lord said: "That is all very well. But Gong Shu Ban has already constructed the Cloud-ladders for me, and I must capture Song."
And he turned to Gong Shu Ban. Mozi untied his belt and laid out a city with it, and used a small stick for weapon. Gong Shu Ban set up nine different machines of attack. Mozi repulsed him nine times. Gong Shu Ban was at an end with his machines of attack while Mozi was far from being exhausted in defence. Gong Shu Ban felt embarassed and declared: "I know how I can put you down, but I would not tell." Mozi also said: "I know how you can put me down, but I would not tell." The Lord of Chu asked what it was. Mozi replied: Gong Shuzi’s idea is just to have me murdered. (Apparently,) when I was murdered, Song would be powerless at defence. And she would be subject to your attack. However, my disciples Qin Hua Li and others numbering three hundred are already armed with my implements of defence waiting on the city wall of Song for the bandits from Chu. Though I be murdered, you cannot exhaust (the defence of Song). The Lord of Chu said: "Well, then let us not attack Song any more."
On his way back, Mozi passed through Song. It was raining and he sought shelter in a pass. But the guard of the pass would not let him in. Thus it is said: "The merit of the man who cultivates himself before the spirits is not recognized by the multitude. On the other hand, he who strives in the open is recognized."