an emendation suggested by 李靖 Li Ching. The meaning then would be “He lies in wait with the main body of his troops.”.
21. The clever combatant looks to the effect of combined energy, and does not require too much from individuals.
Tu Mu says: “He first of all considers the power of his army in the bulk; afterwards he takes individual talent into account, and uses each man according to his capabilities. He does not demand perfection from the untalented.”
Hence his ability to pick out the right men and utilize combined energy.
Another reading has 之 instead of 埶. It would be interesting if Capt. Calthrop could tell us where the following occurs in the Chinese: “yet, when and opening or advantage shows, he pushes it to its limits.”
22. When he utilizes combined energy, his fighting men become as it were like unto rolling logs or stones. For it is the nature of a log or stone to remain motionless on level ground, and to move when on a slope; if four-cornered, to come to a standstill, but if round-shaped, to go rolling down.
Ts‘ao Kung calls this 任自然勢 “the use of natural or inherent power.” Capt. Calthrop ignores the last part of the sentence entirely. In its stead he has: “So await the opportunity, and so act when the opportunity arrives” — another absolutely gratuitous interpolation. The T‘ung Tien omits 任.
23. Thus the energy developed by good fighting men is as the momentum of a round stone rolled down a mountain thousands of feet in height. So much on the subject of energy.
The T‘ung Tien omits 善. The chief lesson of his chapter, in Tu Mu’s opinion, is the paramount importance in war of rapid evolutions and sudden rushes. “Great results,” he adds, “can thus be achieved with small forces.”