埶 here is said to be an older form of 勢; Sun Tzŭ, however, would seem to have used the former in the sense of “circumstances.” The fuller title 兵勢 is found in the T‘u Shu and the modern text. Wang Hsi expands it into 積勢之變 “the application, in various ways, of accumulated power;” and Chang Yü says: 兵勢以成然後任勢以取勝 “When the soldiers’ energy has reached its height, it may be used to secure victory.”
1. Sun Tzŭ said: The control of a large force is the same principle as the control of a few men: it is merely a question of dividing up their numbers.
That is, cutting up the army into regiments, companies, etc., with subordinate officers in command of each. Tu Mu reminds us of Han Hsin’s famous reply to the first Han Emperor, who once said to him: “How large an army do you think I could lead?” “Not more than 100,000 men, your Majesty.” “And you?” asked the Emperor. “Oh!” he answered, “the more the better” (多多益辦耳). Chang Yü gives the following curious table of the subdivisions of an army: — 5 men make a 列; 2 列 make a 火; 5 火 make a 隊; 2 隊 make a 官; 2 官 make a 曲; 2 曲 make a 部; 2 部 make a 校; 2 校 make a 裨; 2 裨 make a 軍. A 軍 or army corps thus works out at 3200 men. But cf. III. § 1, note. For 曲, see I. § 10. It is possible that 官 in that paragraph may also be used in the above technical sense.
2. Fighting with a large army under your command is nowise different from fighting with a small one: it is merely a question of instituting signs and signals.