20. But if neither time nor place be known, then the left wing will be impotent to succour the right, the right equally impotent to succour the left, the van unable to relieve the rear, or the rear to support the van. How much more so if the furthest portions of the army are anything under a hundred li apart, and even the nearest are separated by several li!
The Chinese of this last sentence is a little lacking in precision, but the mental picture we are required to draw is probably that of an army advancing towards a given rendezvous in separate columns, each of which has orders to be there on a fixed date. If the general allows the various detachments to proceed at haphazard, without precise instructions as to the time and place of meeting, the enemy will be able to annihilate the army in detail. Chang Yü’s note may be worth quoting here: “If we do not know the place where our opponents mean to concentrate or the day on which they will join battle, our unity will be forfeited through our preparations for defence, and the positions we hold will be insecure. Suddenly happening upon a powerful foe, we shall be brought to battle in a flurried condition, and no mutual support will be possible between wings, vanguard or rear, especially if there is any great distance between the foremost and hindmost divisions of the army.”
21. Though according to my estimate the soldiers of Yüeh exceed our own in number, that shall advantage them nothing in the matter of victory.
Capt. Calthrop omits 以吾度之, and his translation of the remainder is flabby and inaccurate. As Sun Tzŭ was in the service of the 吳 Wu State, it has been proposed to read 吳 instead of 吾 — a wholly unnecessary tampering with the text. Yüeh coincided roughly with the present province of Chehkiang. Li Ch‘üan very strangely takes 越 not as the proper name, but in the sense of 過 “to surpass.” No other commentator follows him. 勝敗 belongs to the class of expressions like 遠近 “distance,” 大小 “magnitude,” etc., to which the Chinese have to resort