The main topics of this chapter are how to forestall the enemy by securing the conditions for victory and by setting up a superior situation from which to do battle. Essentially, it is a question of jockeying for advantage. One of the primary tenets of the Sun Zi is enshrined here in the famous dictum that “War is premised upon deception.”
Master Sun said,
In general, the method of waging war is such that the general receives his mandate from the ruler, then assembles the masses of his army, after which he encamps, facing off against the enemy. Nothing is more difficult than the struggle of armies that ensues. The difficulty of the struggle of armies lies in taking the circuitous as straight, in taking what is troublesome to be advantageous.
Therefore,
take a circuitous route to reach the enemy, tempt him with advantages. Though I set out after him, I reach my destination before him. This is the planning of one who knows how to make the circuitous straight.1
Therefore,
the struggle of armies may be advantageous, but it may also be dangerous. If one commits his entire army to the struggle for advantage, he will not attain it. If one abandons all but the light components of his army in the struggle for advantage, he will forfeit his heavy equipment wagons and grain carts.
For this reason,
if he has his men roll up their armor and rush forward, not stopping day or night and doing double stages in a forced march, traveling a hundred tricents in the struggle for advantage, the generals of his three armies will be captured. Those who are vigorous will arrive first, while those who are weary will come along later, with the result that only one-tenth of the men will reach their destination. If one has his men travel fifty tricents in the contestation of advantage, the general of his upper army will fall, and the result will be that only half of his men will reach their destination. If one has his men travel thirty tricents in the struggle for advantage, two-thirds of them will reach their destination.2
For this reason,
if an army has no heavy equipment wagons, it will lose; if it has no grain supplies, it will lose; and if it has no provisions, it will lose.
Therefore,
he who does not know the intentions of the feudal lords should not enter into diplomatic associations with them; he who does not know the forms of the mountains and forests, the precipices and obstacles, the marshes and swamps should not march his army. He who does not employ local guides will not be able to gain the advantages of the terrain.
Therefore,
war is premised upon deception, motivated by advantage, and modified by dividing and joining.
Therefore,
his armies may be swift as the wind, calm as a forest, raging as a fire, immobile as a mountain, unfathomable as the darkness, volatile as thunder and lightning. When pillaging villages, divide the spoils among the masses; when expanding one’s territory, divide the benefits. Ponder and weigh before moving.
He who is the first to know the planning of how to make the circuitous straight will be victorious.3 This is the method of the struggle of armies.
In the Army Administration4 it says, “In battle words cannot be heard, therefore gongs and drums are used; hand signals cannot be seen, therefore flags and banners are employed.” Gongs, drums, flags, and banners are the means whereby the eyes and ears of men are unified. Once one’s men are concentrated as one, the brave will not go forward alone, and the cowardly will not retreat alone. This is the method of using the masses.
Therefore,
in night battles fire and drums are more often used; in day battles flags and banners are often used. These are the means whereby adjustments are made for the eyes and ears of one’s men.
Therefore,
the three armies can be robbed of their spirit, the general can be robbed of his resolve.5
For this reason,
in the morning an army’s spirit is keen, by midday it begins to slacken, and by evening it is depleted.6
Therefore,
he who is skilled at waging war avoids the enemy army when it is in keen spirit and strikes when its spirit slackens and is depleted—this is how to control morale. Confront chaos with control; confront clamor with quietude—this is how to control the heart. Confront those who have come from a distance with one’s own forces nearby;7 confront those who have toiled with those who are rested; confront those who are hungry with those who are full—this is how to control strength. Do not challenge flags8 that are well ordered; do not strike at formations that are well aligned—this is how to control change.
Therefore,
the method of waging war holds thus: do not face an enemy who occupies the heights; do not oppose an enemy whose back is against a hill; do not follow an enemy who feigns retreat; do not attack soldiers who are in keen spirits; do not swallow troops that the enemy offers as bait; do not intercept an army that is returning home; be sure to leave an opening for an army that is surrounded;9 do not press a desperate foe. This is the method of waging war.