IX. Moving the Army

Sun Tzu said: In general, in positioning the army and observing the enemy: to cross mountains, keep close to the valleys; face the open, sunny side and take the heights; do not climb to fight an enemy above. This is positioning an army in the mountains. Having crossed a river, move well away from it. When the invader crosses a river to come on, do not meet him in the water; let half his army cross and then strike, to advantage. One who wants to fight should not meet the invader close by the water. Face the open, sunny side and take the heights; do not face upstream against the current. This is positioning an army on rivers.

In crossing salt marshes, simply get across quickly and do not linger. If the armies meet in the middle of a salt marsh, keep close to water and grass, with a grove of trees at the back. This is positioning an army in salt marshes. On level ground, take a position that is easy, with high ground on the right and at the back, death in front and life behind. This is positioning an army on level ground. These four advantageous positions are how the Yellow Emperor defeated the four emperors.¹

In general, an army likes high ground and dislikes low, values the sunny side and scorns the shady. Keep where the men can be nourished and occupy firm ground, and the army will be free of the hundred diseases. This is called certain victory. On hills and embankments, always occupy the sunny side, with the slope on the right and at the back. This is the advantage for the troops and the help of the ground. When it has rained upstream and the water comes flowing down, those who want to ford must wait until it settles.

Wherever the ground has steep-walled ravines, Heaven’s Wells, Heaven’s Prisons, Heaven’s Nets, Heaven’s Pits, or Heaven’s Cracks, leave quickly and do not go near. We keep away from them and let the enemy approach them; we face them and let the enemy have them at his back. If beside the army there are passes and defiles, ponds and pools, reeds and rushes, small woods, or dense undergrowth, search them carefully and repeatedly, for these are where ambushers and spies lie hidden.

When the enemy is near and quiet, he is relying on a strong position. When he is far off and challenges us to battle, he wants us to advance. When he has camped on easy ground, it is because that is to his advantage. When the trees move, he is coming. When there are many screens set up in the grass, he means to mislead us. When birds rise, there is an ambush. When beasts take fright, a surprise attack is coming. When dust rises high and in a sharp column, chariots are coming; when it is low and spread wide, infantry are coming; when it is scattered in strands, they are gathering firewood; when it is thin and comes and goes, they are making camp.

When his envoys speak humbly while he makes preparations, he will advance. When their words are strong and he drives forward as if to attack, he will retreat. When light chariots come out first and take position on the flanks, he is forming for battle. When he asks for peace with no prior agreement, he has a plot. When his men run about and set out the troops in ranks, he has fixed a time. When some advance and some retreat, he is luring us. When the soldiers stand leaning on their weapons, they are hungry. When those sent to draw water drink first, they are thirsty.

When he sees an advantage and does not advance, he is weary. When birds gather, the camp is empty. When there is shouting at night, he is afraid. When the army is in turmoil, the general lacks authority. When flags and banners shift about, there is disorder. When the officers are angry, the men are exhausted. When they kill their horses and eat the meat, the army has no grain. When they hang up their water jars and do not go back to their quarters, they are desperate. When the general speaks to his men slowly and softly, in a coaxing murmur, he has lost the men. Frequent rewards mean he is at the end of his resources; frequent punishments mean he is in distress. To be harsh at first and then fear one’s own men is the height of incompetence. When envoys come with gifts and apologies, he wants a respite.

When the enemy’s troops come on in anger and face us, but for a long time neither join battle nor withdraw, watch them with great care. In war, more is not better. Only do not advance rashly; it is enough to concentrate strength, size up the enemy, and take him. One who has no forethought and takes the enemy lightly is sure to be captured by others.

If the soldiers are punished before they have grown attached, they will not submit, and if they do not submit, they are hard to use. If they are attached but punishments are not carried out, they cannot be used. So unite them with civility and bring them into line with martial discipline. This is called being sure to prevail. If orders are consistently carried out in instructing the people, the people will submit; if orders are not consistently carried out in instructing the people, the people will not submit. When orders are consistently carried out, the general and the men are of one accord.

Notes

1. 1. The Yellow Emperor was a legendary sovereign of earliest antiquity; the “four emperors” were said to be rulers of the four quarters whom he overcame.