2 · Waging War

Sun Tzu said: In the operations of war, where there are a thousand swift chariots, a thousand armoured wagons and a hundred thousand mailed troops, with provisions to be carried a thousand li, the expenses at home and at the front, the entertainment of envoys, materials such as glue and lacquer, and the upkeep of chariots and armour will amount to a thousand pieces of gold a day. Only then can an army of a hundred thousand men be raised. In conducting war, what is valued is victory. If it is prolonged, weapons grow blunt and ardour is dampened; if you lay siege to cities, your strength will be exhausted; if the army is kept long in the field, the resources of the state will not suffice. When weapons are blunted, ardour dampened, strength exhausted and treasure spent, the other lords will rise to take advantage of your extremity, and then even the wisest will be unable to set matters right. Thus we have heard of clumsy haste in war, but have never seen cleverness linked with long delay. There has never been a protracted war from which a state has benefited. Therefore one who does not fully understand the harm of using troops cannot fully understand the profit of using them.

One who is skilled in using troops does not raise a second levy, nor load his supply wagons more than twice. He takes his equipment from his own state but forages on the enemy, and so the army's food will be sufficient.

A state is impoverished by its army when it has to supply it at a distance; supplying an army at a distance impoverishes the people. Where the army is near, prices go up; when prices go up, the people's wealth is drained; when their wealth is drained, they are hard pressed by levies. With strength exhausted and wealth spent, the households in the heart of the country are left empty. Of the people's means, seven tenths are gone; of the government's means — broken chariots and worn-out horses, helmets and armour, bows and arrows, halberds and shields, mantlets, draught oxen and heavy wagons — six tenths are gone.

Therefore a wise commander strives to feed his army off the enemy. One measure of the enemy's provisions is worth twenty of one's own; one picul of his fodder is worth twenty of one's own.

To kill the enemy, rouse your men to anger; to take the enemy's goods, let them have their share as reward. Therefore, in chariot fighting, when ten or more chariots have been taken, reward the one who took the first. Replace the enemy's flags and banners with your own, mix the captured chariots with yours and use them, and treat the captured soldiers well and look after them. This is called conquering the enemy and growing stronger.

Therefore what is valued in war is victory, not prolonged operations. The commander who understands war is the arbiter of the people's fate, the master of the state's safety or peril.