The Attack by Fire

Chapter 12: Attack by Fire

Sunzi said: There are five types of fire attacks: the first is burning enemy personnel, the second is burning enemy supplies, the third is burning enemy baggage and equipment, the fourth is burning enemy storehouses, and the fifth is burning enemy transport convoys.

To carry out a fire attack, conditions must be met, and incendiary materials must be prepared in advance. Setting fires depends on the weather, and igniting them requires choosing the right day. Weather refers to dry conditions, and the day refers to when the moon is in the positions of the four constellations: Ji, Bi, Yi, and Zhen. Whenever the moon is in these four constellations, it is a day for wind.

In all fire attacks, one must respond according to the variations of the five types of fire: if a fire is set from within the enemy camp, troops should be sent early to support from outside. If the fire has started but the enemy remains calm, wait and observe; do not attack immediately. When the fire is at its fiercest, attack if possible; if not, stop. Fire can also be set from outside the enemy camp, in which case there is no need for an internal response; it can be set as soon as the opportunity is right. When setting fire from upwind, do not attack from downwind. If the wind blows for a long time during the day, it will stop at night. The army must understand the five variations of fire attacks and defend according to weather conditions. Thus, using fire to assist an attack makes it clearly effective; using water to assist an attack can strengthen the offensive. Water can cut off the enemy but cannot seize their matériel like fire can.

Whenever a victory is won or a city is captured, but the gains cannot be consolidated, it is dangerous—this is called "wasteful lingering." Therefore, it is said: a wise sovereign must deliberate carefully, and an excellent general must handle matters prudently. Act only when there is benefit; move only when there is certainty; fight only when there is no other option. A sovereign should not wage war out of anger, nor should a general engage in battle out of wrath. Act when it serves the nation's interests; stop when it does not. Anger can turn back to joy, and wrath can turn back to delight, but a destroyed nation cannot be restored, and the dead cannot be brought back to life. Thus, a wise sovereign is cautious about war, and an excellent general is vigilant about conflict—this is the fundamental principle for securing the state and preserving the army.