3 · Attack by Stratagem

Sun Tzu said: In the operations of war, to take a state whole is best, to destroy it second best; to take an army whole is best, to destroy it second best; to take a battalion whole is best, to destroy it second best; to take a company whole is best, to destroy it second best; to take a squad whole is best, to destroy it second best. Therefore to win a hundred victories in a hundred battles is not the height of excellence; to subdue the enemy's army without fighting is the height of excellence.

Therefore the highest form of warfare is to attack the enemy's plans; the next is to attack his alliances; the next is to attack his army; the lowest is to attack walled cities. Attacking cities is a method used only when there is no alternative. Preparing mantlets and armoured siege-cars and assembling the engines of war takes three months; building earthen ramps against the walls takes another three. If the commander cannot master his impatience and sends his men swarming up the walls like ants, a third of them will be killed and the city still not taken. Such is the calamity of attacking cities.

Therefore one who is skilled in war subdues the enemy's army without fighting, takes his cities without assaulting them, and overthrows his state without prolonged operations. He contends for mastery under heaven by keeping things whole, so that his troops are not worn down and his gains are complete. This is the method of attack by stratagem.

Therefore the rule in war is: with ten times the enemy's strength, surround him; with five times, attack him; with twice, divide him; if equal, you may engage him; if fewer, you may hold him off; if much weaker, you may evade him. For a small force that stubbornly holds its ground will only be captured by a larger one.

The commander is the support of the state. If the support is complete at every point, the state will surely be strong; if the support is defective, the state will surely be weak.

There are three ways in which a ruler can bring misfortune on his army. Not knowing that the army cannot advance, he orders it to advance; not knowing that it cannot retreat, he orders it to retreat. This is called hobbling the army. Not understanding military affairs, he shares in their administration, and the officers are perplexed. Not understanding the exercise of command, he shares in the responsibilities of the commanders, and the officers are filled with doubt. When the army is perplexed and doubtful, trouble from the other lords will come. This is called throwing the army into disorder and handing victory to the enemy.

Therefore there are five ways of knowing who will win. He who knows when he can fight and when he cannot will win. He who understands how to use both large and small forces will win. He whose ranks, high and low, share the same desire will win. He who, prepared himself, waits for an unprepared enemy will win. He whose commander is capable and not interfered with by the ruler will win. These five are the way to know victory.

Therefore it is said: Know the enemy and know yourself, and in a hundred battles you will never be in peril. If you do not know the enemy but know yourself, you will win one and lose one. If you know neither the enemy nor yourself, you will be in peril in every battle.