If I determine the enemy's disposition of forces while I have no perceptible form, I can concentrate my forces while the enemy is fragmented. The pinnacle of military deployment approaches the formless: if it is formless, then even the deepest spy cannot discern it nor the wise make plans against it.
Spies cannot be usefully employed without a certain intuitive sagacity; They cannot be properly managed without benevolence and straightforwardness; Without subtle ingenuity of mind, one cannot make certain of the truth of their reports; Be subtle! be subtle! and use your spies for every kind of warfare; If a secret piece of news is divulged by a spy before the time is ripe, he must be put to death together with the man to whom the secret was told.
To perceive victory when it is known to all is not really skilful... It does not take much strength to lift a hair, it does not take sharp eyes to see the sun and moon, it does not take sharp ears to hear the thunderclap.
Be extremely subtle, even to the point of formlessness. Be extremely mysterious, even to the point of soundlessness. Thereby you can be the director of the opponent's fate.
From a position of this sort, if the enemy is unprepared, you may sally forth and defeat him. But if the enemy is prepared for your coming, and you fail to defeat him, then, return being impossible, disaster will ensue.
For the wise man delights in establishing his merit, the brave man likes to show his courage in action, the covetous man is quick at seizing advantages, and the stupid man has no fear of death.
Those who are victorious plan effectively and change decisively. They are like a great river that maintains its course but adjusts its flow...they have form but are formless. They are skilled in both planning and adapting and need not fear the result of a thousand battles: for they win in advance, defeating those that have already lost.
He who knows things, and in fighting puts his knowledge into practice, will win his battles. He who knows them not, nor practices them, will surely be defeated.
Do not press an enemy at bay. Prince Fu Ch'ai said: "Wild beasts, when at bay, fight desperately. How much more is this true of men! If they know there is no alternative, they will fight to the death.