If your enemy is secure at all points, be prepared for him. If he is in superior strength, evade him. If your opponent is tempermental, seek to irritate him. Pretend to be weak, that he may grow arrogant. If he is taking his ease, give him no rest. If his forces are united, separate them. If sovereign and subject are in accord, put division between them. Attack him where he is unprepared, appear where you are not expected.

Spies are a most important element in water, because on them depends an army's ability to move.

The control of a large force is the same principle as the control of a few men: it is merely a question of dividing up their numbers.

If the enemy leaves a door open, you must rush in.

Those who are victorious plan effectively and change decisively. They are like a great river that maintains its course but adjusts its flow.

When you surround an army, leave an outlet free. Do not press a desperate foe too hard.

Without local guides, your enemy employs the land as a weapon against you.