The proximity of an army causes prices to go up; and high prices cause people's substance to be drained away. When their substance is drained away, they will be afflicted by heavy exactions. With this loss of substance and exhaustion of strength, the homes of the people will be stripped bare, and their incomes dissipated.

If ignorant both of your enemy and yourself, you are certain to be in peril.

So there are five ways of knowing who will win. Those who know when to fight and when not to fight are victorious. Those who discern when to use many or few troops are victorious. Those whose upper and lower ranks have the same desire are victorious.

One whose troops repeatedly congregate in small groups here and there, whispering together, has lost the masses. One who frequently grants rewards is in deep distress. One who frequently imposes punishments is in great difficulty. One who is at first excessively brutal and then fears the masses is the pinnacle of stupidity.

When the enemy is relaxed, make them toil. When full, starve them. When settled, make them move.

In the practical art of war, the best thing of all is to take the enemy's country whole and intact; to shatter and destroy it is not so good.

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