Fighting with a large army under your command is nowise different from fighting with a small one: it is merely a question of instituting signs and signals.

The enemy's spies who have come to spy on us must be sought out, tempted with bribes, led away and comfortably housed. Thus they will become double agents and available for our service. It is through the information brought by the double agent that we are able to acquire and employ local and inward spies. It is owing to his information, again, that we can cause the doomed spy to carry false tidings to the enemy.

In the tumult and uproar, the battle seems chaotic, but there is no disorder, the troops appear to be milling about in circles but cannot be defeated.

Invincibility depends on one's self; the enemy's vulnerability on him.

When the common soldiers are too strong and their officers too weak, the result is insubordination. When the officers are too strong and the common soldiers too weak, the result is collapse.

A kingdom that has once been destroyed can never come again into being; nor can the dead ever be brought back to life.

He who is not sage and wise, humane and just, cannot use secret agent.s. And he who is not delicate and subtle cannot get the truth out of them.