If we know that our own men are in a condition to attack, but are unaware that the enemy is not open to attack, we have gone only halfway towards victory. If we know that the enemy is open to attack, but are unaware that our own men are not in a condition to attack, we have gone only halfway towards victory. If we know that the enemy is open to attack, and also know that our men are in a condition to attack, but are unaware that the nature of the ground makes fighting impracticable, we have still gone only halfway towards victory.

Set the troops to their tasks without imparting your designs.

The skillful leader subdues the enemy's troops without any fighting.

The one who figures on victory at headquarters before even doing battle is the one who has the most strategic factors on his side.

All war is based on deception.

Of all those in the army close to the commander, none is more intimate than the secret agent.

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