He who knows his enemy and himself well will not be defeated easily.

When the thunderclap comes, there is no time to cover the ears.

Ground which can be abandoned but is hard to re-occupy is called entangling.

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.

Those skilled in attack move as from above the nine-fold heavens. Thus they are capable both of protecting themselves and of gaining complete victory.

As water shapes its flow in accordance with the ground, so an army manages its victory in accordance with the situation of the enemy.

Apparent confusion is a product of good order; apparent cowardice, of courage; apparent weakness, of strength.