Quickness is the essence of the war.

Nothing is more difficult than the art of maneuver. What is difficult about maneuver is to make the devious route the most direct and to turn misfortune to advantage.

Of all those in the army close to the commander none is more intimate than the secret agent; of all rewards none more liberal than those given to secret agents; of all matters none is more confidential than those relating to secret operations.

Do not swallow bait offered by the enemy. Do not interfere with an army that is returning home.

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

Victory is the main object in war.

Hence the saying: If you know the enemy and you know yourself, your victory will not stand in doubt; if you now Heaven and you know Earth, you may make your victory complete.