If ignorant both of your enemy and yourself, you are certain to be in peril.
Know the enemy and know yourself.
It is said that if you know your enemies and know yourself, you will not be imperiled in a hundred battles; if you do not know your enemies but do know yourself, you will win one and lose one; if you do not know your enemies nor yourself, you will be imperiled in every single battle.
To capture an enemies army is better than to destroy it.
Fierce language and pretentious advances are signs that the enemy is about to retreat.
Ponder and deliberate before you make your move. He will conquer who has learned the artifice of deviation. Such is the art of maneuvering.