The enlightened ruler is heedful, and the good general full of caution.
Even the finest sword plunged into salt water will eventually rust.
If ignorant both of your enemy and yourself, you are certain to be in peril.
He who knows when he can fight and when he cannot, will be victorious.
There has never been a protracted war from which a country has benefited.
If you are far from the enemy, make him believe you are near.
