• Be flexible in your plans. Take the best opportunity as it presents itself.
• Knowledge is power. The aim is to 1. gain it for yourself, and 2. take it away from the enemy.
• If you look easy to crush, your enemy might very well underestimate you and fall into a trap.
• Mess with the enemy. Make him prone to make bad decisions.
• The best strategist wins. Plan way ahead of your opponent.
• The best battle isn't fought.
• The good leader wins without a fight. Takes over cities without siege. Overthrows a kingdom without lengthy operations in the field.
• You always try to make the most optimal move you can. If at some point, the enemy makes a suboptimal move, it is crucial to capitalize on it.

Hence the saying: If you know the enemy and know yourself, you need not fear the result of a hundred battles. If you know yourself but not the enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle.