Attack him where he is unprepared, appear where you are not expected.

Plan for what is difficult while it is easy, do what is great while it is small.

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.

Fierce language and pretentious advances are signs that the enemy is about to retreat.

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.

Someone unfamiliar with the mountains and forests cannot advance [the team]. One who does not employ local guides cannot gain the advantage.

It is the business of a general to be quiet and thus ensure secrecy; upright and just, and thus maintain order.