Dietrich Krohs

The highest form of generalship is to defeat the enemy's plans; the next best is to keep the enemy's forces divided; the next best is to attack the enemy's army in the field; and the worst policy is to besiege walled cities.

He who can modify his tactics in relation to his opponent, and thereby succeed in winning, may be called a heaven-born captain.

A general is skillful in attack whose opponent does not know what to defend; and he is skillful in defense whose opponent does not know what to attack.