When the enemy is at ease, be able to weary him; when well fed, to starve him; when at rest, to make him move. Appear at places to which he must hasten; move swiftly where he does not expect you.
There is nothing more difficult than tactical maneuvering. The difficult consists in turning the devious into the direct, and misfortune into gain. Thus, to take a long and circuitous route after enticing the enemy out of the way, and though starting after him to contrive to reach the goal before him, shows knowledge of the artifice of deviation.