From The Art of War by Sun Tzu
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Thus, one who is skilled at making the enemy move does so by creating a situation, according to which the enemy will act. He entices the enemy with something he is certain to want. He keeps the enemy on the move by holding out bait and then attacks him with picked troops.
How subtle and insubstantial, that the expert leaves no trace. How divinely mysterious, that he is inaudible. Thus, he is master of his enemy's fate. His offensive will be irresistible if he makes for his enemy's weak positions; he cannot be overtaken when he withdraws if he moves swiftly.
When I wish to give battle, my enemy, even though protected by high walls and deep moats, cannot help but engage me, for I attack a position he must relieve. When I wish to avoid battle, I may defend myself simply be drawing a line on the ground; the enemy will be unable to attack me because I divert him from going where he wishes.
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Therefore, analyze the enemy's plans so that you will know his shortcomings as strong points. Agitate him in order to ascertain the pattern of his movement. Lure him out to reveal his dispositions and ascertain his position. Launch a probing attack in order to learn where his strength is abundant and where deficient. The ultimate in disposing one's troops is to conceal them without ascertainable shape. Then the most penetrating spies cannot pry nor can the wise lay plans against you. It is according to the situations that plans are laid for victory, but the multitude does not comprehend this. Although everyone can see the outward aspects, none understands how the victory is achieved. Therefore, when a victory is won, one's tactics are not repeated. One should always respond to circumstances in an infinite variety of ways.
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