The Art of War by active 6th century B.C. Sunzi

60. Success in warfare is gained by carefully accommodating ourselves

to the enemy’s purpose. [Ts’ao Kung says: "Feign stupidity"—by an appearance of yielding and falling in with the enemy’s wishes. Chang Yu’s note makes the meaning clear: "If the enemy shows an inclination to advance, lure him on to do so; if he is anxious to retreat, delay on purpose that he may carry out his intention." The object is to make him remiss and contemptuous before we deliver our attack.]