The Classic Self-Fulfilling Prophecy:
Pang Chuan Draws Fire
When the kingdoms of Wei and Chao made a joint attack on the Kingdom of Han, Han turned to the Kingdom of Ch'i for help. Ch'i obliged, sending General Tien Chi, with his advisor, Sun Pin, on a march straight toward Ta-liang, the capital of Wei.
With its capital threatened, the Wei army promptly abandoned its invasion of Han and rapidly countermarched to protect the capital.
Though he was responding to a bold stroke by the Ch'i army, the Wei commander and his men nevertheless held the Ch'i troops in contempt.
So Sun Pin decided to use Wei's low opinion of Ch'i to defeat the Wei army.
He ordered the Ch'i army to light 100,000 campfires the first night it entered the Kingdom of Wei, 50,000 on the second night as it moved further into the country, and 30,000 on the third night, after advancing even deeper into Wei territory.
General Pang Chuan, the Wei commander, was now in close pursuit. He watched each night as the number of fires in the Ch'i camp dwindled, and his low opinion of the Ch'i army was reinforced. Pang Chuan reasoned that the threat of an encounter with the seasoned troops of Wei had frightened the Ch'i troops, so they were deserting in large numbers. "I knew the men of Ch'i were cowards," he said.
Thus emboldened, Pang Chuan left his infantry behind and with just his light cavalry, pressed recklessly in pursuit.
But Sun Pin knew Pang Chuan was coming, and calculated he would reach Maling about dusk, where the path was narrow and ideal for an ambush.
There he stripped the bark of a tree and wrote on the trunk, "Under the tree shall Pang Chuan die!" and stationed 10,000 crossbowmen on either side of the path, with orders to shoot when they saw a flame on the path.
As Pang Chuan approached, he saw the bark peeled away and writing on the tree trunk. Unable to make out the words in the darkness, he called for a light.
Seeing the flame, the crossbowmen began shooting, killing Pang Chuan and routing the Wei army.
TCL, pgs. 13-15
Taken from http://www.sacklunch.net/SunTzu/suntzu_ch5.php
See also: SelfUnfulfillingProphecy, SelfNegatingProphecy