During the Spring and Autumn Period, a man living in the State of Song had three sons. They all became high-ranking officials, particularly the second son who was deeply trusted by the emperor. The third son had to flee to a foreign country due to treason. Although they were siblings, the eldest son killed the second when he discovered that it was he who set up their little brother and called up a great many soldiers to rebel the State of Song.
Then, the third son who went into exile heard what had happened and returned to hold the eldest with reinforcements from the State of Wu. The State of Song was in imminent danger with the troops of Wu on the way to the State of Song. A senior official in the State of Song said, "We first must make them know our strength so we can destroy the enemy's morale. Then when we begin to attack the enemies we will definitely win. Now the Wu army is fatigued and has no time to rest. We should then attack by surprise. Otherwise it will be hard to defeat them when they become strong". The emperor of the State of Song adopted his opinion and they soon won the war.