During the Spring and Autumn Period (770 BC-476 BC), war broke out frequently. The powerful State of Qi dispatched troops to attack the State of Lu. The King of Lu was horrified when he heard the news, since Qi was larger and more powerful than Lu, and Lu had little chance of success.
The crucial battle broke out in Changshao. The Qi troop beat their drums to signal the first attack. The Lu ruler was about to follow suit but was stopped by his general Cao Gui. He said, “Your Majesty, now it is not opportune for us to fight back. Would you mind waiting for a moment?” When the Qi troops drew near, Cao Gui suggested that his king order his men to hold their positions instead of fighting back. Meanwhile, archers were ordered to fire at will. The arrows slowed the advance of the Qi troops. The enemy had no choice eventually but to retreat.
Later, the Qi troops beat their battle drums for a second time. Cao Gui once again held back the counterattack, using only his archers to slow the enemies’ attack.
When they beat their war drums a third time, the Qi troops lost all morale. At this time, Cao Gui said, “Your Majesty, now, we can hit back!”
With their drums beating out a defiant rhythm, the Lu troops rushed out and successfully defeated the Qi troops. Despite their numerical superiority, the Qi troops were powerless against the onrushing enemy. In no time, the Qi were defeated. The King of the State of Lu was very excited and wanted to order his men to give chase to the enemy. But he was dissuaded. Jumping down from his war wagon, Cao Gui carefully checked the ruts left by the Qi troops. Then, he climbed to higher ground to observe the fleeing Qi troops. Next, he said, “Your Majesty, now, it is time to give chase!”
The King of the State of Lu accepted Cao Gui’s advice and finally succeeded in expelling the enemy from his state.
When the war was over, the King of the State of Lu asked Cao Gui why they waited to launch their attack until the Qi troops’ third wave of attack. Cao Gui said, “Fighting largely relies on soldiers’ courage. After the first attack, the enemy soldiers’ morale was at its peak. After the second attack, their morale became a little weaker. And after the third attack, their morale was completely gone. When our army sounded our drums, our buoyant troops had no trouble defeating a dispirited and tired enemy.”
“Then, why didn’t you want me to give chase?”
Cao Gui smiled and said, “The State of Qi is so powerful and it has more soldiers and tacticians than we do. I was afraid that they were just pretending to be defeated and were actually laying a trap for us. Therefore, I checked the ruts left by their chariots, and saw their disordered banners. Judging from these, I was sure that they were really defeated. Then I was sure it was Ok to give chase.”