During the late Eastern Han Dynasty, the warlord Gongsun Zan had originally fortified his stronghold in Jizhou.
A recent children's rhyme circulates in Jizhou: "South of Yan, north of Zhao, a stone in the center where one may hide from the world."
The Wuhuan and Xianbei tribes from the north, along with Yuan Shu and Yuan Shao from the south, were constantly raiding Jizhou, leaving Gongsun Zan restless with worry. He summoned a diviner and asked, "What does this children's rhyme mean?"
The magician said, "In ancient times, the southern border of Yan and the northern border of Zhao sometimes belonged to Yan and sometimes to Zhao. That land was Yizhou, built on a hillside with a mountain at its back. In war, attackers could only charge uphill, making it an ideal place to defend."
After hearing this, Gongsun Zan resolved to move the capital.
Gongsun Zan dug ten moats outside Yizhou, each lined with a wall, and built a central castle over ten zhang high storing three million hu of grain, calling it Yijing, where he stationed himself.
Gongsun Zan, residing in Yijing, said with great satisfaction, "The Art of War says attacking a city with a hundred watchtowers is asking for trouble. Now Yijing has a thousand watchtowers—who can do anything to me?"
In truth, Gongsun Zan had fallen into Yuan Shao's trap—Yuan Shao had spread a children's rhyme to trick Gongsun Zan into holing up in an isolated city, sapping his will to fight and eliminating a rival for the empire.
When Yuan Shao's massive army laid siege to Yijing, Gongsun Zan held his ground behind the city's defenses. Though the walls kept the enemy at bay for now, morale among his troops was crumbling as food supplies dwindled day by day. To make matters worse, Yuan Shao's soldiers were tunneling underground day and night, planning to launch a surprise attack from both above and below.
Gongsun Zan could no longer hold back
His subordinates advised him, "The entire army has lost its will to fight. The only reason we can still hold out is that everyone's families and possessions are within the city. Yijing is our last stronghold. If we abandon the city and lead the troops out to attack, it would be like releasing birds and beasts from their cages—the consequences would be dire. We believe the best strategy is to patiently await reinforcements from the prince and launch a coordinated attack from within and without."
Gongsun Zan wrote a letter and had it swiftly delivered to his son. The letter read: "Yuan Shao's army moves like gods and ghosts—drums and horns echo from beneath the earth, while cloud ladders and battering rams rain down upon our walls. Trapped in this lonely city, I am at my wit's end. Ride swiftly with light cavalry to rescue me. When you arrive, light a beacon fire on the northern hill. Upon seeing it, I will open the gates and strike the enemy by surprise, crushing Yuan's forces."
The letter was intercepted by Yuan Shao. As planned, Yuan's forces lit signal fires at Beixia Gate, luring Gongsun Zan's soldiers out in full force into an ambush. When the routed troops retreated back to the city, they discovered Yuan's men had already tunneled through the walls and captured Yijing.
Gongsun Zan, exhausted and out of options, shut himself in and took his own life.
"Wú suǒ liáo lài" later evolved through usage into "bǎi wú liáo lài," used to describe having nothing to rely on, feeling lonely and bored.
Source: *Records of the Three Kingdoms*, "Biography of Gongsun Zan"
Meaning of the Idiom: Later, the Chinese idiom "百无聊赖" came to describe having nothing to rely on, feeling lonely and bored.