During the Warring States period, various vassal states often waged wars to seize territory. The State of Qin sent its general Bai Qi to attack the State of Han, capturing a piece of land called Yanwang.

Nearby, in another territory called Shangdang, local officials, seeing how easily Yanwang was taken by the Qin army, feared that Shangdang would also be undefendable. They wrote to the State of Zhao, expressing their willingness to surrender and hoping for Zhao's protection.

The Zhao monarch and his officials were divided on whether to accept Shangdang's surrender, leading to a fierce debate. Prince Pingyuan (Zhao Sheng) argued, "Shangdang is such a large territory; we can acquire it without deploying a single soldier. Why shouldn't we?" Prince Pingyang opposed this, saying, "It is precisely because we gain such a benefit effortlessly and accept it so easily that it may invite great disaster."

King Zhao, unwilling to let go of this seemingly easy gain, supported Prince Pingyuan's proposal and sent him to receive Shangdang, annexing it into Zhao's territory. Upon learning this, Qin believed Zhao was deliberately opposing them and ordered Bai Qi to lead a large army to attack Zhao.

As a result, Zhao's army of 400,000 soldiers was completely annihilated, and its capital Handan was besieged. Later, Prince Pingyuan took Mao Sui to the State of Chu, persuading the King of Chu to form an alliance with Zhao against Qin. Chu eventually sent troops, which lifted the siege of Handan.

The King of Zhao and Prince Pingyuan, blinded by the immediate benefit of acquiring Shangdang's land, nearly led the State of Zhao to ruin. Later generations described their actions as "利令智昏" (lì lìng zhì hūn), meaning to be blinded by greed.