During the Warring States period, the state of Zhao had a man named Zhao Sheng, a talented and meritorious noble whose fief was in Pingyuan County, earning him the title Lord Pingyuan.
In 262 BCE, King Ying Zheng of Qin sent his great general Bai Qi to attack the state of Han. A master of warfare, Bai Qi swiftly captured Yewang (in present-day Qinyang County, Henan) and set his sights on the Shangdang Commandery (modern-day Changzhi, Shanxi).
Feng Ting, the governor of Shangdang, found himself with too few troops to hold off the Qin army. He told his officers, "Shangdang is about to fall. Surrendering to Qin is worse than surrendering to our neighbor, Zhao. If the King of Zhao accepts our submission, the King of Qin will surely blame him and attack Zhao. That way, Han and Zhao will unite against mighty Qin."
His officers all voiced their approval, so Feng Ting dispatched an envoy bearing a letter and the map of Shangdang to King Xiaocheng of Zhao. Delighted, the king summoned his advisors, Lord Pingyang Zhao Bao and Lord Pingyuan Zhao Sheng, to discuss the matter.
Zhao Bao said, "Shangdang Commandery is now the target of the Qin army. Feng Ting knows he cannot hold Shangdang, yet instead of surrendering to Qin, he wants to submit to our state. I believe he harbors ill intentions. Feng Ting's aim is to shift the blame onto us, making the Qin army turn and attack our state. Therefore, I advise Your Majesty not to accept this offer."
But Lord Pingyuan Zhao Sheng, blinded by greed, said, "Your Majesty, Shangdang Commandery has 17 cities. We can gain this vast territory without spending a single soldier—a rare opportunity indeed. I hope Your Majesty will not let it slip."
Lord Pingyuan's proposal pleased King Xiaocheng of Zhao, who promptly dispatched him to Shangdang to meet Feng Ting, formally accepting the seventeen cities of the Shangdang Commandery and granting Feng Ting the title of Lord Huayang.
When King of Qin learned of this, he was furious and ordered Bai Qi to lead an army against Zhao's Changping (northwest of modern Gaoping, Shanxi). In the end, Zhao's 400,000 troops were trapped at Changping and annihilated by Qin forces.
Sima Qian, author of the *Records of the Grand Historian*, commented on Zhao Sheng in the chapter "Biographies of Lord Pingyuan and Yu Qing," noting that while Lord Pingyuan was a man of great talent, in this matter he failed to consider the broader picture—blinded by personal gain, he lost all reason and could not distinguish right from wrong, leading Zhao to its devastating defeat at Changping, with the capital Handan nearly falling.
Later, the idiom "blinded by greed" came to describe someone whose mind is clouded by selfish interests, causing them to forget everything else.
Source: *Records of the Grand Historian*, "Biographies of Lord Pingyuan and Yu Qing"
Meaning of the Idiom: Later, the Chinese idiom "利令智昏" came to describe how someone whose mind is clouded by selfish interests, causing them to forget everything else.