During the Three Kingdoms period, a man named Ren Kai in the state of Wei displayed extraordinary talent from a young age, earning the deep respect of Emperor Ming of Wei. The emperor married his daughter, Princess Qi, to Ren Kai and bestowed upon him numerous imperial gifts from the emperor, showing great favor.
In 265 AD, Sima Yan, grandson of Sima Yi, usurped the throne and established the Western Jin Dynasty, known historically as Emperor Wu of Jin. He appointed Ren Kai as an imperial advisor. During his tenure, Ren Kai's sharp intelligence and competence earned him the emperor's deep trust, and many important policies were consulted with him before implementation.
During the Jin Dynasty, one of its founding heroes, General-in-Chief Jia Chong, was constantly flattering the emperor, which angered minister Ren Kai and other officials. When a rebellion broke out at the border, Ren Kai seized the chance to petition the emperor: "Your Majesty, I recommend General Jia Chong to lead the campaign and guard the frontier." This was actually a scheme to banish Jia Chong from the capital, Luoyang. Jia Chong knew Ren Kai was behind it but dared not defy the imperial order.
On that day, Imperial Secretary Xun Xu hosted a farewell banquet for Jia Chong at the Sunset Pavilion, advising him to quickly betroth his daughter Nanfeng to Crown Prince Sima Zhong to secure his stay in Luoyang. Meanwhile, heavy snow fell around the capital, piling up two feet deep and halting the army's departure. Seizing the opportunity during an imperial banquet, Xun Xu petitioned the emperor to have the crown prince marry Jia's daughter, and the delighted emperor agreed. A few days later, Emperor Wu issued an edict ordering Jia Chong to remain in Luoyang with his original post.
Jia Chong, thanks to his daughter's marriage, managed to remain in Luoyang. Though he harbored deep resentment toward Ren Kai, he never showed it outwardly, always flattering Ren Kai to his face. Later, Jia Chong repeatedly praised Ren Kai before Emperor Wu, claiming he had an eye for talent and recommending him for the post of Minister of Personnel. The emperor, unaware of Jia Chong's true intentions, immediately agreed.
Although this promotion to Minister of Personnel was not a demotion, it stripped away much of his power, leaving him with little chance to discuss national affairs. So Jia Chong and Xun Xu began whispering slander to the emperor, claiming that Ren Kai lived a life of decadent luxury and had even secretly hoarded imperial gifts from the throne. Without sending anyone to investigate, the emperor readily believed their words and dismissed Ren Kai from his post.
In truth, those imperial gifts had originally been bestowed by Emperor Ming of Wei upon Princess Qi. Wrongfully accused and unable to defend himself before the throne, Ren Kai grew deeply indignant and abandoned all restraint. He spent his days indulging in wine and feasting, spending ten thousand coins on a single meal yet still finding it unsatisfying. This behavior handed Xun Xu and Jia Chong exactly the evidence they needed to frame him further. The emperor, seeing this, completely lost faith in Ren Kai, reducing him to a mere sinecure official and never entrusting him with real responsibility again.
When asked, "You see Ren Kai so falsely accused—will you just sit by and do nothing?" He Qiao, a friend and imperial advisor, replied, "Ren Kai's situation is like the Beixia Gate—on the verge of collapse, not something a single beam can prop up." This gave rise to the idiom "A Single Beam Cannot Support a Falling House," used to describe how one person's strength cannot reverse a crumbling situation.
Source: *A New Account of the Tales of the World*, Chapter "Unrestrained Conduct"
Meaning of the Idiom: Later, the Chinese idiom "一木难支" came to describe how one person's strength cannot reverse a crumbling situation.