Ji An, a renowned official of the early Western Han Dynasty, was studious, straightforward, and chivalrous, always eager to help others in distress. However, he was also arrogant and loved to point out people's faults to their faces, making even the court ministers fear him. Before the emperor, he spoke without any tact, bluntly and repeatedly clashing with the sovereign. For instance, when the emperor ambitiously sought to conquer the Xiongnu with military force and subdue all surrounding regions, Ji An advised, "Your Majesty must not raise an army, lest you exhaust the people and drain the treasury." The emperor, both furious and helpless, could only sigh, leaving Ji An's official rank stagnant for many years without promotion.
Gongsun Hong and Zhang Tang were originally mere "pen-pushing clerks," but when the emperor began revering Confucianism and revising the legal code, they seized the chance to wag their tongues and craft harsh, meticulous laws that ensnared countless people in guilt—using this to curry favor and rise swiftly through the court. Gongsun Hong, in particular, soared so high that he eventually became the prime minister.
When Ji An was among the Nine Ministers, Gongsun Hong and others were mere clerks. Later, Gongsun Hong rose to prominence and equaled Ji An's rank. After Ji An exposed Gongsun Hong's deceitful flattery and schemes against court officials, Gongsun Hong soon became Chancellor. Displeased, Ji An once told the emperor, "Your Majesty uses court officials like stacking firewood—the later ones end up on top!" meaning that junior officials now outranked their seniors.
Later, the idiom "The Latecomers Surpass the Former" is often used to describe those who come after surpassing those before.
Source: *Records of the Grand Historian*, "Biography of Ji An"
Meaning of the Idiom: Later, the Chinese idiom "后来居上" came to describe those who come after surpassing those before.