During the Wei and Jin dynasties, the uncle and nephew Ruan Ji and Ruan Xian were both renowned scholars of their time, known as "Greater and Lesser Ruan." Both were highly learned but unwilling to serve as officials. They often roamed the mountains, rivers, and bamboo groves with Ji Kang, Shan Tao, Xiang Xiu, Liu Jian, and Wang Rong, and were collectively called the "Seven Sages of the Bamboo Grove."
Uncle and nephew both loved music as much as they loved drinking. Ruan Ji could play the qin and sing, while Ruan Xian played the pipa excellently; he mastered musical theory and especially favored a plucked string instrument shaped like a moon guitar, which he was said to have invented, so later it was called "Ruan Xian," or simply "Ruan."
During the Wei-Jin period, the Ruan clan all lived on the same street—Ruan Ji and his nephew Ruan Xian lived on the south side, while their wealthier cousins occupied the north side. Despite their poverty, the uncle and nephew never felt inferior, holding their heads high with quiet dignity.
According to an old custom, on the seventh day of the seventh month each year, every household would bring out all their clothes to air them, preventing mold and moth damage. The wealthy Ruan brothers living north of the street wore fine silks and ate delicacies, so their displayed clothes dazzled the eye. Seeing the courtyard across the way filled with garments, Ruan Xian said to his uncle, "Let's bring out some of our clothes to air too!"
After searching high and low for something to air, he could only find a coarse cloth ox-nose pants, which he strung on a bamboo pole and hung high in the courtyard.
When a neighbor saw Ruan Xian's humble clothes hung out for the airing festival, he said, "You might as well skip this custom—airing such shabby garments is too embarrassing!" But Ruan Xian replied, "It's a tradition, so we can't very well ignore it! Let them hang as they are." Today, the idiom "unable to escape custom" describes following social conventions despite personal reluctance.
Source: *A New Account of the Tales of the World*, Chapter "Unrestrained Conduct"
Meaning of the Idiom: Later, the Chinese idiom "未能免俗" came to describe how following social conventions despite personal reluctance.