杯弓蛇影 — “Bow's reflection in a cup, snake's shadow”

One summer, County Magistrate Ying Chen invited his clerk, Du Xuan, for a drink. The banquet was held in the hall, with a red bow hanging on the north wall. Due to the refraction of light, the shadow of the bow was reflected in Du Xuan's wine cup. Du Xuan saw it and mistook it for a snake wriggling in his cup, immediately breaking out in a cold sweat. However, since the magistrate was his superior and had specifically invited him, he dared not refuse and forced himself to take a few sips. When the servant offered to pour more, he made an excuse, rose, and departed.

Back home, Du Xuan became increasingly convinced that he had drunk wine with a snake in it. He felt the snake wriggling inside him, experiencing severe and unbearable chest and abdominal pain, making eating and drinking very difficult. His family quickly called a doctor, but despite taking many medicines, his condition did not improve.

A few days later, Ying Chen had a matter to discuss and visited Du Xuan's home, asking him about his illness. Du Xuan then recounted the incident of the snake in his wine cup that day. Ying Chen comforted him briefly and returned home. Sitting in the hall, he repeatedly recalled and pondered, unable to understand how there could have been a snake in Du Xuan's cup. Suddenly, the red bow on the north wall caught his attention. He immediately sat in the same spot where Du Xuan had sat, took a cup of wine, and placed it in the original position. He discovered that there was indeed a shadow of the bow in the wine cup, which, upon closer inspection, closely resembled a wriggling snake.

Ying Chen immediately ordered a carriage to fetch Du Xuan. He had Du Xuan sit in the original spot and asked him to carefully observe the shadow in the wine cup, saying, “The snake you spoke of in the cup is merely the reflection of the bow on the wall; there is nothing else strange. Now you can rest assured!” After Du Xuan understood the truth, his doubts immediately vanished, and his illness quickly recovered.