杯弓蛇影

晉朝人樂廣曾經請朋友到家裡喝酒。當那個朋友喝了一口酒，正準備把杯子放到桌上的時候，突然看見杯子裡漂著一條小蛇，心裡就有點不安，不過還是勉強喝了那杯酒。

回家之後，那個朋友就生了病。樂廣派人去問候他，才知道原因是他懷疑杯子裡有小蛇。所以，樂廣很仔細地觀察他家一遍，追究事情的緣由。後來，他發現牆上掛了一把弓，弓的影子倒映在酒杯裡看起來很像一條小蛇。

後來，他再把朋友請到家裡，讓他朋友看清楚牆上的弓，再請他看看杯子裡的東西。最後，他朋友終於明白杯子裡並沒有小蛇的時候，病立刻就好了。

To Mistake The Reflection of The Bow For a Snake

During the Chin dynasty, there lived a man named Yue Guang. One day, he realized that there was one of his friends whom he hadn't seen in awhile, and sent someone to call on him. The friend said to his visitor, "A few days ago, I was drinking wine at Yue Guang's house, when suddenly I noticed a snake in my glass! I felt very uncomfortable, and barely finished the wine. Ever since I got home that day I've been sick, and I just know it's that snake acting up in my stomach!" When word of this got back to Yue Guang, he immediately thought of the bow that was hanging on his wall. If this bow were reflected in a glass of wine, when the wine moved, wouldn't the reflection resemble a small snake? Yue Guang quickly invited his friend over and explained this theory to him. When the friend heard this, he was very relieved, and suddenly his illness disappeard.

Now, when a person needlessly worries about some small or imaginary thing, we can say that person is "mistaking the reflection of the bow for a snake."