成语寓言：对牛弹琴 Idiom and Fable: Play music to a cow

这个成语故事源于汉朝（公元前202年～公元220年），讲述了战国时期的一个音乐家为牛演奏音乐的故事，意思是对不讲道理的人讲道理，完全没有用处。

This idiom story originated from the Han Dynasty (202 BC to 220 AD), and tells the story of a musician in the Warring States period playing music for cows. This story means that it is completely useless to reason with unreasonable people.