During the Warring States Period, there was a musician named Gong Ming Yi, who played musical instruments very well. There were a great number of people fond of listening to him play, and who respected him greatly.

One day, Gong Ming Yi saw a cow when he was relaxing in the countryside. He thought, "Everybody compliments my music. Why don't I play some music for this cow?"

He played a piece of elegant quaint music for the cow, but the cow just kept grazing the grass with its head down. He played another piece of joyful music, but the cow still kept its head down to graze the grass and totally ignored him.

Gong Ming Yi showed off all his skills, but the cow still ignored him. Gong Ming Yi was disappointed and started to question his ability. A passerby said to him,"It's not because your ability is bad. It is because the cow can not understand music at all."

The cow could not understand the beautiful music like humans. The swanky musician tried his best to play for the cow, but it was just like trying to tell something to somebody who can hardly understand. The idiom "对牛弹琴" (Playing music for a cow) is used to describe this sort of situation, or kind of person.