Sometimes we say things we don’t mean. I’m not referring to words spoken in anger, but rather colloquialisms. Certain phrases that would mean one thing to a non-native speaker mean something completely different to someone who knows the story behind them. This is why, when I took Chinese a couple of years ago, our teacher would occasionally hand us all a story to learn about the meaning behind a Chinese phrase.
One day we read about a learned scholar and musician traveling alone along a country road. He was a rather conceited man, and jumped at every chance to display his superiority to others, whether it was by besting them in debate or by demonstrating his considerable musical skills. It had been some time since he had met anyone on his journey, and when you’re the sort of person who is better than everyone else, it’s hard to go a long time without showing off. There happened to be some cows in a nearby field, and since the scholar tended to consider other people on the same level as the beasts he was passing, he decided they would do. He’d show them. There was no way those cows could fail to be impressed by his skills. He unstrapped the zither he was carrying on his back, sat down in front of the lovely stringed instrument, and began to play beautifully. The cows, to his annoyance, continued chewing their cud and grazing on the occasional bit of grass. The scholar continued playing, getting more and more annoyed that his exquisite work was going unappreciated. What the scholar did not understand is that he was wasting his time; cows don’t understand music.
The Chinese phrase, 对牛弹琴 or “playing zither to a cow” is the equivalent of the English phrase “howling at the moon” or “don’t cast your pearls before swine.” Basically, you shouldn't put a huge effort into doing something that you know means nothing, since you’re just wasting your time and ability.
But perhaps what the scholar should have tried was some jazz. Cows apparently like that quite a bit.
Obligatory “When the saints come marching in” joke goes here