Source: Han dynasty author Mou Jung's Li Huo Lun (Explaining Matters).
Meaning: It can be used to insult a listener (or viewer) who is unable or unwilling to appreciate what one is trying to communicate. In this sense it approximates the English expression "casting pearls before swine." However, it also describes the foolishness of some one who doesn't understand to whom they should direct their communication (like trying to get a water buffalo to appreciate a zither). Thus it may serve to insult either or both of the two parties.
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1. Kung-ming Yi was a renowned zither player.
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2. Once out of boredom he played a tune for a water buffalo.
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3. The water buffalo, unmoved; simply kept munching on the grass.
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4. kung-ming thus discovered how pointless it is to play fine music for someone who cannot understand it.
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5. Sighing, he casually stroked the zither, producing a sound like that of a mosquito approaching. That finally produced a reaction from the water buffalo!