Zhuangzi (sometimes also referred to as Zhuang Zhou, 369?-286 BC) dreamed that he had become a butterfly. The story appears in “On Seeing Things as Equal” in the classic Zhuangzi. Zhuangzi dreamed that he had become a butterfly, but woke up to find he was still himself. In fact he was not sure whether he had dreamed of becoming a butterfly or a butterfly had dreamed of becoming him. Zhuangzi used this dream to remind people that there must be a relative difference between oneself and others, between dreaming and wakefulness, and between all other things. However, these boundaries were not absolute and could be broken. Things were in constant transformation and circulation, which he called “the transformation of things (wuhua 物化).”

Once I, Zhuangzi, dreamed that I became a flying butterfly, happy with myself and doing as I pleased. I forgot that I was Zhuangzi. Suddenly I woke up and I was Zhuangzi again. I did not know whether Zhuangzi had been dreaming that he was a butterfly, or whether a butterfly had been dreaming that it was Zhuangzi. There must be a difference between the two, which is what I call “the transformation of things.” (Zhuangzi)