庄子·蝶梦 A Dream of the Butterflies

Once upon a time, I, Chuang Chou, dreamt that I was a butterfly, fluttering hither and thither, to all intents and purposes a butterfly. I was conscious only of my happiness as a butterfly, unaware that I was Chou. Soon I awaked, and there I was, veritably myself again. Now I do not know whether I was then a man dreaming that I was a butterfly, or whether I am now a butterfly, dreaming that I am a man. Between a man and a butterfly, there is necessarily a distinction. The transition is called “the transformation of material things.”

昔者庄周梦为胡蝶，栩栩然胡蝶也。自喻适志与，不知周也。俄然觉，则蘧蓬然周也。不知周之梦为胡蝶与？胡蝶之梦为周与？周与胡蝶，则必有分矣。此之谓物化。