Chuang Chou returned home and for three months looked unhappy." Lin Chu in the course of tending to his master's needs, questioned him, saying, "Master, why is it that you are so unhappy these days?"Go here to read the introductory post to the chapters of the Book of Chuang Tzu.
Chuang Chou said, "In clinging to outward form I have forgotten my own body. Staring at muddy water, I have been misled into taking it for a clear pool. Moreover, I have heard my Master say, `When you go among the vulgar, follow their rules!' I went wandering at Tiao-ling and forgot my body. A peculiar magpie brushed against my forehead, wandered off to the chestnut grove, and there forgot its true self. And the keeper of the chestnut grove, to my great shame, took me for a trespasser! That is why I am unhappy."
~ Burton Watson translation via Terebess Asia Online ~