Zhūang Zi (py), Chuang Tzu (W-G), or Chuang Tse (Chinese: 莊子, literally meaning Master Zhuang) is a famous philosopher in ancient China, lived around the 4th century BC (Hundred Schools of Thought, Warring States Period). He was from the Town of Meng (蒙城 meng2 cheng2) in the State of Song (宋國 song4 guo2) (now Shangqiu (商邱 shang1 qiu1), Henan). His given name was Zhou (周 zhou1). He is also known as Meng Official (蒙吏 meng2 li4), Meng Zhuang (蒙莊 meng2 zhuang1) and Meng Elder (蒙叟 meng2 sou3).
The Taoist book Zhuang Zi (《莊子》) of the same name believed to be written by Zhuangzi and others. One phrase from the book that has been popuarlized is the idiom "Zhuang Zhou dreamed he was a butterfly" (莊周夢蝶 zhuang1 zhou1 meng4 die2) from the chapter "On Arranging Things" (齊物論 qi2 wu4 lun4, the second part of the book). The idiom originates from the event that one night, Zhuangzi dreamed that he was a carefree butterfly flying happily. And after he woke up, he thought that maybe he was actually a butterfly dreaming that he was a person. It hints at many questions in the philosophy of mind and epistemology, such as Descartes' famous question of how one knows one exists.
In general, Zhuangzi's philosophy is rather antinomian, repeatedly arguing that our experience is limited and that using our limited tools (language, cognition, etc.) to judge all things (wanwu) is foolish. Zhuangzi's thought can also be considered a precursor of multiculturalism and subjectivism, with its recognition of many value systems. For example, in the fourth section of "The Great Happiness" (至樂 zhi4le4, the 18th section of the book), Zhuangzi talks to a skull he sees lying at the side of the road. Zhuangzi expresses sorrow that the skull's former owner is now dead, but the skull retorts, "How do you know it's bad to be dead?" In another example, again from "On Arranging Things," one person points out to another that animals have different values. He mentions two famous women who are considered beautiful by people, but if a fish saw them, it would swim away into the depths; if a bird saw them, it would fly away into the sky, and if a deer saw them, it would gallop away at full speed. "Which of these knows what is truly beautiful?" However, this subjectivism is balanced with a kind of sensitive holism in the conclusion of this well-known debate about what fish enjoy: