Goa Tse (寡啧 gua3 ze2, Pinyin: Guá Zě, Wade Giles: Koa Tze) was a Taoist monk in the line of Chuang Tse (Tzu), active in the Chinese province of Yuguanzi around 455 BC. Famous for writing an early I Ching lecture book, Goa Tse was to become a key figure within Chinese philosophical thinking, and although many of the tales surrounding him are more mythological than historical, a number of facts about his life have survived.