As an icon the Tai Chi is a symbol, composed of the Yin and Yang circle, surrounded by eight trigrams. It, in terms of function is the underlying philosophy of all Chinese, and "classical" Oriental philosophy. According to the scholar Fung Yu-Lan, "The History of Chinese Philosophy, Vol 2". Princeton, 1953, the philosophies of Pythagoras, and the Tai Chi are almost identical. The concept of Chi, and Sophia (wisdom), Logos, and Tao, meaning "Word", are identical. The power of male and female polarities in the Tai Chi, resemble the ideas of Pronoia, and Protophanes, in the concept of "Barbelo". (See Barbelo, and Sethian Monadology. See also; "A Valentinian Exposition".) The Tai Chi is associated with the "Book of Changes", (I Ching), in Chinese Philosophy. Pythagoras is thought to have studied Chinese Philosophy, and obviously did. (See Bulfinch"s Mythology, Gramercy, Crown Pub. 1979.) The analogy to the Tai Chi, Sethian values are in "Tetrakys of the Decad"s", monadic values.