Taijitu

In Chinese philosophy, a Taijitu (simplified Chinese: 太极图; traditional Chinese: 太極圖; pinyin: tàijítú; Wade–Giles: tʻai⁴chi²tʻu²) is a symbol or diagram (图; tú) representing Taiji (太极; tàijí; 'utmost extreme') in both its monist (wuji) and its dualist (yin and yang) in application as a deductive and inductive theoretical model. Such a diagram was first introduced by Neo-Confucian philosopher Zhou Dunyi (周敦頤; 1017–1073) of the Song Dynasty in his Taijitu shuo (太極圖說).

The Daozang, a Taoist canon compiled during the Ming era, has at least half a dozen variants of the taijitu. The two most similar are the Taiji Xiantiandao and the 無極圖; wújítú diagrams, both of which have been extensively studied during the Qing period for their possible connection with Zhou Dunyi's taijitu.Ming period author Lai Zhide (1525–1604) simplified the taijitu to a design of two interlocking spirals with two black-and-white dots superimposed on them, became synonymous with the Yellow River Map. This version was represented in Western literature and popular culture in the late 19th century as the "Great Monad", this depiction became known as the "yin-yang symbol" since the 1960s. The contemporary Chinese term for the modern symbol is referred to as 太极兩儀图 "the two-part Taiji diagram".

Ornamental patterns with visual similarity to the "yin yang symbol" are found in archaeological artefacts of European prehistory; such designs are sometimes descriptively dubbed "yin yang symbols" in archaeological literature by modern scholars.