In Neo-Confucian cosmology, it came to mean the "primordial universe" prior to the "Supreme Ultimate" state of being.

Common English translations of the cosmological wuji are "ultimateless"[1] or "limitless",[2] but other versions are "the ultimate of Nothingness",[3] "that which has no Pole",[4] or "Non-Polar".

Zhang and Ryden summarize the philosophical transformation of wuji: The expression 'limitless' and its relatives are found in the Laozi and the Zhuangzi and also in writings of the logicians.

[6] The term wuji first appears in the Tao Te Ching (c. 4th century BCE) in the context of returning to one's original nature: — (Mair 1990, chapter 28, p. 93)This is an instance of how wuji with "integrity" (Chinese: 德) can become dualistic by dividing into yin and yang.

The ten thousand things (the universe) then comes into existence:[7] 道生一，一生二，二生三，三生万物。The Taoist Zhuangzi (c. 3rd–2nd centuries BCE) uses wuji four times.

One syntactically playful passage says a sage can qiong wuqiong (窮無窮 "exhaust the inexhaustible"; also used in Xunzi above) and ji wuji (極無極 "[go to the] extreme [of] the extremeless").

94-5)The (11th century CE) Taijitu shuo (太極圖說, "Explanation of the Diagram of the Supreme Ultimate"), written by Zhou Dunyi, was the cornerstone of Neo-Confucianist cosmology.

However, Zhou thought of wuji and taiji as ultimately the same principle and concept that created movement,[10] life, and "the ten thousand transformations" (things).

The alternation and combination of yang and yin generate water, fire, wood, metal, and earth.

This Three is, in Taoist terms, the One (Yang) plus the Two (Yin), or the Three that gives life to all beings (Daode jing 42), the One that virtually contains the multiplicity.

Thus, the wuji is a limitless void, whereas the taiji is a limit in the sense that it is the beginning and the end of the world, a turning point.