structural:reformatting, linguistic:translation, structural:expansion, linguistic:voice_change
Yin and yang — gui and shen

Yin Chinese: 陰 and yang Chinese: 陽, whose root meanings respectively are "shady" and "sunny", or "dark" and "light", are modes of manifestation of the qi, not material things in themselves. Yin is the qi in its dense, dark, sinking, wet, condensing mode; yang denotes the light, and the bright, rising, dry, expanding modality. Described as Taiji (the "Great Pole"), they represent the polarity and complementarity that enlivens the cosmos. They can also be conceived as "disorder" and "order", "activity" or "passivity", with act (yang) usually preferred over receptiveness (yin).

The concept Chinese: 神 " shén " (cognate of Chinese: 申 shēn, "extending, expanding") is translated as "gods" or "spirits". There are shén of nature; gods who were once people, such as the warrior Guan Gong; household gods, such as the Stove God; as well as ancestral gods (zu or zuxian). In the domain of humanity the shen is the "psyche", or the power or agency within humans. They are intimately involved in the life of this world. As spirits of stars, mountains and streams, shen exert a direct influence on things, making phenomena appear and things grow or extend themselves. An early Chinese dictionary, the Shuowen jiezi by Xu Shen, explains that they "are the spirits of Heaven" and they "draw out the ten thousand things". As forces of growth the gods are regarded as yang, opposed to a yin class of entities called Chinese: 鬼 " guǐ " (cognate of Chinese: 歸 guī, "return, contraction"), chaotic beings. A disciple of Zhu Xi noted that "between Heaven and Earth there is no thing that does not consist of yin and yang, and there is no place where yin and yang are not found. Therefore, there is no place where gods and spirits do not exist". The dragon is a symbol of yang, the principle of generation.

In Taoist and Confucian thought, the supreme God and its order and the multiplicity of shen are identified as one and the same. In the Yizhuan, a commentary to the Yijing, it is written that "one yin and one yang are called the Tao... the unfathomable change of yin and yang is called shen ". In other texts, with a tradition going back to the Han period, the gods and spirits are explained to be names of yin and yang, forces of contraction and forces of growth.

While in popular thought they have conscience and personality, Neo-Confucian scholars tended to rationalise them. Zhu Xi wrote that they act according to the li. Zhang Zai wrote that they are "the inherent potential (liang neng) of the two ways of qi ". Cheng Yi said that they are "traces of the creative process". Chen Chun wrote that shen and gui are expansions and contractions, going and coming, of yin and yang — qi.