This English version was translated from the Chinese original with AI assistance. The Chinese text is authoritative.
口
In brief: space-time, the Three Realms, the small universe of the body
Common reading
囗 is the ancient form of 围 (wéi, “surround”), originally meaning to encircle. The Shuowen: “囗 means to go around; it depicts a circuit.” Duan Yucai’s commentary: “Surround and around should be written with this character.” Guangya, “Shigu IV”: “围 means to wrap.” Book of Changes, “Xici I”: “It encompasses the transformations of heaven and earth.” The meaning of the frame 囗 shows in 國 (guó, “country”): from 囗 and 或; 域 was originally written 或 and means the same as 国, originally a state. The Son of Heaven received the mandate of heaven to rule and teach “all under heaven”; kings and lords enfeoffed by him guarded the people and taught all beings in their fiefs, which formed states, the large called 邦, the small 国. So this 口 has the senses of surrounding and encircling, and also of enclosing and protecting.
The 口 of a person usually means the mouth for speaking and eating; one more person means one more mouth to feed, so it mainly refers to an individual, a particular person. It also means speaking, and characters related to speech take the mouth radical.
Design reading
The two horizontals above and below symbolize heaven and earth, or space; the two verticals at the sides stand for past and future, symbolizing time; together they are space-time. Closing off above and below (heaven and earth) and left and right (past and future, or going in and out) forms an enclosed space, which in the terms of the cultivation world is “the Three Realms”. “No matter how high a god is, without the Creator’s consent it may not freely enter or leave the Three Realms.” Shizi, Book II: “The four directions with above and below are called 宇; past and present are called 宙.” Beings within the Three Realms cannot leave them, so the Three Realms are their greatest range of activity, that is, their universe, and so this 口 also stands for the universe.
Another layer: the left vertical also stands for the start of the rectification of the Fa; the horizontal turn stands for cultivating (丨) according to the Great Law (一); the bottom horizontal joining the two verticals stands for the Great Law entering the world and saving, with the Great Law, beings enclosed in the rolling red dust of material space-time. The material space-time we live in within the Three Realms is a strongly enclosed place, so the frame 囗 generally also stands for a material space with enclosed borders (as in 国, a country).
The 口 of a person has two layers of meaning. One is the mouth that speaks: what is said must accord with the principles of heaven and earth, be restrained, and the mouth must be cultivated. The other is the person: “the Daoists regard the human body as a small universe”, so the small frame 口 refers both to a person and to the small universe of the human body.
Related characters
About this entry
This entry is taken from the edited manuscript of LI Xutong’s Exploring the Design Mysteries of Chinese Characters. The common reading follows traditional philology, the Shuowen Jiezi and other classics, and modern dictionaries; the design reading recovers the rationale of the character’s formation from the meanings of its strokes, the pairing of yin and yang, and the nine-palace layout, following the New Six Scripts. The premise of the design reading, that the generative mechanism of Chinese characters was designed, is an axiom of this system and differs from the evolutionary account usual in philology; the two readings are kept apart, as surface and depth.