Cun, Guan, and Chi Are Not Just Three Boxes: What Are the Twenty-Seven Hou?

Conventional discussion of the Cun-mouth pulse easily creates the impression of “three boxes: Cun, Guan, and Chi.” Once the Mirror Classic of Bian Que enters the chapter on the “Twenty-Seven Hou,” its observational resolution increases sharply.

The text says:

Hou are the offices of Qiheng yin and yang and the instruments by which pulse and breath are measured. The qi of the Twelve Channels all greatly converges in the Twenty-Seven Hou.

It then divides the Twenty-Seven Hou into three groups:

Zhou, Cha, Jin, Duan, Yi, Yue, Kun, Lian, and Zhi are the Hou of the Cun measure; Xian, Shou, Zeng, Ge, Yi, Shi, Hui, Li, and Zheng are the Hou of the Guan measure; Sui, Da, Le, Mi, Ju, Sheng, Qin, Cheng, and Jiang are the Hou of the Chi measure.

Cun, Guan, and Chi therefore each contain nine Hou.

Hou are not another twenty-seven channels

A Hou is first an observation position / observation state. The text calls it an “instrument for measuring pulse and breath,” used to observe changes and depth in the movement of qi.

The Twenty-Seven Hou therefore do not add twenty-seven new lines to the body. They subdivide the otherwise coarse three pulse regions so that the coming and going, high and low, and turning points of one pulse movement can be named with greater precision.

Why is such high resolution necessary?

Because earlier chapters have already introduced many variables: tone has high and low, lü has long and short, She has different positions, and the Nine Qi undergo shifts. If diagnosis ultimately reduced all of this to “Cun-Guan-Chi strong or weak,” much of the model could never become observable.

The Twenty-Seven Hou project these dynamics onto the accessible Qi-Mouth region, forming a finer spatial coordinate system.

“Hou” also carries a temporal meaning

Hou does not only mean where something is. It also indicates a point at which qi can be observed as it arrives. Later passages therefore speak of “the Nine Hou of a given lü” and “the tones of the Fifty Circulations.”

The Twenty-Seven Hou thus have a dual character: they are spatial subdivisions, but also observation windows within the process of qi movement.

The next article examines what these twenty-seven unfamiliar names are actually marking on the pulse-diagnostic map.