How Do the Fifty Circulations Pass Through the Twenty-Seven Hou? From Single Pulse Point to Time Series

If the Twenty-Seven Hou were merely twenty-seven fixed positions, why would “Twenty-Seven Hou (II)” list a long sequence called “the tones of qi movement through the Fifty Circulations”?

Using “Qian-Gui-Zhou-Hou-Huangzhong” as an example, the text lists Zhi-An, Zhong-Jie, Shang-Gong, Yu-Sui, and so on through Zhong-Zhi, making fifty tonal-degree combinations.

It then says:

One channel has nine Hou: Huangzhong has nine Hou—Zhou, Ge, Qin, Xian, Mi, Kun, Sui, Duan, Hui… The other channels follow the same method.

And finally summarizes:

She is the position reached by the meeting of Nourishing and Defensive qi; Hou is where pulse, breath, tone, and lü enter and leave.

The same position therefore changes over time

“Zhou-Hou-Huangzhong” does not have only one fixed tone. As the Fifty Circulations proceed, the tonal-degree combination that appears there changes.

The Hou position is therefore comparable to a fixed sensing location, while the moving qi is the signal continually passing through it.

Seen this way, the temporal character of Hou becomes clear: the position stays fixed while the state moves.

Pulse diagnosis is therefore not merely palpating one instant

If diagnosis only said “this point is strong, that point is weak” at one moment, the concept of the Fifty Circulations would be difficult to use. The Mirror Classic is more interested in where pulse movement begins within a breath, where it ends, and how it shifts across different phases.

Later “Qiheng” passages explicitly describe routes such as “in one exhalation pulse movement begins at Jiang and rises until Yi” or “in one exhalation pulse movement begins at Cheng, and the next movement reaches Shi.”

This is already very close to a time-series descriptive grammar: event onset, traversed positions, amplitude, and endpoint all have to be recorded.

This also clarifies the difference between “flow” and “pour”

Earlier passages distinguished flow as communicative passage and pouring as qi interaction. In the Twenty-Seven Hou, qi does not stay at one Hou; it flows in, pours in, and turns out again.

What is truly being diagnosed is therefore not a static map, but how qi moves across the map.

By this point, the first five series have built enough observational tools. The next series, “Qiheng,” begins to answer the central diagnostic question: given these measurements, what counts as abnormal?