Hidden Stems: The Inner Rooms of the Earthly Branches
In a Nutshell
Every Earthly Branch "hides" one to three Heavenly Stems inside it — the Hidden Stems. Never judge a branch by its surface element alone; there are residents in the inner rooms.
Quick facts
| Item | Detail |
|---|---|
| What they are | 1–3 Heavenly Stems hidden inside each Earthly Branch |
| Pure-qi branches | Zi, Wu, Mao, You — each hides exactly one stem |
| Principal qi | The branch's "master" stem — strongest |
| Residual qi | Leftover energy from the previous season — weakest |
| Used for | Measuring elemental strength, Ten God placement, Chart Pattern |
The Hidden Stem table (standard Zi Ping convention)
| Branch | Hidden Stems |
|---|---|
| Zi | Gui |
| Chou | Ji, Xin, Gui |
| Yin | Jia, Bing, Wu |
| Mao | Yi |
| Chen | Wu, Yi, Gui |
| Si | Bing, Geng, Wu |
| Wu | Ding, Ji |
| Wei | Ji, Ding, Yi |
| Shen | Geng, Ren, Wu |
| You | Xin |
| Xu | Wu, Xin, Ding |
| Hai | Ren, Jia |
Easy pattern: Zi, Wu, Mao, and You hold a single "pure" qi; the rest hide two or three.
Principal qi and residual qi
Take Yin: it hides Jia, Bing, Wu. Jia Wood is Yin's "principal qi" (the master of the house); Bing Fire is its "Birth-stage qi" (Yin is Fire's Birth position in the Twelve Stages); Wu Earth is "residual qi" (the tail of the previous season). In strength: principal strongest, residual weakest.
Similarly: Shen hides Geng, Ren, Wu (Geng Metal principal, Ren Water Birth-stage, Wu Earth residual); Si hides Bing, Geng, Wu (Bing Fire principal, Geng Metal Birth-stage, Wu Earth residual); Hai hides Ren, Jia (Ren Water principal, Jia Wood Birth-stage).
Why Hidden Stems matter
- Measuring elemental strength: counting only the visible stems misses the energy inside the branches — strength readings go wrong.
- Reading Ten God placement: to see whether your Wealth star "has roots," check whether the stem's Wealth finds a same-element ally among the branch Hidden Stems — rooted wealth and rootless wealth carry very different weight.
- Fixing the chart's structure: Chart Pattern reads which Ten God the Month branch reveals — "reveals" means a Hidden Stem showing through to the surface.
A note on conventions
Classics differ slightly on some Hidden Stems (e.g., which residual qi belongs where); this wiki follows the standard Zi Ping convention. MoZhu's engine computes per its implementation and stays consistent in interpretation.
MoZhu tip
The brute-force way to learn Hidden Stems: take your own chart, expand every branch's Hidden Stems in writing, and count how many "allies" (your own element) are hiding in the eight characters. After one round of counting, strength starts to make sense.
Classical sources
Hidden Stem (cang gan) tables are documented across classical BaZi literature in the standard Zi Ping convention.
*For entertainment purposes only.*