What Is the Stem-Branch Relationship System?
The Stem-Branch relationship system is a set of rules in Bazi (Four Pillars) analysis that describes the various interactive effects between Heavenly Stems, between Earthly Branches, and between Stems and Branches. These relationships serve as the core mechanism through which Luck Cycles and Annual Luck trigger events -- clashes bring change, unions bring cohesion, punishments create obstacles, and harms cause hidden damage.
Heavenly Stem Relationships
| Relationship Type | Rule | Primary Effect |
|---|---|---|
| Five Unions | Jia-Ji union to Earth, Yi-Geng union to Metal (5 pairs) | Union-transformation changes the element; binding restrains |
| Clashes | Jia-Geng, Yi-Xin, Bing-Ren, Ding-Gui (4 pairs) | Head-on collision, major upheaval and opposition |
| Controlling | Five Element controlling among Stems (e.g., Jia controls Wu) | One side consumes the other; the stronger prevails |
Earthly Branch Relationships
| Relationship Type | Rule Examples | Energy Level |
|---|---|---|
| Six Unions (Liu He) | Zi-Chou union to Earth, Yin-Hai union to Wood (6 pairs) | Close and cohesive |
| Three Unions (San He) | Shen-Zi-Chen union to Water, Yin-Wu-Xu union to Fire (4 groups) | Powerful convergence |
| Three Gatherings (San Hui) | Yin-Mao-Chen gather Wood, Si-Wu-Wei gather Fire (4 groups) | Strongest convergence |
| Six Clashes (Liu Chong) | Zi-Wu clash, Mao-You clash (6 pairs) | Direct collision |
| Punishments (Xing) | Power-abusing punishment, Ingratitude punishment, Impropriety punishment | Lateral damage |
| Six Harms (Liu Hai) | Zi-Wei harm, Chou-Wu harm (6 pairs) | Covert harm |
| Six Breakings (Liu Po) | Zi-You breaking, Mao-Wu breaking (6 pairs) | Minor breakage |
Stem-Branch Combinations and Whole-Pillar Relationships
- Covering Head (Gai Tou) / Cutting Feet (Jie Jiao) : The Heavenly Stem controls the Earthly Branch (Covering Head) or the Earthly Branch controls the Heavenly Stem (Cutting Feet). Stem and Branch are disharmonious, and strength is constrained.
- Doubled Pillar (Fu Yin) / Reversed Pillar (Fan Yin) : When two pillars are identical, it is Fu Yin (stagnation and amplification). When the Stems clash and Branches clash between two pillars, it is Fan Yin (drastic upheaval).
- Indulge Union, Forget Clash (Tan He Wang Chong) : When two Stems are in a union relationship, they may neglect a simultaneous clash relationship. Priority order of interaction: Union > Clash.
Significance of Relationships in Practical Destiny Analysis
Stem-Branch relationships are the "trigger" in Luck Cycle and Annual Luck analysis -- when a Luck Cycle or Annual Luck forms union, clash, punishment, or harm relationships with the natal chart's Stems and Branches, corresponding life events are often activated. The strength of the relationship determines the intensity of events: Fan Yin / Fu Yin > Six Clashes > Three Unions / Three Gatherings > Six Unions > Punishments and Harms. For detailed conditions and examples of each relationship, please refer to the respective topic entries.