The Letters of the Chart
Every Four Pillars chart is written in the same alphabet: Heavenly Stems and Earthly Branches. Ten Stems. Twelve Branches. Combined, they create a sixty-unit cycle that has been in continuous use for over 3,000 years.
Before you can read your chart, you need to know the letters.
The Ten Heavenly Stems
The Stems are the five elements expressed in Yin and Yang pairs. Ten total: 甲 Jiǎ (Yang Wood, the tall tree), 乙 Yǐ (Yin Wood, the vine), 丙 Bǐng (Yang Fire, the sun), 丁 Dīng (Yin Fire, the candle), 戊 Wù (Yang Earth, the mountain), 己 Jǐ (Yin Earth, the garden soil), 庚 Gēng (Yang Metal, the axe), 辛 Xīn (Yin Metal, the jewel), 壬 Rén (Yang Water, the ocean), 癸 Guǐ (Yin Water, the dew).
Your Day Master is one of these ten stems. That stem is the most condensed description of your constitutional nature in the entire system.
The Stems represent heaven's influence — the quality of energy present. They tell you what kind of energy is in each pillar.
The Twelve Earthly Branches
The Branches are the twelve positions in the cycle. They carry their own elemental associations, but they're more complex than the Stems because each Branch contains hidden elements inside it.
子 Zǐ (Rat, Yang Water, deep winter), 丑 Chǒu (Ox, Yin Earth, late winter), 寅 Yín (Tiger, Yang Wood, early spring), 卯 Mǎo (Rabbit, Yin Wood, mid spring), 辰 Chén (Dragon, Yang Earth, late spring), 巳 Sì (Snake, Yin Fire, early summer), 午 Wǔ (Horse, Yang Fire, mid summer), 未 Wèi (Goat, Yin Earth, late summer), 申 Shēn (Monkey, Yang Metal, early autumn), 酉 Yǒu (Rooster, Yin Metal, mid autumn), 戌 Xū (Dog, Yang Earth, late autumn), 亥 Hài (Pig, Yin Water, early winter).
The Branches represent earth's influence — the environment, the timing, the grounding. They tell you where and when the energy operates.
Notice the four Earth branches (丑辰未戌) are spaced evenly through the year, one per season-transition. Earth is the mediator between seasons. It doesn't have its own season. It governs the transitions between all of them.
How Stems and Branches Combine
A Stem and a Branch pair together to form a pillar. Your chart has four pillars: Year, Month, Day, Hour. Each pillar is one Stem sitting on one Branch.
The Stem is the visible quality. What people see. The outward expression. The Branch is the hidden foundation. What's underneath. The root system.
When people say "I'm a Dragon" based on their birth year, they're naming only the Branch of their Year Pillar. That's one piece of one pillar out of four. It's like describing a building by naming the material of one corner of the foundation. Not wrong. Not enough.
The Sixty-Year Cycle
← How Stems and Branches Combine
Ten Stems cycling against Twelve Branches creates a combined cycle of sixty unique Stem-Branch pairs. This is the sexagenary cycle (六十甲子), and it has been used continuously since at least the Shang Dynasty — over 3,000 years of unbroken record.
The cycle begins at 甲子 (Yang Wood Rat) and ends at 癸亥 (Yin Water Pig), then repeats. Every year, every month, every day, every two-hour period has its own Stem-Branch designation. This means the exact combination of four Stem-Branch pairs at the moment of your birth is astronomically specific.
Your chart is, in this sense, a timestamp. An extremely precise one. The Stems and Branches are the units of measurement.
Branch Relationships
The Branches don't just sit in their positions. They interact with each other through specific relationships:
Six Harmonies 六合: Certain Branch pairs combine to produce a new elemental energy. These combinations modify what the chart actually expresses.
Three Harmonies 三合: Groups of three Branches form elemental teams. 申子辰 form the Water frame. 寅午戌 form the Fire frame. 巳酉丑 form the Metal frame. 亥卯未 form the Wood frame. When these three Branches appear together in a chart, that element becomes dominant.
Clashes 六冲: Certain Branch pairs oppose each other. 子午 clash (Water vs Fire). 卯酉 clash (Wood vs Metal). Clashes create tension, disruption, and forced change. Not always bad — sometimes a clash is what breaks a logjam.
Penalties 刑: Certain Branch combinations create friction through what the classical texts call punishments. These are subtler than clashes — less explosive, more grinding. Self-punishment (the same Branch appearing twice, like 辰辰) is a form of internal friction.
Harms 害: Certain Branch pairs undermine each other quietly. Less dramatic than a clash, more corrosive over time.
These relationships are tracked in your chart because they tell you where energy flows smoothly and where it creates friction.
Why This Matters
The Stems and Branches are not decorative labels. They are the data. Every analysis in BaZi — every Ten God calculation, every decade reading, every compatibility assessment — starts by reading the Stems and Branches and understanding how they interact.
You don't need to memorize all sixty combinations. You need to know that your chart is written in this alphabet, that each character carries specific elemental and polarity information, and that the interactions between characters create the dynamics of your life.
The alphabet came first. Everything else is built on top of it.