Yin (寅) Earthly Branch: the Tiger, Yang Wood, and What It Means in Your Bazi Chart

The Tiger is the branch that kicks the Chinese year into motion. While the Rat (Zi) marks midnight and the Ox (Chou) grinds through the frozen tail end of winter, it is the Tiger — Yin (寅) — that throws the door open. Spring begins here. The year begins here. And buried inside this one character is not just Wood, but a hidden seed of Fire and a trace of Earth, making Yin one of the richest branches in the entire cycle.

一 What Yin (寅) Actually Is

Yin 寅 is the third of the twelve [[Earthly Branches]], and it carries Yang Wood as its native element. Its animal symbol is the Tiger, and its polarity is [[Yang]] — active, outward, initiating. For the underlying framework, see Earthly Branches in Bazi: The Twelve Characters and Their Hidden Stems.

What gives Yin its depth is the three [[Hidden Stems]] packed inside it:

Three elements in one branch, all of them yang. The main qi is 甲 Jiǎ — the strongest Wood stem, the tall timber tree. But the middle qi, 丙 Bǐng Fire, is what makes Yin special in the classical system. Fire reaches its long-life stage (长生) in Yin, meaning this is where Fire is born. Wood carries Fire inside itself the way a log carries the heat it will one day release. The residual qi, 戊 Wù Earth, adds a grounding note — the ash left after Fire has done its work.

Seasonally, Yin governs the first solar month, running from 立春 (Lǐchūn, Start of Spring) to 惊蛰 (Jīngzhé, Awakening of Insects) — roughly early February to early March. This is not merely the start of spring; it is the start of the Chinese calendar year itself. Every annual pillar turns over at Lǐchūn, and it is the Yin branch that receives the new year's energy first. The Tiger hour runs from 03:00 to 05:00, the time just before dawn when the sky begins to lighten.

The classical image: wood breaking through frozen ground, carrying fire inside it like a seed of warmth — the first stirring of spring after a long winter.

二 Where to Find Yin in Your Chart

Your [[Four Pillars]] chart is a grid of four columns — Year, Month, Day, and Hour — each with a [[Heavenly Stem]] on top and an Earthly Branch on the bottom. Yin can appear in the branch row of any of those four positions.

• Yin as year branch means you were born in a Tiger year (2022, 2010, 1998, 1986, 1974 …).
• Yin as month branch means you were born during the first solar month — the opening stretch of spring, between Lǐchūn and Jīngzhé. Because this is the month that launches the Chinese year, a Yin month branch carries a strong association with new beginnings.
• Yin as day branch is determined by the sixty-pillar [[Jiazi]] cycle and cannot be guessed from the calendar date alone. It repeats every twelve days.
• Yin as hour branch means you were born between 03:00 and 05:00 in [[true solar time]] (adjusted for your birth longitude, not clock time).

三 How to Read Yin

With three hidden stems, Yin never plays a single role in a chart. It delivers Wood, Fire, and Earth simultaneously, each at a different weight. The practical question is always: how do those three hidden stems relate to your [[Day Master]]? The method is easier to compare with Chou (丑) Earthly Branch: the Ox, Yin Earth, and What It Means in Your Bazi Chart.

The hidden stems and your Day Master

The main qi, 甲 (Jiǎ Wood), is the loudest voice inside Yin. This is the same stem that a Jiǎ Day Master calls its own element — the full-sized timber tree, strong and upright. At weight 1.0, it arrives with full force.

The middle qi, 丙 (Bǐng Fire), means Yin is never cold Wood. Even in early spring, this branch carries warmth. At weight 0.5, Fire is present but secondary — enough to matter in the tally, not enough to dominate.

The residual qi, 戊 (Wù Earth), adds a grounding trace at weight 0.3. Earth is Wood's output in the control cycle (Wood controls Earth), so Yin contains the seed of what its own Wood element is meant to shape.

Here is how those three stems translate into [[Ten Gods]] for a few common Day Masters:

Because all three hidden stems are yang, they always land on the same-polarity side of the ten god pairs for a yang Day Master (Friend, Eating God, Indirect Wealth, Seven Killings, Indirect Resource) and on the opposite-polarity side for a yin Day Master ([[Rob Wealth]], [[Hurting Officer]], [[Direct Wealth]], [[Direct Officer]], [[Direct Resource]]).

Pillar position matters

• Year pillar — Ancestry, early life, and the family's outward energy. Yin in the year branch often describes a family with initiative and ambition — people who started things.
• Month pillar — Career and social standing. Yin as month branch means you were born in the first solar month, the very start of the year. This is the most seasonally potent placement: Wood is freshly in season, Fire is being born, and the energy is all about forward movement and new ventures.
• Day pillar — Self and spouse. The day branch is the [[Spouse Palace]], so Yin here colours the marriage dynamic with independence, warmth, and a partner who does not sit still.
• Hour pillar — Children, aspirations, and the final chapter of life. Yin in the hour branch points toward an active late life and children with a pioneering streak.

Wherever Yin appears, it brings a forward-leaning energy. This is the branch of initiation — the first month, the first light before dawn, the first green shoot through hard ground. A chart with Yin in it is rarely passive.

四 When Yin Plays Out Differently

A branch never operates alone. Yin's behaviour shifts depending on which other branches sit nearby in the chart or arrive through [[Luck Pillars]] and annual pillars. This point connects directly with Mao (卯) Earthly Branch: the Rabbit, Yin Wood, and What It Means in Your Bazi Chart.

1. Yin-Hai (寅亥) Six Harmony → transforms toward Wood

When Yin meets [[Hai]] (Pig, Water), the two form a [[Six Harmony]] pair that pulls toward Wood. Hai's main hidden stem 壬 (Water) feeds Yin's main hidden stem 甲 (Wood) — Water producing Wood in the most direct way possible. If your chart already has strong Wood, this combination amplifies it further. For a Wood Day Master, Yin-Hai harmony means the support network (Water) and the self (Wood) are working in lockstep, which can be a tremendous asset or a recipe for excess depending on what the rest of the chart needs.

2. Yin-Wu-Xu (寅午戌) Three Harmony → Fire Bureau

Yin joins [[Wu]] (Horse) and [[Xu]] (Dog) to form the [[Three Harmony]] Fire frame. This is where Yin's hidden 丙 comes alive. In the twelve-stage growth cycle, Fire is born in Yin (长生), peaks in Wu (帝旺), and is stored in Xu (墓库). When all three branches appear together, Fire energy surges across the chart. The Wood of Yin feeds the Fire of Wu, and Xu locks the result into storage. This is the strongest Fire formation the branch system can produce, and Yin is its starting point — the place where Fire first draws breath.

3. Yin-Shen (寅申) Clash → Wood and Metal in head-on collision

Yin (Wood) and [[Shen]] (Monkey, Metal) sit directly opposite each other in the branch circle, forming a [[Six Clash]]. This is one of the most active clashes in the system. Both branches are yang, both carry three hidden stems, and the collision sends shockwaves across multiple elements simultaneously: Yin's 甲 Wood clashes with Shen's 庚 Metal (the classic Metal-chops-Wood conflict), Yin's 丙 Fire attacks Shen's 庚 Metal (Fire melting Metal), and Yin's 戊 Earth meets Shen's 戊 Earth (a neutral standoff). The result is a high-energy disruption that shakes loose whatever the involved pillar positions represent.

4. Yin-Si-Shen (寅巳申) Punishment → the punishment of ingratitude

The Yin-Si-Shen triangle forms the 无恩之刑 — the [[punishment]] of ingratitude. Fire is born in Yin, matures in [[Si]] (Snake), and the Metal of Shen tries to control the Wood of Yin. The classical reading is that a natural progression gets disrupted by competing agendas: what should be a smooth handoff of energy (Wood → Fire → Metal in the production cycle) turns into a three-way tangle where each branch undermines the one that gave it life. Even a partial version — just Yin-Si or Yin-Shen in adjacent pillars — can trigger this dynamic.

5. Yin-Si (寅巳) Harm → hidden stems pulled into conflict

Separately from the punishment, Yin and Si also form a [[Six Harm]] pair. The harm operates differently from a clash: instead of a head-on collision, it is a sideways pull that drags the hidden stems of both branches into friction. Yin's 甲 Wood feeds Si's 丙 Fire (productive on the surface), but Si's hidden 庚 Metal turns around and attacks Yin's 甲 Wood. The result is a relationship where giving and taking happen simultaneously — support that comes with a cost, generosity that generates resentment.

五 Real Charts

Chart A — Yin in month branch, partial Fire three harmony

Yin sits in the month pillar — the career and social position house — and its hidden 甲 (Friend) tells us the Day Master has a natural ally embedded right where it matters most professionally. The month stem 庚 (Seven Killings) sits on top of Yin, creating a stem-branch tension that the classical texts call "Metal sitting on Wood" — the controlling element perched above the element it controls. In practice, this often reads as external pressure or authority directly bearing down on the Day Master's support network.

The year branch 午 (Horse) forms two-thirds of the Fire three harmony (寅午戌) with month branch Yin — only 戌 (Xu) is missing. Even without completing the full trio, the partial Fire presence is strong. The visible stem 丙 plus Yin's hidden 丙 plus Wu's hidden 丁 give Fire a combined weight of 2.5 across the chart. If a 戌 Xu arrives through a luck pillar or annual pillar, the three harmony locks in and Fire becomes the chart's dominant force.

The two 辰 branches in the day and hour positions pile up Indirect Wealth (戊) — three separate pockets totalling 3.3, making it the chart's strongest ten god by far. This is a person whose chart is saturated with wealth potential, but who needs the discipline of 庚 (Seven Killings) and the creative outlet of Fire (Eating God and Hurting Officer) to convert that potential into something tangible.

Chart B — Yin-Hai six harmony with abundant Wood

Yin appears twice — in both the month and hour branches — and the year branch 亥 (Hai, Pig) forms a six harmony with month branch Yin (寅亥合木). That combination transforms toward Wood, pouring even more Wood energy into a chart that is already saturated with it. The visible stems reinforce the theme: 甲 in the month and 甲 as the Day Master, with 癸 (Direct Resource, Water) in the year stem feeding them both.

The Friend total of 3.5 is extraordinary. The Day Master is surrounded by its own element on nearly every side — the hidden 甲 inside both Yin branches (1.0 each) plus the one inside Hai (0.5) plus the visible month stem 甲 (1.0). The classical reading for this much Friend energy is a person who has enormous self-reliance and initiative but who struggles with competition and with sharing resources, because the same element that strengthens the self also crowds the space around it.

Meanwhile, the Water-produces-Wood chain runs unbroken from year through month: 亥 hides 壬 (Indirect Resource) and 甲 (Friend), and the visible 癸 on top adds Direct Resource. The only significant outlet for all this accumulated Wood energy is Fire. The day branch 午 (Horse) sits in the middle of the chart as the lone Fire branch, and its hidden 丁 (Hurting Officer) is the main exhaust valve. The hour stem 丙 (Eating God) helps, but without more Fire or Metal elsewhere, this chart risks becoming a forest with too few clearings.

六 How Common Yin Is

Across all 518,400 possible Four Pillars combinations, Yin (寅) appears as the day branch in 43,200 charts (8.3%), as the month branch in another 43,200 (8.3%), and in at least one of the four branch positions in approximately 152,375 charts (29.4%). These figures are identical for every earthly branch — the sixty Jiazi cycle distributes them evenly. Having Yin in your chart is not rare or special in itself; what matters is where it sits, what it meets, and how its three hidden stems interact with your Day Master.