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Day Pillar 42 of 60 · Nayin Lamp Flame Fire

Yi Si (乙巳) Day Pillar — Yin Wood on the Snake

The Yi Si day pillar pairs the Yi day master (Yin Wood) with the Si branch (Fire, the Snake). Below: the computed facts, what the seat relation and twelve-stage position mean structurally, the nayin gloss, the classical reading of the spouse palace, and an instant lookup for your own pillar.

Computed facts (engine-verified)

This page is generated from the engine, not hand-written; structural facts reconcile against the methodology page.

Day master乙 Yi · Yin Wood
Day branch巳 Si (Snake) · Fire
Hidden stems丙 Bing (Hurting Officer, main qi); 庚 Geng (Direct Officer, middle qi); 戊 Wu (Direct Wealth, residual)
Stage of the stem hereBathing (2 of 12)
NayinLamp Flame Fire · 覆灯火 (shared with Jia Chen 甲辰)
Seat relationStem generates branch (xie) — traditional term: 泄

How Yi sits on Si

The stem generates the branch: Wood flows into Fire, so the Yi day master sits on ground that continuously draws its output. Traditional wording calls this 泄 (xiè, "draining") — the self is spent into its own base. Again this is a statement of flow, not of fortune: the day master's energy has a standing outbound channel right under it, and the rest of the chart decides whether that channel is a liability or a productive one.

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Nayin: Lamp Flame Fire

Lamp Flame Fire (覆灯火): lamp fire — flame under a cover, light for one room. The classical reading is focused, domestic illumination.

The spouse palace (day branch)

In the spouse palace this is an Output (食伤) configuration: the classical reading treats the partner-side branch as the place where the Yi day master expresses rather than absorbs. The structural point — stated by the tradition, not by this site — is that intimacy here runs through expression and making. Whether that lands well in an actual relationship depends on the other seven characters, which is why this page stops at structure.

The main qi 丙 (Bing, Hurting Officer) defines the palace's classical group: Output. Middle/residual tenants: Geng (Direct Officer), Wu (Direct Wealth).

A note on what this page deliberately does not do: the internet is full of "60 personality types" tables that assign a fixed character to each day pillar. This site rejects that framing. A day pillar is a structural position — who sits where, on what kind of ground, with which hidden tenants. The same pillar reads differently under a different month command, and no meaningful judgement exists without the other six characters. Where the tradition offers a reading, it is labelled as the tradition's; this site's own contribution is that every number and term on this page is computed, versioned, and checkable against the methodology page.

Find your own day pillar

Birth date alone is enough — the day pillar never needs a birth time. The calculation runs in your browser; nothing is sent anywhere.

Frequently asked

What is the Yi Si (乙巳) day pillar?
The Yi Si day pillar pairs the Yi stem (Yin Wood) with the Si branch (Fire). Its computed facts: hidden stems Bing (Hurting Officer), Geng (Direct Officer), Wu (Direct Wealth), the Yi stem at the Bathing stage on this branch, seat relation "undefined", and nayin Lamp Flame Fire (覆灯火).
How do I find my own day pillar?
Use the calculator on this page (birth date is enough — the day pillar does not need a birth time) or the full chart calculator. Your day pillar is the third pillar of the four; each of the sixty has its own page on this site with the same computed structure.
Is the Yi Si day pillar good or bad?
Neither, on its own. The seat relation (undefined) and the Bathing stage describe position and flow, not fortune. A meaningful reading needs the month command and the other six characters — any source that grades pillars as lucky or unlucky is simplifying past what the system itself claims.
What does the nayin Lamp Flame Fire mean?
Nayin (覆灯火) is a two-thousand-year-old classification that gives each PAIR of pillars a symbolic element-image — for Yi Si it is "Lamp Flame Fire", shared with its partner pillar Jia Chen (甲辰). It is a classical gloss layer, published here alongside the structural facts, never instead of them.

Nearby pillars

The other five pillars sharing this day master (Yi):

Yi Chou · Yi Hai · Yi You · Yi Wei · Yi Mao

Jia Chen ←  ·  → Bing Wu

Reference index

Every enumerable component of ba zi has its own page here. Each page is computed by the same engine and can be checked item by item — none of it is a personality table.