Day Pillar #12 · 乙亥
| Position in the cycle | #12 of 60 |
|---|---|
| Heavenly stem 天干 | 乙 — 木 Wood |
| Earthly branch 地支 | 亥 — 水 Water |
| Nayin 纳音 | 山头火 — Mountain-Top Fire (Fire) |
| Hidden stems 藏干 | 壬、甲 — 壬 (Water), 甲 (Wood) |
| Twelve-stage placement 十二长生 | 死 — Death (of the stem in its own branch) |
Yihai (乙亥) is the first pillar in this series where two completely different systems inside the tradition arrive at the same sentence.
Di Tian Sui on yin wood gives four conditions in eight characters each. The one that matters here:
乙木虽柔，刲羊解牛。怀丁抱丙，跨凤乘猴。虚湿之地，骑马亦忧。藤萝系甲，可春可秋。
Yi wood, though soft, can still butcher the ox and slaughter the sheep. Holding Ding and embracing Bing, it rides the Rooster and mounts the Monkey unharmed. But in ground that is hollow and damp, even riding the Horse it worries. Vine bound to the tree, it can stand through spring or autumn alike.
The commentary is unusually specific about what "hollow, damp ground" means: born in the water months, with no Bing or Ding fire in the chart and no dry earth either, then even having the Horse branch present will not produce growth. 亥 is that hollow damp place by name.
Nayin is the sound element of the paired pillar — a separate layer that ignores stem logic entirely. 甲戌 and 乙亥 together are mountain-top fire, glossed as 内明外暗，隐而不显 — bright within, dark without, hidden and not shown. On this pillar specifically, San Ming Tong Hui writes:
乙亥，伏明之火。其气湮郁而不发，借己亥、辛卯、己巳、壬午发。
Yihai, the fire of hidden brightness. Its energy is choked up and does not come out; it borrows Jihai, Xinmao, Jisi or Renwu in order to emerge.
Two unrelated methods, one result. The problem with this pillar was never an absence of fire. It is fire that is present and cannot get out.
And both texts then do the thing that keeps showing up in the good sources: they give a condition, not a verdict. The stem line's answer is Bing or Ding showing, or dry earth to stand on. The nayin passage lists precisely which pillars let it come out. Neither says lucky, neither says doomed. They say: here is what is missing, go look for it.
Sources: 《三命通会》 (San Ming Tong Hui, Ming, 万民英) and 《滴天髓》 (Di Tian Sui) — both quoted from local plain-text editions and verified character by character. Translations are ours. Corrections are welcome.
Enter a birth date and time to get the four pillars, the hidden stems, the nayin and the twelve-stage placements for a real chart — the same tables this page is built on.
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