Yi 乙, the Yin Wood Day Master

Not a smaller tree: the picture of 乙

It is tempting to read yin wood as a weaker yang wood. The classics don’t. 三命通會 calls 乙 wind in the sky and trees on the ground, and at its home branch, 卯, trees with deep roots and thriving branches, which it calls living wood (活木), soft and alive. It sets that against 甲, timber that needs an axe before it is any use (三命通會, vol. 2). The commentary under 滴天髓’s verse calls 乙 the wood of branches and leaves, “soft like flowers and plants” (滴天髓, 天干論).

Korean teaching keeps the picture and adds the part people remember: 을목 is flowers, weeds, grass and moss, the plant that grows anywhere and comes back after it has been pulled up or cut (정해 만세력 lecture 05). As a temperament, readers describe 乙 as adaptable and persistent, better at finding a way around a wall than through it, and more tuned to the people around it than 甲 tends to be. On a team, 乙 is often the connector who knows whom to ask; up close, it adjusts to other people’s rhythms so readily that its own preferences can go unsaid.

A verse full of animals: 乙 among the elements

滴天髓’s line for 乙 reads like a tour of the zodiac: 乙木雖柔，刲羊解牛，懷丁抱丙，跨雞乘猴. Soft as it is, yin wood can carve up the goat and take apart the ox; holding 丁 and embracing 丙, it rides the rooster and the monkey (滴天髓, 天干論). The animals are branches, and each is an element meeting 乙.

• Earth, the goat and the ox (未 and 丑): the commentary says that sitting on 丑 or 未, soft yin earth, 乙 masters it “like slaughtering a sheep or carving an ox.” Earth is 乙’s wealth, with 戊 in the role of Direct Wealth and 己 in that of Indirect Wealth. Read as temperament, 乙 handles practical ground, money and logistics better than its gentle image suggests.
• Fire, held and embraced: this is 乙’s output, 丁 the gentler Eating God, 丙 the sharper Hurting Officer. With a single 丙 or 丁, the commentary says, 乙 isn’t afraid even in the metal months of 申 and 酉, the monkey and the rooster. So expression is 乙’s armor: a 乙 that makes, speaks and shows its work tends to stand up to pressure better than one that stays quiet.
• Metal, the rooster and the monkey: to 乙, 庚 means Direct Officer and 辛 means Seven Killings, and 三命通會 says 乙 fears yang metal chopping it down. Yet 乙 pairs off with 庚 in a stem combination, and 滴天髓’s own verse for 庚 says it beats its elder brother 甲 but loses to its younger sister 乙 (輸於乙妹). In people, that looks like dealing with authority through relationship rather than force, and often coming out ahead that way.
• Water, and the damp ground: water feeds wood, so 壬 and 癸 are 乙’s resources (Direct Resource and Indirect Resource). 三命通會 wants “living water,” rain and dew, for 乙’s leaves, but 滴天髓 warns that in the 子 month, with metal and water showing, even the horse, 午, can’t bring it to life: 虛濕之地，騎馬亦憂. Support helps 乙 in doses; too much comfort and advice tends to leave it damp and slow.
• Wood, the vine and the tree: a second 乙 is a Friend, while 甲, the tree it climbs, is Rob Wealth. The verse closes 籐蘿繫甲，可春可秋: wisteria tied to 甲 does well in spring or autumn. A 乙 person often grows best beside something sturdier, a mentor, a team or an institution, and there is no weakness in saying so.

The Korean angle: 을, the second party

Outside saju, 을 (eul), the Korean reading of 乙, has a life of its own: in everyday Korean it is the second party to a contract, the one without the upper hand, set against 갑 (Korea Herald; Wikipedia: Gapjil).

The classical picture of 乙 is a good answer to that. The vine is the forest’s second party, and the classics still give it the win over 庚 that 甲 can’t get, by combining rather than fighting. In the tradition’s terms, a 乙 Day Master often does its best work from the position that looks smaller: the adviser, the negotiator, the person everyone quietly routes decisions through.

乙 last headed a year in 2025, 乙巳. By the Korean color rule, wood’s color is 청, blue-green, so it was a year of the Blue Snake, 푸른 뱀 (색, E0027476).

The ten gods, seen from 乙

Change the Day Master from 甲 to 乙 and every relation flips polarity. What is 甲’s Direct Wealth (己) is your Indirect Wealth; 甲’s Seven Killings (庚) is your Direct Officer. That is why the two wood Day Masters read so differently with the same elements around them.

Six days that carry 乙

乙 sits only on yin branches, so its six pillars are 乙丑 Wood Ox, 乙亥 Wood Pig, 乙酉 Wood Rooster, 乙未 Wood Goat, 乙巳 Wood Snake and 乙卯 Wood Rabbit. Two of them are the goat and the ox of the verse, 乙未 and 乙丑, the days on which the commentary says 乙 masters its earth. 乙卯 is 乙 on its own branch, at 建禄 (steady self-reliance).

乙亥 is where 三命通會 places the “death” of 乙: the tenth month, 亥, when “water floods and the wood floats” (水泛木浮) (三命通會, vol. 2). Our twelve-stage table agrees (死). That is the life-cycle metaphor at work, and the day-pillar page reads 乙亥 as the reed on the winter river, not as a warning.

2027 (丁未) for a Yi Day Master

Few Day Masters find as much of their own verse in 丁未 as 乙. The year stem is your Eating God, the easygoing, making kind of output, and 未 is the goat that 滴天髓 says 乙 can carve up: its main stem 己 is your Indirect Wealth, with 丁 and your own stem 乙 inside it. On the twelve-stage wheel, 未 is where 乙 sits at 養 (being looked after).

Put enjoyment and craft (Eating God) next to resources that move among many people (Indirect Wealth), and a vine sees an invitation to say yes: to the favor, the new circle, the extra shift. Horan’s question for 乙 is simple. Which of those yeses feeds your roots, and which only adds leaves? It’s a question to sit with, and it doesn’t describe events; all ten Day Masters in 2027 are on the year page.

About this page

Written with AI (Claude) from the sources listed and our calculation engine. Horan and Kachi are fictional characters, and nothing here predicts events. The rules behind every chart: how we calculate.