Jiǎ 甲, the yang Wood day master of BaZi

Jiǎ 甲 is the first of the ten Heavenly Stems, yang Wood, and the day master of any BaZi chart whose day stem it is. The 滴天髓 pictures it as wood that reaches the sky and needs fire to come into its own; the 三命通會 as thunder and the dragon in heaven, beams and pillars on earth. As a day master it is rooted in 寅 and 亥 and combines with 己.

Meaning

The 滴天髓 gives each stem a verse of eight short lines. For 甲 it reads, in the 輯要 text:

甲木參天，脱胎要火，春不容金，秋不容土，火熾乘龍，水蕩騎虎，地潤天和，植立千古。

In our translation: Jiǎ wood reaches to the sky; to shed its shell it needs fire. In spring it will not bear metal, in autumn it will not bear earth. When fire blazes it rides the dragon; when water surges it rides the tiger. On moist ground under a mild sky it stands for a thousand ages.

The dragon and the tiger are the branches 辰 and 寅, its refuges when fire blazes and when water surges; the seasons set its limits, and the last line gives the picture of a tree standing for a thousand ages. It is the opening verse of the 滴天髓's chapter on the stems.

The 三命通會 calls 甲 the head of the ten stems: thunder and the dragon in heaven, beams and pillars on earth. In that book's language it is "dead wood" (死木), hard timber that the axe turns into something useful and that still water keeps from rotting. Its sky image is thunder. The 窮通寶鑑 adds that wood rises without stopping and, once it is heavy, wants metal to shape it, deep earth to root in and water in moderation.

Our chart calls 甲 a tall tree: ambitious, upright, visionary and pioneering, with rigidity, a dislike of bending, as its cost. That is EsoTerrier's modern image, the one most English teaching uses, and not the classical meaning; the page shows it beside the texts' own images, each labelled.

In a chart

A 甲 day master has roots wherever 甲 is hidden in a branch: 寅 Yín (main qi), 亥 Hài (middle qi). Its 祿, the branch where its qi comes into office (臨官), is 寅; the branch after it, 卯, is its blade (陽刃). It is born (長生) in 亥 and, as a yang stem, runs the twelve stages forward from there; the stages are phases of its qi.

It combines with 己 Jǐ (天干五合), a pair the 三命通會 calls 中正之合 (the match of the central and upright), leaning to Earth; it clashes with 庚 Gēng. Its own phase is strongest in spring.

To a 甲 day master the ten stems are: 甲 Friend (比肩); 乙 Rob Wealth (劫財); 丙 Eating God (食神); 丁 Hurting Officer (傷官); 戊 Indirect Wealth (偏財); 己 Direct Wealth (正財); 庚 Seven Killings (七殺); 辛 Direct Officer (正官); 壬 Indirect Resource (偏印); 癸 Direct Resource (正印). A second 甲 elsewhere in the chart is a Friend; the day stem itself is the Day Master and is not one of the Ten Gods.

What this page leaves out

The classical chapters on 甲 also say, in the idiom of their age, what such a chart means for rank, kin, marriage and fortune. We record that they do and repeat none of it. Nor do we say whether a 甲 day master is strong or weak, or which useful god it needs: the tradition weighs both, and EsoTerrier computes neither.

Correspondences

Each item with how it stands: “sourced” is in the work cited, “our construction” is EsoTerrier’s own, and “disputed” means the sources disagree.

Opening of the 滴天髓 verse: 「甲木參天」 sourced
Sky image, 三命通會: Thunder (雷) sourced
In heaven and on earth, 三命通會: In heaven thunder and the dragon, on earth beams and pillars (在天為雷為龍，在地為梁為棟) sourced
The first month, 窮通寶鑑: Wood rises without stopping; when heavy it wants metal to shape it; it loves deep earth to root in and water in moderation (論木) sourced
Combination, 三命通會: With 己: 中正之合 (the match of the central and upright) sourced
Nobleman star (天乙貴人): 丑 and 未; a symbolic star we do not chart yet sourced
Academic star (文昌): 巳; a symbolic star we do not chart yet sourced
Our image, traits and challenge: Tall tree: ambitious, upright, visionary and pioneering; its challenge: rigidity, and a dislike of bending our construction
Tall tree as the classical meaning: A modern image; the classics give the ones above disputed
First meaning of the character: Uncertain; the stems are first attested as day names of the Shang week disputed

How the schools read it

滴天髓, the verse: Wood that reaches the sky and needs fire; its limits set by the seasons and its refuges by the branches. Attributed to 京圖 of the Song or to Liu Bowen; one edition study dates the text mid-Ming or later.
任鐵樵, 滴天髓闡微 (after 1820): Prints the same verse with 水宕騎虎 for 水蕩騎虎, with the same sense.
三命通會 (Ming): The head of the stems; thunder and the dragon, beams and pillars; dead wood that the axe makes useful.
窮通寶鑑 (Qing): Wood that rises without stopping and wants metal to shape it once it is heavy.
Modern English teaching: The one-word image, a tall tree, a simplification of the classical images.
EsoTerrier: Shows a tall tree as its own image, labelled, beside the texts.

Claims about it

"Tall tree" is the traditional meaning of 甲.
disputed

What the record shows: It is a modern teaching image, and ours on the chart. The 滴天髓 has wood that reaches the sky; the 三命通會 has thunder, the dragon, beams and pillars.
The day stem is itself a Ten God, the Friend (比肩).
false

What the record shows: A 甲 in another pillar is a Friend to a 甲 day master; the day stem itself is the reference point, labelled Day Master (日主) by every tool we surveyed.
A 甲 day master can be scored strong or weak, and its useful god computed.
disputed

What the record shows: The classics ground the useful god in at least four different ways. EsoTerrier computes neither the strength nor the useful god.
The classical chapters on 甲 tell a person's rank, marriage and length of life.
told as lore

What the record shows: The texts do make such pronouncements, in the idiom of their age. We take only their images and the logic of the phases.

Elsewhere on EsoTerrier

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Jiǎ 甲, yang Wood: the tree that reaches the sky

Facts