The Twelve Day Officers — Jianchu Method (建除十二神擇日法)
The Jianchu (建除) system, also known as the Twelve Day Officers (十二建除神) or Twelve Value Gods (十二值神), is the oldest and most fundamental date selection framework in Chinese calendar science. It assigns one of twelve 'officers' to each day based on the relationship between the month's Earthly Branch and the day's Earthly Branch. This system forms the backbone of every traditional Chinese almanac (Tong Shu).
The Twelve Officers
The twelve officers cycle continuously, one per day, following a fixed sequence:
- 建 (Jian — Establish): Setting foundations. Good for leadership actions, initiating projects. Avoid marriages, lawsuits. Black Path (黑道).
- 除 (Chu — Remove): Clearing obstacles. Excellent for medical treatment, cleansing, demolition. Yellow Path (黃道).
- 滿 (Man — Full): Fullness, completion. Good for harvest, receiving goods, celebrations. Avoid starting new ventures. Yellow Path.
- 平 (Ping — Balance): Equanimity, neutrality. Acceptable for routine activities. No strong bias. Black Path.
- 定 (Ding — Settle): Stability, fixedness. Excellent for ceremonies, contracts, agreements. Avoid travel, moving. Yellow Path.
- 執 (Zhi — Grasp): Control, enforcement. Good for construction, building. Avoid legal disputes. Yellow Path.
- 破 (Po — Break): Destruction, breaking apart. Universally avoided for auspicious activities. Only suitable for demolition. Black Path.
- 危 (Wei — Danger): Precariousness, risk. Good for religious activities, offering prayers. Avoid construction, travel. Yellow Path.
- 成 (Cheng — Accomplish): Achievement, completion. One of the best officers — excellent for business, contracts, marriage. Yellow Path.
- 收 (Shou — Receive): Collection, gathering. Good for receiving payments, harvesting, concluding deals. Black Path.
- 開 (Kai — Open): New beginnings. Excellent for opening businesses, starting construction, weddings. Yellow Path.
- 閉 (Bi — Close): Closure, completion. Good for burial, storage, ending activities. Avoid starting new things. Black Path.
Derivation from Month Branch
The assignment follows a precise rule: the officer 建 (Establish) always falls on the day whose Earthly Branch matches the current month's Earthly Branch. For example, in a Yin (寅) month (roughly February), every Yin (寅) day is a 建 day. The subsequent officers follow in the fixed sequence above, advancing one position per Branch.
Formula: Officer Index = (Day Branch Index − Month Branch Index + 12) mod 12, mapped to the sequence [建, 除, 滿, 平, 定, 執, 破, 危, 成, 收, 開, 閉].
Yellow Path and Black Path (黃道 · 黑道)
The twelve officers are divided into two groups:
- Yellow Path (黃道) — Auspicious officers: 除, 滿, 定, 執, 危, 成, 開 (7 officers)
- Black Path (黑道) — Inauspicious officers: 建, 平, 破, 收, 閉 (5 officers)
Yellow Path days are preferred for important activities. Black Path days require additional positive factors (auspicious Shen Sha, favourable Dong Gong grade) to be considered usable.
Divine Spirits (十二值神之神)
Each officer is associated with a presiding divine spirit:
- 建 → 青龍 (Blue Dragon) | 除 → 明堂 (Bright Hall) | 滿 → 天刑 (Heaven's Punishment) | 平 → 朱雀 (Vermilion Bird)
- 定 → 金匱 (Golden Chest) | 執 → 天德 (Heaven's Virtue) | 破 → 白虎 (White Tiger) | 危 → 玉堂 (Jade Hall)
- 成 → 天牢 (Heaven's Prison) | 收 → 玄武 (Dark Warrior) | 開 → 司命 (Life Controller) | 閉 → 勾陳 (Hook Array)
Officer-Stem Interaction
Advanced practitioners also consider the interaction between the day officer and the day's Heavenly Stem. Certain stem-officer combinations amplify or diminish the officer's inherent quality. For example, a 成 (Accomplish) day with a Yang stem (甲, 丙, 戊, 庚, 壬) is considered stronger than one with a Yin stem, because Yang energy supports the accomplishing nature of the officer.
Integration with Activity Types
Each officer has specific activity affinities:
- Marriage: Best — 成, 開, 定. Avoid — 破, 閉, 建.
- Construction: Best — 執, 成, 開. Avoid — 破, 收.
- Business Opening: Best — 開, 成, 滿. Avoid — 破, 閉.
- Moving House: Best — 除, 成, 開. Avoid — 破, 建, 閉.
- Burial: Best — 閉, 定, 成. Avoid — 破, 建, 開.