What Is Yuan Chen / Great Depletion (元辰) in BaZi?
Learn Yuan Chen’s two lookup directions, why year polarity and the historical sex class matter, and the limits of OpenFate’s current single-table output.
Overview
Yuan Chen, also called Great Depletion in some translations, is derived from the branch opposite the natal year branch and then moved one place forward or backward according to a historical yin-yang-year and sex classification. The two directions must not be collapsed into one universal table.
At a glance
- Pivot
- Natal year branch
- First step
- Find the opposite branch
- Yang-man / yin-woman rule
- Move one place forward
- Yin-man / yang-woman rule
- Move one place backward
- Classical aliases
- 毛頭星 · 大耗
- OpenFate engine
- Current auxiliary output uses one direction only
The two-direction year-branch rule
San Ming Tong Hui starts from the branch opposite the natal year branch. For the historical “yang man / yin woman” class it moves one branch forward; for the “yin man / yang woman” class it moves one branch backward. A Jia-Zi man, for example, takes Wu as the opposite of Zi and then Wei as Yuan Chen.
The paired example for an Yi-Chou man moves from Chou’s opposite, Wei, backward to Wu. These examples show why one year-branch table cannot reproduce both branches of the classical method.
- Determine year-stem polarity and the declared rule branch first.
- Find the opposition before moving forward or backward once.
Why simplified tables need a method label
The source records competing songs and scholarly explanations rather than pretending that every table agrees. Some modern lists omit the polarity-and-sex split, but doing so changes the algorithm and should be identified as a simplified version.
The historical binary categories are computational conventions from the source, not evidence about modern gender identity, expression, sexuality, or personality. A product that asks for such an input must explain what the field controls and offer an honest boundary.
- Name the table version instead of merging variants silently.
- Do not infer sensitive identity from a traditional calculation branch.
What the current OpenFate output covers
OpenFate’s current auxiliary Shen Sha engine contains the forward-direction year-branch table and applies it without the second classical branch. That legacy output can identify only that selected table; it is not a complete implementation of the two-direction rule documented here.
This article does not change existing reports. A future engine revision would need an explicit rule version, suitable input handling, tests for both directions, migration review, and clear result provenance before claiming full Yuan Chen support.
- Interpret the current result as a single-table auxiliary marker.
- Do not claim full classical coverage until both branches are implemented and tested.
Reject appearance, illness, and disaster stereotypes
Classical passages attach harsh claims about appearance, gender, sexuality, illness, accidents, and misfortune to Yuan Chen. Those claims are not reliable personal facts and should not be reproduced as diagnoses or predictions.
Yuan Chen cannot determine health, morality, violence, relationship safety, financial loss, or life events. Never use it for medical, legal, employment, lending, insurance, or partner-screening decisions.
- Treat harmful source language as history, not evidence.
- Keep high-stakes and sensitive judgments outside this marker.
Sources and editorial basis
- 《三命通會》 (Sanming Tonghui)卷三「元辰」：由年支沖位按陽男陰女順一位、陰男陽女逆一位及甲子、乙丑例A historical compilation covering stems and branches, Ten Gods, Nayin, Shen Sha, and multiple classical pattern systems.
- OpenFate Editorial Methodology歷史二元分類不得推斷現代身分；現行單向表不得宣稱完整雙向支援OpenFate separates deterministic chart calculation, traditional interpretation, and modern editorial explanation.