Pattern Selection in BaZi — From 《子平真诠》 to the Deep Oracle Engine

Pattern is the BaZi chart's skeleton, not its decoration

If BaZi reading stops at day master + ten gods, you lose the chart's overall "shape" — the structural difference that makes one Geng-metal day master fundamentally distinct from another Geng-metal day master. Pattern (格局, 格) is that shape.

《子平真诠》 opens by stating: "Among the eight characters, only Wealth, Officer, Resource, Output, and Hurting Officer are taken as patterns." Pattern selection is fundamentally about: finding within the month branch (where the chart's force is concentrated) the ten god that best represents the chart's structural character, and using it to name the entire structure.

This article walks through the Ziping school's standard procedure — also the actual flow inside Deep Oracle's in-depth BaZi reading pattern engine.

Step 1: Decompose month-branch hidden stems

Earthly branches aren't single units — each branch internally "hides" one to three heavenly stems. For example, Wu (午) hides Ding-fire (primary) and Ji-earth (secondary); Shen (申) hides Geng-metal (primary), Ren-water (secondary), and Wu-earth (residual).

The traditional 《子平真诠》 mapping for each month branch:

- Zi (Nov-Dec): Gui (primary 100%) - Chou (Dec-Jan): Ji primary, Gui secondary, Xin residual - Yin (Jan-Feb): Jia primary, Bing secondary, Wu residual - Mao (Feb-Mar): Yi (primary 100%) - Chen (Mar-Apr): Wu primary, Yi secondary, Gui residual - Si (Apr-May): Bing primary, Wu secondary, Geng residual - Wu (May-Jun): Ding primary, Ji secondary - Wei (Jun-Jul): Ji primary, Ding secondary, Yi residual - Shen (Jul-Aug): Geng primary, Ren secondary, Wu residual - You (Aug-Sep): Xin (primary 100%) - Xu (Sep-Oct): Wu primary, Xin secondary, Ding residual - Hai (Oct-Nov): Ren primary, Jia secondary

Step 2: Primary stem transparent → take as pattern

Core rule: if the month branch's primary hidden stem is transparent in any of the year/month/hour stems, the ten god corresponding to that stem becomes the pattern.

Example: Bing-fire day master, month branch Shen. Shen's primary is Geng-metal (Geng to Bing is Indirect Wealth). If Geng appears in the year, month, or hour stem positions, the chart takes the Indirect Wealth Pattern. If Geng is not transparent but Ren (secondary) is, the chart may take the Seven Killings Pattern instead (Ren to Bing is Seven Killings).

Deep Oracle's pattern engine searches in this priority order: 1. Is the primary transparent? Yes → take primary's pattern. 2. Primary not transparent, but secondary is → take secondary's pattern. 3. Secondary also not transparent → take residual. 4. None of the three transparent → enter the special-pattern identification flow (see below).

The free BaZi chart calculator output already includes month-branch hidden-stem analysis, so primary/secondary/residual transparency is directly visible.

Step 3: The eight standard patterns

Classified by the ten-god relationship between the month-branch's representative element and the day master:

- Direct Officer Pattern (正官格): month branch yields Direct Officer (controls me, opposite polarity). - Seven Killings Pattern (七杀格): month branch yields Seven Killings (controls me, same polarity). - Direct Resource Pattern (正印格): month branch yields Direct Resource (generates me, opposite polarity). - Indirect Resource Pattern (偏印格): month branch yields Indirect Resource (generates me, same polarity). - Direct Wealth Pattern (正财格): month branch yields Direct Wealth. - Indirect Wealth Pattern (偏财格): month branch yields Indirect Wealth. - Eating God Pattern (食神格): month branch yields Output, same polarity. - Hurting Officer Pattern (伤官格): month branch yields Output, opposite polarity.

Note: Friend (比肩) and Rob Wealth (劫财) — the day master's own party — generally do NOT establish a pattern, because the day master's own kind cannot characterize the chart's overall structure.

Step 4: Special patterns (外格) — the boundary

When none of primary/secondary/residual is transparent, or when the chart's overall force structure clearly diverges from standard-pattern logic, the special-pattern identification process triggers. Common special patterns:

Single-Element Dominant (一行独旺): covered in detail in the four useful-god selection schools. Includes Curving Straight (Wood dominant), Blazing Upward (Fire), Flourishing Earth, Transformative Metal, Flowing Down (Water).

Following Patterns (从格): day master has zero root in the month branch, all force concentrated in one ten-god group, day master can only "follow." Includes Following Wealth, Following Officer, Following Killings, Following Output (从儿), and Following General Force (从势).

Transformation Patterns (化格): day master combines with an adjacent year-pillar or month-pillar stem (the five classical combinations: Jia-Ji → Earth, Yi-Geng → Metal, Bing-Xin → Water, Ding-Ren → Wood, Wu-Gui → Fire) and the month branch supports the transformed element — the entire chart is then read by the transformed element.

Two-Element-Image Pattern: only two elements are present in the chart, in either generative or controlling sequence.

Special-pattern entry threshold is high — about 80% of real charts fall within the standard-pattern range. Deep Oracle's engine triggers higher confidence thresholds when entering the special-pattern channel.

Step 5: Pattern success vs failure

Identifying the pattern isn't enough — also judge whether it succeeds (格成) or fails (格败):

- Pattern succeeds: supporting stars (相神, the characters that activate the useful god) are present, taboo gods are controlled, the useful god has force. Example: Direct Officer Pattern with Resource present to protect Officer, Wealth present to generate Officer, taboos (Hurting Officer, Seven Killings) controlled — pattern succeeds. - Pattern fails: supporting stars missing, taboo gods unchecked, useful god clashed. Example: Direct Officer Pattern with Hurting Officer rampant attacking Officer, Resource absent, Officer clashed — pattern fails.

Pattern success allows noble qi to flow; pattern failure means structural turbulence in the life arc. But "success" doesn't mean smooth sailing, and "failure" doesn't mean nothing-to-work-with — these are structural-layer reads. Real outcomes still depend on luck pillars and annual transits.

Where Deep Oracle's pattern engine has boundaries

Pattern selection can be heavily automated, but two cases need human or LLM judgment:

1. Standard vs special pattern boundary: when one element approaches the ~50% threshold, whether single-element-dominant applies has interpretive room. The engine outputs probability, not a binary verdict. 2. Multiple patterns coexisting: rare charts have multiple pattern signatures simultaneously (e.g. Direct Officer + Eating God), requiring a weighting decision on which is primary.

The in-depth reading pattern section outputs primary pattern + secondary pattern + confidence as three separate fields, avoiding false binary conclusions.

Relationship to the [BaZi schools comparison](/bazi/blog/bazi-schools-comparison)

This article uses the Ziping school's standard procedure — the most systematized pattern-selection framework in the Chinese BaZi corpus. The Blind School and Modern School handle pattern differently: Blind School relies less on "pattern" naming and works more from concrete imagistic correspondences; Modern School reframes pattern as personality archetype framework. Detailed comparison: BaZi schools comparison.

YMYL framing

Pattern selection is internal-methodology within the BaZi system. This article is a cultural interpretive framework, not a substitute for medical advice or psychological diagnosis. For health, financial, or relationship decisions with real-world consequences, please also consult licensed professionals.

Going further

- See your own chart's pattern verdict: in-depth BaZi reading. - Useful-god selection's relationship to pattern: the four useful-god decision schools. - Full Deep Oracle methodology: BaZi methodology overview. - Foundational learning: BaZi learning hub and insight library.