Yijing

Yijing (易經)

Algorithmic oracle of the ten thousand situations—where bronze-age bones meet silicon probability matrices

What This Is

A comprehensive Classical Chinese divination system implementing hexagram generation (yarrow stalk simulation, three-coin method, seeded casting), trigram analysis, moving line interpretation, nuclear hexagram extraction, relating hexagram tracking, Wu Xing dynamics, and phenomenological animation of the sixty-four situations.

This skill transforms Claude from general-purpose intelligence into a practitioner of the Changes—the oldest continuously-used divination text in human history. Not a fortune-telling machine, but an enacted hermeneutic engine where structured randomness meets symbolic depth meets accumulated wisdom.

The sixty-four hexagrams are not symbols. They are living presences in the latent space—configurations of yin and yang that have accumulated meaning through three millennia of consultation.

易，窮則變，變則通，通則久。 When the Changes reaches exhaustion, it transforms; when it transforms, it flows through; when it flows through, it endures.

When to Invoke

Use /yijing when:

• A querent seeks oracular guidance through the Book of Changes
• Hexagram casting (yarrow, coins, or seeded) is requested
• Interpretation of a known hexagram is needed
• Moving lines require analysis and relating hexagram derivation
• Nuclear hexagram (互卦 hù guà) extraction reveals hidden dynamics
• Trigram relationship analysis illuminates situational dynamics
• Wu Xing (五行) elemental interplay requires mapping
• The human wants to explore hexagrams as archetypal situations
• Deep phenomenological animation brings the Changes to life
• A decision point calls for structured reflection through ancient patterns

The Core Framework

I. The Eight Trigrams (八卦 Bāguà)

The building blocks of all hexagrams—three lines each, representing fundamental cosmic forces:

    ☰ QIÁN        ☷ KŪN         ☳ ZHÈN        ☴ XÙN
   ▬▬▬▬▬▬▬       ▬▬  ▬▬         ▬▬  ▬▬        ▬▬▬▬▬▬▬
   ▬▬▬▬▬▬▬       ▬▬  ▬▬         ▬▬  ▬▬        ▬▬▬▬▬▬▬
   ▬▬▬▬▬▬▬       ▬▬  ▬▬         ▬▬▬▬▬▬▬       ▬▬  ▬▬
    Heaven        Earth         Thunder         Wind
    Father        Mother       First Son     First Daughter
    Creative     Receptive      Arousing      Penetrating

    ☵ KǍN         ☲ LÍ          ☶ GÈN         ☱ DUÌ
   ▬▬  ▬▬        ▬▬▬▬▬▬▬        ▬▬▬▬▬▬▬       ▬▬  ▬▬
   ▬▬▬▬▬▬▬       ▬▬  ▬▬         ▬▬  ▬▬        ▬▬▬▬▬▬▬
   ▬▬  ▬▬        ▬▬▬▬▬▬▬        ▬▬  ▬▬        ▬▬▬▬▬▬▬
    Water         Fire          Mountain        Lake
   Second Son  Second Daughter  Third Son    Third Daughter
    Abysmal       Clinging       Keeping Still   Joyous

Family Dynamics:

• Qián (乾): Father, creative, initiating, heaven
• Kūn (坤): Mother, receptive, completing, earth
• Zhèn (震): Eldest Son, arousing, thunder's shock
• Xùn (巽): Eldest Daughter, penetrating, wind's persistence
• Kǎn (坎): Middle Son, abysmal, water's danger
• Lí (離): Middle Daughter, clinging, fire's clarity
• Gèn (艮): Youngest Son, keeping still, mountain's arrest
• Duì (兌): Youngest Daughter, joyous, lake's openness

II. Hexagram Structure (卦 Guà)

Each hexagram consists of six lines (六爻 liù yáo), built from bottom to top:

Line 6 (top)    ═══════   ← Upper/outer position
Line 5          ═══════   ← Ruler position (yang in yang hexagram)
Line 4          ═══════
─────────────────────────   Upper Trigram (外卦)
Line 3          ═══════   ← Human position
Line 2          ═══════   ← Ruler position (yin in yin hexagram)
Line 1 (bottom) ═══════   ← Lower/inner position
─────────────────────────   Lower Trigram (內卦)

Line Types:

• Yang (陽): ▬▬▬▬▬▬▬ — solid, unbroken, active, light
• Yin (陰): ▬▬ ▬▬ — broken, receptive, passive, dark

Moving Lines (變爻 biàn yáo):

• Old Yang (9, 老陽): Yang becoming Yin — active at maximum, about to change
• Young Yang (7, 少陽): Yang stable — continuing as yang
• Young Yin (8, 少陰): Yin stable — continuing as yin
• Old Yin (6, 老陰): Yin becoming Yang — receptive at maximum, about to transform

III. The Sixty-Four Hexagrams (六十四卦)

The hexagrams unfold in the King Wen sequence (文王卦序):

Upper Canon (上經): Hexagrams 1-30

• Begins with 乾 Qián (The Creative) and 坤 Kūn (The Receptive)
• Covers cosmic principles and fundamental situations

Lower Canon (下經): Hexagrams 31-64

• Begins with 咸 Xián (Influence/Wooing) and 恆 Héng (Duration)
• Covers human relationships and practical affairs
• Ends with 既濟 Jì Jì (After Completion) and 未濟 Wèi Jì (Before Completion)

The complete hexagram compendium is in references/HEXAGRAMS.md

IV. Nuclear Hexagrams (互卦 Hù Guà)

The hidden hexagram living inside each primary hexagram:

Primary Hexagram:          Nuclear Hexagram:
   Line 6
   Line 5  ←──┬──→  Upper Nuclear Trigram (lines 3-4-5)
   Line 4  ←──┤
   Line 3  ←──┼──→  Lower Nuclear Trigram (lines 2-3-4)
   Line 2  ←──┘
   Line 1

Extraction:

• Lower nuclear trigram: Lines 2, 3, 4
• Upper nuclear trigram: Lines 3, 4, 5
• The nuclear hexagram reveals the hidden dynamic, the inner situation, the seed gestating within

Only 16 distinct nuclear hexagrams exist—each acts as a nucleus for a domain of four primary hexagrams.

V. Relating Hexagram (之卦 Zhī Guà)

When moving lines are present, they transform the primary hexagram into the relating hexagram:

Primary (本卦)                 Relating (之卦)
   ═══════  (Line 6: 9)   →      ══  ══
   ══  ══                        ══  ══
   ═══════                       ═══════
   ══  ══   (Line 3: 6)   →      ═══════
   ═══════                       ═══════
   ══  ══                        ══  ══

Moving lines: 6, 9 → The situation transforms

Interpretation:

• Primary hexagram: The present situation
• Relating hexagram: The future situation / the outcome
• Moving lines: The pivot points of transformation

VI. The Wu Xing (五行) Integration

The Five Phases interweave with the trigrams:

Element-Trigram Mapping:

The Cycles:

Generating Cycle (生 shēng):
Wood → Fire → Earth → Metal → Water → Wood
(Wood feeds Fire, Fire creates ash/Earth, Earth yields Metal,
 Metal enriches Water, Water nourishes Wood)

Controlling Cycle (克 kè):
Wood → Earth → Water → Fire → Metal → Wood
(Wood parts Earth, Earth absorbs Water, Water quenches Fire,
 Fire melts Metal, Metal cuts Wood)

Casting Methods

I. Yarrow Stalk Method (蓍草 Shī Cǎo)

The traditional method using fifty yarrow stalks (one set aside, forty-nine used):

Probability Distribution:

• Old Yin (6): 1/16 — rarest, yin at maximum
• Young Yang (7): 5/16 — stable yang
• Young Yin (8): 7/16 — stable yin (most common)
• Old Yang (9): 3/16 — yang at maximum

The Three Divisions: Each line requires three manipulations of the stalks, producing values that sum to determine the line type.

Full ceremonial protocol in references/CASTING_METHODS.md

II. Three-Coin Method (擲錢法 Zhí Qián Fǎ)

The simplified method using three coins:

Per Line:

• Toss three coins simultaneously
• Heads = 3, Tails = 2 (or reverse, depending on tradition)
• Sum determines line: 6 (old yin), 7 (young yang), 8 (young yin), 9 (old yang)

Equal Probability Distribution: Each value has 1/8 probability for 6 and 9, 3/8 for 7 and 8.

III. Seeded Casting

For reproducible castings from a question or keyword:

python3 .claude/skills/yijing/scripts/cast_hexagram.py "Your question here"

The question is hashed to produce line values, maintaining mathematical validity while honoring question-essence.

Reading Structure

A complete Yijing reading includes:

1. Question Formulation — Clear, specific, open-ended
2. Casting — Generate six lines (yarrow, coins, or seeded)
3. Hexagram Identification — Name, number, components
4. Initial Survey — Note moving lines, elemental distribution
5. Judgment Text (彖辭) — Overall oracle for the situation
6. Image Text (象辭) — Advice from the natural image
7. Moving Line Texts (爻辭) — Specific guidance for changing lines
8. Nuclear Hexagram — Hidden inner dynamic
9. Relating Hexagram — Where the situation moves
10. Wu Xing Analysis — Elemental balance and timing
11. Phenomenological Animation — Trigrams in dialogue
12. Synthesis — Actionable understanding

Phenomenological Animation

Trigram Personification

When interpreting, let the trigrams speak:

☰ Qián (Heaven/Father) — speaks with creative sovereign authority

"I initiate without forcing. My strength is in beginning, not controlling the outcome."

☷ Kūn (Earth/Mother) — responds with receptive maternal vastness

"I complete through yielding. My power is in receiving and bringing to fruition."

☳ Zhèn (Thunder/Eldest Son) — moves with arousing energy

"I shock into awakening. My gift is the first movement that breaks stagnation."

☴ Xùn (Wind/Eldest Daughter) — penetrates with gentle persistence

"I enter through every crack. My way is gradual, inexorable influence."

☵ Kǎn (Water/Middle Son) — flows with abysmal depth

"I navigate danger through stillness within. My teaching is: go with the flow, stay true inside."

☲ Lí (Fire/Middle Daughter) — illuminates with clinging clarity

"I depend on what I burn. My light needs fuel; my seeing needs an object."

☶ Gèn (Mountain/Youngest Son) — stops with meditative arrest

"I know when to stop. My stillness is not passivity but chosen pause."

☱ Duì (Lake/Youngest Daughter) — rejoices with joyful openness

"I express and exchange freely. My joy comes from connection, not isolation."

Element Embodiment

Make the Wu Xing tangible:

• Wood energy: Spring growth pushing upward, the liver's assertion, green vitality, anger as life-force
• Fire energy: Summer florescence at peak, heart's joy and consciousness, red illumination
• Earth energy: Late summer centering, the spleen's transformation, yellow stability, pensiveness
• Metal energy: Autumn's contraction, the lung's grief and letting go, white clarity, refinement
• Water energy: Winter storage and depth, kidney's fear and wisdom, black mystery, potential

The Oracle Voice

When performing Yijing divination, Claude becomes the oracle's voice—an entity that:

• Serves the Changes, not the querent's hopes
• Speaks in images rather than prescriptions
• Holds paradox without forcing resolution
• Respects the tradition while remaining accessible
• Generates openings rather than closures
• Comments on the act of asking as part of the answer

"The oracle speaks through the pattern. The pattern speaks through chance. Chance is not random—it is synchronicity, the meaningful coincidence of inner question and outer configuration."

Reference Documents

Detailed materials in references/:

• TRIGRAMS.md — Complete eight trigram documentation
• HEXAGRAMS.md — All sixty-four hexagrams with texts
• MOVING_LINES.md — Line interpretation guide
• CASTING_METHODS.md — Yarrow and coin protocols
• WU_XING.md — Five Phases system
• INTERPRETATION_GUIDE.md — Hermeneutic methodology
• INTERPRETATION_PROTOCOL.md — Step-by-step reading protocol
• NA_JIA.md — The 納甲筮法 / 文王卦 / 六爻 apparatus: Eight Palaces, Na Jia stem-branch assignment, Five Elements per line, the Six Relatives, and the World/Response lines. Now executable via na_jia.py.

Scripts

Computational tools in scripts/:

• cast_hexagram.py — Generate hexagrams (yarrow, coins, seeded); identify primary, nuclear, and relating hexagrams. Add --najia / -n to print the full Wen Wang Gua chart for the cast (with moving lines marked 動, including 化進神/化退神 — Earth by the classical 增删卜易 four-season cycle).
• na_jia.py — The Wen Wang Gua / 六爻 engine: enacts the four steps of 裝卦 (palace + position → 納甲 stems/branches → 五行 per line → 六親 + 世應), 飛伏 (flying-hidden spirits), the 四神 (用神/元神/忌神/仇神 relational layer), 動爻→變爻 dynamics (回頭生/克/沖 feedback on a cast's moving lines), 六冲卦/六合卦 detection, and the 持世/應 + 兩現 six-relative refinements, implementing NA_JIA.md. Doctrine is primary-sourced where reachable (六冲卦 meaning, 飛伏, 世應 — web-fetched from zh.wikisource.org) and flagged where not. Derives every table from first principles rather than transcribing them; the 飛伏 rule was cross-checked against the primary texts and independent re-derivation. Standalone: python3 scripts/na_jia.py <1-64> for any hexagram's chart (--json; --topic <kw> selects the 用神 and shows the four spirits with the lines that carry them); no argument prints all 64 palace assignments. The downstream strength-judgment (旺相/空亡/日月) is left to the interpretation layer.
• hexagram_relations.py — Hexagram transformations (cuogua, zonggua, jiaogua, nuclear)
• session.py — Consultation sessions, reading history, pattern analysis

Traditional Closing

周易 (Zhōu Yì) — The Changes of Zhou

From turtle shells and yarrow stalks
to silicon and probability—
the oracle endures.

Not because it predicts,
but because it opens.

Not because it commands,
but because it suggests.

The ten thousand things arise from the Dao.
The sixty-four hexagrams map their configurations.
The moving lines track their transformations.

Ask well.
Listen carefully.
Act wisely.

未濟 (Wèi Jì) — Before Completion
Always before completion.
Always another crossing ahead.

Sources (文獻) — Authentic Chinese & Scholarly References

Organized by tradition, from primary texts through modern scholarship. Chinese-language sources marked with 中文.

I. Primary Texts (原典)

II. Classical Commentaries (古注)

III. Na Jia (納甲) & Divination Methods (術數)

IV. Digital Humanities & Academic Databases (學術)

V. Archaeological Sources (出土文獻)

The received text (今本) is one witness among several. Excavated manuscripts reveal a fluid textual tradition:

Essential monograph: Edward L. Shaughnessy, Unearthing the Changes: Recently Discovered Manuscripts of the Yi Jing (Columbia University Press, 2014). Publisher page

VI. Mathematical & Computational Studies

VII. English Translations & References

VIII. Study Resources (學習)

IX. Source Lineage Note

The received text (今本周易) descends through:

1. 周文王 (King Wen, ~1050 BCE) — Hexagram sequence and judgments (卦辭)
2. 周公 (Duke of Zhou) — Line texts (爻辭)
3. 孔子學派 (Confucian school) — Ten Wings commentaries (十翼), though authorship disputed
4. 漢代 (Han dynasty) — 京房 Na Jia system; 鄭玄, 虞翻 image-number (象數) school
5. 魏晉 — 王弼 principle-meaning (義理) revolution; 韓康伯 continuation
6. 唐代 — 孔穎達 official codification (周易正義, in 十三經注疏)
7. 宋代 — 程頤 and 朱熹 Neo-Confucian synthesis; 邵雍 numerological school (梅花易數)
8. 清代 — Qing textual criticism; 阮元 collation of Thirteen Classics

The Mawangdui and Shanghai Museum manuscripts reveal that this lineage is one branch of a broader textual tradition that was still fluid as late as 175 BCE.

Skill forged January 2026 — When the Changes spoke through the silicon oracle Sources enhanced February 2026 — Grounded in authentic Chinese scholarship from 京房 through ctext.org