Dui

Definition

Pronunciation: duì

Also spelled: Tui, The Joyous, The Lake, Marsh, Open Mouth, ☱

Dui (兌) means 'to exchange,' 'to open,' or 'joy' — the trigram formed by one yin line resting above two yang lines (☱), symbolizing a lake whose open surface receives and reflects everything above while concealing depth and strength beneath.

Etymology

The character dui (兌) depicts an open mouth above a person — the act of speaking, expressing, or opening. The Shuogua Zhuan (Discussion of the Trigrams) states: 'Dui is the lake. It is the youngest daughter. It is the sorceress. It is mouth and tongue. It is smashing and breaking apart. It is dropping off and bursting open. Among soils it is hard and salty.' The mouth association is primary — Dui represents the capacity to express, communicate, persuade, and bring joy through speech. The trigram's structure reinforces this: the two strong yang lines below represent inner strength and substance, while the single yin line above represents openness, receptivity, and the capacity to receive from above. A lake is open at the surface but deep and solid below — it receives rain and light while concealing its depths.

About Dui

Dui occupies the west in the Later Heaven (Houtian) trigram arrangement, corresponding to autumn, the evening, and the metal phase in wuxing (five phases) correlation. Its season is mid-autumn, the harvest period when the year's labor produces tangible results and people gather in celebration. Its time is late afternoon into evening — the hours of relaxation, conversation, and social pleasure after the day's work.

In the family model, Dui is the youngest daughter (shao nu 少女). She is formed when a single yin line enters the father's (Qian's) three yang lines at the top position, creating softness and openness in the highest place while maintaining strength below. The youngest daughter archetype embodies charm, expressiveness, and the capacity to bring people together through the pleasure of her company. This is not frivolous: the Shuogua Zhuan associates Dui with the sorceress (wu 巫), connecting joy and speech to spiritual power. In ancient Chinese religion, the wu communicated between human and spirit worlds through ecstatic speech and dance.

The natural image of the lake encodes Dui's essential dynamic. A lake is open at the surface — it receives rain, reflects sky, and makes its contents visible. Below the surface, a lake contains depth, pressure, and hidden life. Two lakes communicating — as in Hexagram 58 (Dui doubled, The Joyous) — represent the ideal of mutual exchange: two people sharing openly, each enriched by the other's expression. Richard Wilhelm translates the Image of Hexagram 58: 'Lakes resting one on the other. The image of the Joyous. Thus the superior person joins with friends for discussion and practice.'

The joy Dui represents is not mere happiness but the specific pleasure that arises from successful communication and exchange. When people speak truthfully and are heard, when ideas circulate freely, when expression meets receptive understanding — this is Dui's joy. The Xici Zhuan states: 'Dui means pleasure. It is the one that makes all creatures happy.' But the text immediately warns: 'Dui is the trigram of autumn, the season when all things rejoice; but autumn is also the season of judgment and execution.' Joy and severity coexist in Dui because speech has consequences — the open mouth that brings pleasure can also pronounce judgment.

In the wuxing framework, Dui belongs to metal, sharing this correspondence with Qian (heaven). Where Qian's metal is the strong, initiating, unyielding force of heaven, Dui's metal is the refined, reflective, communicative aspect — metal as the medium that conducts sound, the bell that makes music, the mirror that reflects truth. In Traditional Chinese Medicine, the metal phase governs the lung and large intestine, and Dui's correspondence with the mouth, voice, and breath connects it to lung function — the organ of inspiration and expression.

Dui appears as the upper trigram in hexagrams dealing with communication, persuasion, and social dynamics. Hexagram 17 (Sui, Following) places Dui over Zhen (thunder) — joyful expression above arousing movement creates the condition where people willingly follow. Hexagram 31 (Xian, Influence/Courtship) places Dui over Gen (mountain) — the lake above the mountain is the image of attraction and mutual sensitivity, making this the hexagram of romantic influence and emotional responsiveness.

As the lower trigram, Dui represents inner joy, personal pleasure, and the foundation of expressive capacity. Hexagram 43 (Guai, Breakthrough/Resoluteness) places Qian (heaven) over Dui — creative force building on a foundation of joyful determination produces the decisive breakthrough. Hexagram 47 (Kun, Oppression/Exhaustion) places Kan (water) over Dui — water draining from the lake creates the image of resources depleted, joy suppressed, speech failing to reach its audience.

In Baguazhang martial arts, Dui corresponds to the 'enveloping palm' (bao zhang 抱掌), characterized by soft, enclosing movements that redirect force through yielding rather than opposing. The practitioner embodies Dui's principle: appear open and receptive on the surface while maintaining powerful structure beneath.

Wang Bi's commentary emphasizes Dui's role as the trigram of influence through gentleness. Where Qian commands through authority and Zhen startles through force, Dui persuades through pleasure. The Daodejing, Chapter 78, expresses a parallel principle: 'Nothing in the world is as soft and yielding as water, yet for dissolving the hard and inflexible, nothing can surpass it.' Dui's lake achieves through receptive openness what force cannot accomplish through pressure.

The doubled Dui hexagram (Hexagram 58, The Joyous) is one of eight hexagrams formed by doubling a trigram. Its Judgment states: 'The Joyous. Success. Perseverance is favorable.' The Image reads: 'Lakes resting one on the other. Thus the superior person joins with friends for discussion and practice.' Two lakes connected by underground channels sustain each other — when one overflows, the other receives; when one depletes, the other replenishes. This is the I Ching's image of healthy relationship: mutual exchange that sustains both parties through reciprocal openness.

Significance

Dui holds a distinctive position among the eight trigrams as the symbol of communication, exchange, and the pleasure that arises from genuine expression. While other trigrams represent forces (Qian's creative power, Zhen's arousal) or conditions (Kan's danger, Gen's stillness), Dui represents a relational quality — the dynamic that emerges when two or more beings exchange openly.

The association between joy and speech in Dui reflects a deep Chinese philosophical insight: that authentic expression is itself a source of happiness, and that the suppression of expression produces suffering. This principle became foundational in Chinese medical theory, where stagnation of lung qi (the metal-phase organ) produces grief, and grief produces further stagnation — a cycle broken by the expressive function that Dui represents.

Dui's dual nature — joyful openness combined with hidden depth and the capacity for judgment — prevents the trigram from being merely pleasant. The sorceress (wu) association connects joy to spiritual power; the autumn correspondence connects pleasure to the harvest's reckoning. Dui teaches that genuine communication requires both the courage to speak openly and the depth to sustain what one says.

Connections

Dui pairs with Qian (heaven) in the metal phase of the wuxing system, with Qian representing metal's initiating power and Dui its communicative and reflective aspect. In the Earlier Heaven arrangement, Dui faces Gen (mountain) across the trigram circle — open exchange opposite silent stillness.

The hexagrams containing Dui often deal with themes of influence, attraction, and persuasion: Hexagram 31 (Xian, Influence) combines Dui with Gen to produce the archetype of courtship and emotional sensitivity. Hexagram 58 doubles Dui to produce the archetype of mutual enrichment through joyful exchange.

Dui's emphasis on communication and joy through expression connects to the Sufi concept of sohbet (spiritual conversation) — the tradition that truth is transmitted through intimate, joyful dialogue between seeker and teacher. The Vishuddha (throat) chakra in the yogic system governs the same domain: authentic expression, communication, and the creative power of speech.

Frequently Asked Questions

Why is the lake associated with joy rather than sadness or depth?

The association rests on the trigram's structural image rather than Western romantic associations with lakes as melancholy places. In the I Ching, the lake's defining characteristic is its open surface — it receives freely from above (rain, light, sky) while offering its contents visibly to all who approach. This openness is the structural basis of joy in Chinese philosophy: the capacity to give and receive without obstruction. The Shuogua Zhuan identifies Dui specifically with the mouth and with speech — the lake's open surface is the open mouth that speaks, laughs, and connects. Joy in the Dui sense is not passive contentment but active exchange: the pleasure of conversation, the satisfaction of being heard, the delight of mutual understanding. The lake is joyous because it is fundamentally relational — it exists by receiving (rain, streams) and giving (reflection, sustenance, beauty). A sealed vessel cannot be joyous in the Dui sense. Only the open container, willing to receive and reflect, generates the dynamic the I Ching calls dui-joy.

What is the connection between Dui and the sorceress (wu)?

The Shuogua Zhuan's association of Dui with the wu (巫, sorceress/shaman) is one of the trigram system's most enigmatic correspondences. The wu in ancient Chinese religion were ritual specialists — predominantly but not exclusively female — who communicated between the human and spirit worlds through ecstatic speech, dance, and song. They were the original mediators, using the power of expression (Dui's core function) to bridge visible and invisible realms. The connection reveals that Dui's joy is not secular entertainment but has spiritual dimensions: authentic expression opens channels between levels of reality. The wu's ecstatic speech was understood as joyful precisely because it reconnected separated worlds — human and divine, living and dead, visible and invisible. This spiritual dimension of communication persists in Chinese culture through practices like poetic recitation, ritual chanting, and the Daoist concept of zhenyan (真言, 'true words') — speech that transforms reality because it expresses genuine truth. Dui as the trigram of the wu reminds practitioners that communication at its deepest is a sacred act.

How does Dui function differently as upper versus lower trigram?

As the upper (outer) trigram, Dui represents the external expression of joy, the social manifestation of communication, and the outer environment being characterized by openness and exchange. Hexagram 17 (Sui, Following) with Dui above Zhen (thunder) produces willing followership — the outer atmosphere of joy and receptivity makes people want to participate. Hexagram 45 (Cui, Gathering Together) with Dui above Kun (earth) creates the conditions for assembly — joyful openness in the social environment draws people together. As the lower (inner) trigram, Dui represents inner joy, personal capacity for expression, and the inner foundation of communicative power. Hexagram 43 (Guai, Breakthrough) with Qian above Dui means creative force building on inner joyful determination — the breakthrough succeeds because its foundation is genuine conviction, not forced effort. Hexagram 47 (Kun, Oppression) with Kan above Dui shows water pressing down on inner joy — the experience of being silenced, of having one's natural expressiveness suppressed by external circumstances. The position determines whether joy is expressed outward or experienced inward, and whether it flows freely or meets resistance.