The Eight Trigrams
The Eight Trigrams (Bagua) are the fundamental structural units of the I Ching, each composed of three Yin or Yang lines representing the eight primordial forces of nature: Heaven, Earth, Thunder, Water, Mountain, Wind, Fire, and Lake.
What is The Eight Trigrams?
The Eight Trigrams (Bagua) are eight three-line symbols attributed in tradition to the legendary emperor Fu Xi through observation of nature. Each trigram consists of three lines (Yao) stacked from bottom to top, where each line is either Yang (⚊, solid) or Yin (⚋, broken). This gives 2³ = 8 possible permutations: ☰ Qián (Heaven), ☷ Kūn (Earth), ☳ Zhèn (Thunder), ☵ Kǎn (Water), ☶ Gèn (Mountain), ☴ Xùn (Wind), ☲ Lí (Fire), ☱ Duì (Lake). Each trigram has a traditional "virtue" (卦德) — Qián is Strong, Kūn is Yielding, Zhèn is Arousing, Kǎn is Abysmal — used as one interpretive layer for the 64 hexagrams.
Interpretation & Usage
In practical divination, the "Myriad Image Correspondence" (万物类象) of the Eight Trigrams is a common technique. Each trigram maps not only to a natural force but also to body parts, family roles, animals, Five Element affinities, and compass directions. For example: if you cast a hexagram with Lí (Fire/Eyes/Middle Daughter) above and Kǎn (Water/Ears/Middle Son) below, it might describe a relationship of "inner turmoil beneath a brilliant surface," or involve a romantic dynamic between middle-aged partners. The trigram correspondence system helps break a complex hexagram into an upper-lower trigram interaction, which still needs to be checked against changing lines, focus lines, and timing conditions.
Frequently Asked Questions
Q.What is the relationship between trigrams and hexagrams?
Trigrams have 3 lines; hexagrams have 6 lines. Each of the 64 hexagrams is formed by stacking two trigrams: the bottom one is called the "Inner" or "Lower" trigram, the top one the "Outer" or "Upper" trigram. 8 × 8 = 64 possible combinations.
Q.What is the difference between Earlier and Later Heaven Bagua?
The Earlier Heaven (Fu Xi) Bagua depicts the ideal abstract cosmic order using symmetry and opposition. The Later Heaven (King Wen) Bagua maps trigrams to real-world compass directions and seasonal cycles, which is the version used in Feng Shui practice.
See It in Context
Want to see where The Eight Trigrams appears in context? Open a chart or casting result, then read it alongside this term guide.
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