The Eight Trigrams
Universe's Eight Basic Symbols · 八卦——宇宙的八種基本符號
If yin and yang are the alphabet, then the Eight Trigrams (八卦, Bāguà) are the first words. By stacking three yin or yang lines, ancient sages created eight fundamental symbols — each representing a primal force of nature. Together, they form a complete vocabulary for describing the universe.
How the Trigrams Are Formed
A trigram (卦, guà) is built by stacking three lines (爻, yáo), each of which is either yang (—) or yin (- -). Since each position has two possibilities and there are three positions, we get 2³ = 8 combinations — the Eight Trigrams.
Each line represents a level of reality, embodying the ancient concept of the Three Talents (三才, Sāncái):
Every trigram simultaneously speaks to heaven, humanity, and earth — the three dimensions of any situation.
Meet the Eight Trigrams
乾 Qián
- Direction: Northwest
- Family: Father
- Element: Metal
- Animal: Horse
- Body: Head
震 Zhèn
- Direction: East
- Family: Eldest Son
- Element: Wood
- Animal: Dragon
- Body: Feet
巽 Xùn
- Direction: Southeast
- Family: Eldest Daughter
- Element: Wood
- Animal: Rooster
- Body: Thighs
坎 Kǎn
- Direction: North
- Family: Middle Son
- Element: Water
- Animal: Pig
- Body: Ears
離 Lí
- Direction: South
- Family: Middle Daughter
- Element: Fire
- Animal: Pheasant
- Body: Eyes
艮 Gèn
- Direction: Northeast
- Family: Youngest Son
- Element: Earth
- Animal: Dog
- Body: Hands
兌 Duì
- Direction: West
- Family: Youngest Daughter
- Element: Metal
- Animal: Sheep
- Body: Mouth
The Memory Rhyme
For centuries, students have memorized the trigrams using a famous mnemonic verse attributed to the Song Dynasty scholar Zhu Xi (朱熹). It describes the visual shape of each trigram:
💡 Study Tip: Look at each trigram's Unicode symbol above and match it to the description. For example, ☲ (Lí/Fire) has solid lines on top and bottom but is "empty in the middle" — the middle line is broken. Once you see the visual pattern, you'll never forget it.
Two Arrangements: Earlier & Later Heaven
The eight trigrams can be arranged in two fundamentally different patterns, each revealing a different aspect of reality:
先天八卦 — Earlier Heaven
Fuxi's arrangement (reconstructed by Song Dynasty scholar Shao Yong)
Depicts the ideal, cosmic order — how the universe is structured in its primordial state. Trigrams are placed as opposing pairs:
- ☰ Heaven (South) ↔ ☷ Earth (North)
- ☲ Fire (East) ↔ ☵ Water (West)
- ☳ Thunder (NE) ↔ ☴ Wind (SW)
- ☶ Mountain (NW) ↔ ☱ Lake (SE)
Principle: Complementary opposition. Each pair balances the other perfectly.
後天八卦 — Later Heaven
King Wen's arrangement
Depicts the dynamic, temporal order — how energy actually flows through the seasons and compass directions:
- ☲ Fire → South (summer, noon)
- ☵ Water → North (winter, midnight)
- ☳ Thunder → East (spring, dawn)
- ☱ Lake → West (autumn, dusk)
Principle: Sequential flow. Energy circulates through phases of growth and decline.
"先天者，體也；後天者，用也。"
— Traditional saying
"Earlier Heaven is the structure (體); Later Heaven is the function (用)."
In divination, the Earlier Heaven sequence provides the numerical encoding (Qian=1, Dui=2, Li=3...), while the Later Heaven governs directional and seasonal analysis. Both are essential tools.