In Korea, there exists a body of knowledge called saju (four pillars of destiny) that has never been formally recognized as an academic discipline, yet it quietly permeates every layer of culture and daily life. It appears in casual conversation when someone chooses an auspicious date for a wedding, a housewarming, or launching a business. At times it intertwines with shamanic traditions, at other times it is quietly absorbed into humanistic self-reflection, and quite often it simply lives on as an unspoken habit woven into ordinary existence.
I’d like to explore saju not as fortune-telling, but as a lens—through the perspective of humanities and the textures of everyday life. It might turn out to be surprisingly interesting.
To understand saju at all, one must first become acquainted with its foundational grammar: yin-yang and the five phases (음양오행).
1. What are yin-yang and the five phases?
They form the skeletal structure of Korean saju cosmology (and much of East Asian philosophy). In the simplest terms:
- Yin and yang divide the world into two complementary poles.
- The five phases (wood, fire, earth, metal, water) take those poles and arrange them into five dynamic energies that support, restrain, and ultimately balance one another.
The universe—and every human life within it—moves according to this quiet choreography of opposition and mutual dependence.
2. Yin & yang – seeing the world in pairs
Yin and yang are not enemies, nor are they merely opposites. They are dance partners who refuse to perform without each other.
| Yang qualities | Yin qualities |
|---|---|
| day, brightness, heat | night, darkness, coolness |
| activity, speed, outward | stillness, slowness, inward |
| above, front, south, summer | below, back, north, winter |
Look at the taiji (太極) symbol: the white field always contains a black seed, and the black field always hides a white seed. There is no such thing as pure yang or pure yin. Each carries the embryo of the other inside itself.
3. The five phases – the world seen through five colors
Everything in heaven and earth is classified into five elemental movements:
| Phase | Core image | Color | Season | Direction | Organ |
|---|---|---|---|---|---|
| Wood (木) | tree, growth, sprouting | azure | spring | east | liver |
| Fire (火) | flame, passion, illumination | red | summer | south | heart |
| Earth (土) | soil, centering, stability | yellow | late summer | center | spleen |
| Metal (金) | ore, harvest, contraction | white | autumn | west | lungs |
| Water (水) | flow, wisdom, depth | black | winter | north | kidneys |
4. The relationships: mutual generation & mutual restraint
The five phases are never static. They live in constant conversation.
Mutual generation (相生) – the nurturing cycle Wood feeds Fire → Fire creates Earth (ash) → Earth bears Metal → Metal condenses Water → Water nourishes Wood.
Mutual restraint (相剋) – the controlling cycle Wood penetrates Earth → Earth dams Water → Water extinguishes Fire → Fire melts Metal → Metal cuts Wood.
It is this elegant tension—giving and limiting—that keeps the world from tipping into chaos or stagnation.
5. How yin-yang and the five phases appear in actual saju
Your birth year, month, day, and hour are converted into eight characters (four heavenly stems + four earthly branches). Each character carries its own yin/yang polarity and five-phase affiliation.
Example: the day pillar 甲子 (Gap-Ja) → 甲 = yang wood → 子 = yang water → This person carries a strong yang-wood energy supported by yang-water.
By mapping the distribution of these energies across the eight characters, a saju reader can discern tendencies in temperament, health vulnerabilities, relational patterns, and even the larger rhythm of one’s life.
Closing thought
Yin-yang and the five phases are not scientific laws in the modern sense. Yet they are far from mere superstition. They represent thousands of years of accumulated human pattern recognition—a quiet, patient attempt to map how character, timing, environment, and relationship interact.
Think of yin-yang as the principle of balance, and the five phases as a pair of philosophical spectacles that tint the world in five shades.
Once you wear those spectacles, even ordinary moments begin to look strangely coherent.
(If you’re curious, leave your birth date—solar or lunar—and I’ll give you a quick five-phase snapshot in the comments. Who knows what color your life is leaning toward these days?)