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BaZi / Four Pillars / Saju

Computed variants
Personal wiki reading

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How to use the Four Pillars explorer

Inspect pillars, visible and hidden stem meanings, and the six-combination/six-clash relationships between actual branch positions under your chosen clock convention.

Inputs: A birth profile with exact local time, location and IANA timezone; a clock convention and day boundary.

  1. Choose the clock convention used by the method you want to study.
  2. Select a year, month, day or hour pillar; read its calculated label and attributed interpretation.
  3. Open Branch relationships, select one of the six positional pairs, and read its sourced match or no-match result. Adjacency is recorded without a strength score.
  4. Compare the six rows to see which pillars differ when the clock or day boundary changes.
  5. Inspect the cycle date and hour-stem convention before downloading the result.
Teaching example · invented coordinates

Teaching example: at civil 2024-01-01 23:00, the midnight convention gives day Jia-Zi and hour Jia-Zi; the 23:00 convention gives day Yi-Chou and hour Bing-Zi. Here, the hour stem always follows the selected cycle-day stem.

Introductory pillar inspection only. Visible and hidden-stem Ten Gods and main qi are included, together with six-combination/six-clash pair membership. Pair transformations, precedence and other branch patterns need separate rules. Seasonal weights, strength, favorable elements and luck periods require additional named methods. A midnight-day school that advances the late-Zi hour stem uses a different rule.

Open the Four Pillars explorer →All glossary terms →
Sources and conventions

History & development

Four Pillars arranges the year, month, day and double-hour into stem–branch pairs. The older calendrical cycles precede their combination as Eight Characters. The Hong Kong Observatory documents the cycle and the relations used to derive month and hour stems. Saju is the Korean name commonly applied to the Four Pillars tradition.

Mythology & symbolic world

Ten stems and twelve branches carry yin–yang, five-phase and animal correspondences. The animals are symbolic names for branch positions; a Pig year is not a claim about the physical constellation occupied by a planet.

Provenance: where the rules come from

The engine uses the birth instant for solar-term year and month, then reports civil, local-mean-solar and apparent-solar hour variants with explicit day-turnover choices.

How it is calculated

Solar-term year/month plus sexagenary day/hour.

Choices that change the result: Civil, local mean and apparent-solar variants; day starts at midnight or23:00; luck cycles deferred.

Inspect your calculated data →

Uses & use cases

  • Learn what the eight characters actually encode.
  • Compare regional clock conventions before attempting a traditional reading.

Interpretation methods

Method 1

Establish the chart before interpretation

Compute the four pairs, identify the day stem, and only then examine the school’s phase relations and seasonal rules.

Study example

For a sample birth near an hour boundary, civil, mean solar, and apparent solar time may assign different hour pillars. Compare the three results while keeping the birth instant fixed.

Explore these reading approaches

Comparison across systems ↗

Concepts in this tradition

Follow a term for its definition, word origin, evidence and connected ideas.

BaZi / Four Pillars / Saju →Six combinations →Six clashes →Three harmonies →Seasonal meetings →

Disagreements & limits

  • The birthday’s ten-minute proximity to an hour boundary makes the clock convention material.
  • Luck direction and start-age methods require additional choices.
  • The cycle labels are computable; judgements about temperament or destiny require separate evidence.

Sources & evidence

Practitioner sources describe their own systems. Historical and astronomical sources support different kinds of claims. Reading exercises are editorial teaching examples.

  1. Heavenly Stems and Earthly Branches — Hong Kong Observatory ↗government calendrical explanation
  2. The 24 Solar Terms — Hong Kong Observatory ↗government astronomical explanation
  3. Facts about Korea — Korean Culture and Information Service ↗government cultural reference
  4. Wang and Zhang (2020) · traditional five-phase cycle order ↗

Connected entries

Chinese lunisolar zodiac →Zi Wei Dou Shu / Tử Vi →Qi Men Dun Jia / Da Liu Ren / Tai Yi →Nine Star Ki / Kyūsei →