BAZI KNOWLEDGE BASE
What Is Water Under the Stream (澗下水) in BaZi?
Water Under the Stream is the water-class Nayin (a separate named element classification for a complete pair of chart symbols) assigned to 丙子 and 丁丑. San Ming Tong Hui pictures clear water among mountains and favors particular metals while distinguishing soil, fire, and other waters by exact pair; historical moral, sexual, poverty, and harm claims are not modern facts.
What does Water Under the Stream establish first?
Water Under the Stream is the Nayin name for a complete 丙子 or 丁丑 pillar, and its Nayin phase is Water. It may occur in the Year, Month, Day or Hour Pillar (the two-symbol column for the birth hour). The lookup unit is always one stem–branch pair in the same pillar, never a single character or a cross-pillar combination.
This lookup establishes one historical classification. 丙 remains a Fire stem and 子 a Water branch; 丁 remains a Fire stem and 丑 a Earth branch. Nayin Water does not overwrite those ordinary Five-Phase facts.
How can you check for Water Under the Stream?
Read each complete pillar in an already calculated chart. A pillar that is exactly 丙子 or 丁丑 has the Water Under the Stream Nayin. One matching character, a zodiac animal or a real-world object is insufficient.
| Complete Jiazi | Stem phase | Branch phase | Nayin name | Nayin phase |
|---|---|---|---|---|
| 丙子 | Fire | Water | Water Under the Stream | Water |
| 丁丑 | Fire | Earth | Water Under the Stream | Water |
Worked example: how should a 丙子 Year Pillar be recorded?
Suppose the Year Pillar (the two-symbol column for the birth year) is 丙子. The table returns Water Under the Stream. A clear record says: Year 丙子; stem 丙 is Fire, branch 子 is Water; Nayin is Water Under the Stream, classed as Water. This keeps the Nayin field separate from ordinary elemental data.
If 丁 appears only in the Month Pillar (the two-symbol column for the birth month) and 丑 only in the Day Pillar (the two-symbol column for the birth day), they do not form the same-pillar 丁丑 combination and do not create Water Under the Stream. Complete pairing comes before image interpretation.
Why does the source use the name Water Under the Stream?
San Ming Tong Hui describes fine, clear water moving through a mountain setting and favors selected Sand Gold and Sword Edge Gold support. It separately evaluates Hairpin Gold, particular stem combinations, and the risk of clashes rather than treating every metal as identical nourishment. Wood, earth, fire, and other waters are also divided by amount, position, and exact Nayin pair. The source includes social, sexual, financial, and harm judgments typical of its period; responsible modern editing retains the structural conditions but rejects those claims as facts about a reader. Identify the exact supporting metal or conflicting pair. Separate usable structural rules from historical moral judgments.
What value does Water Under the Stream offer a modern reader?
Its practical value is precise lookup: 丙子 and 丁丑 share this Nayin name, which lets you locate the pair’s distinctive source image and conditions. If another pillar enters an older rule, record that full Jiazi, its location and the source before drawing a comparison.
Keep the reading order explicit: verify calendar inputs and the Four Pillars; retain stems, branches and hidden stems; evaluate Month Command and Day-Master structure; only then add Water Under the Stream as a Nayin layer. One Nayin name does not determine strength, Useful God, personality, work, relationships, wealth, health or event timing.
Continue reading
- Complete table of the thirty Nayin
Return to the sixty-Jiazi sequence and verify neighboring pairs.
- Compare another Water Nayin: Well Water
A shared phase does not make two images or conditions interchangeable.
- Water in ordinary Five-Phase analysis
Separate Nayin classification from actual chart relations.