The Ten Heavenly Stems

天干 · One by One

Everything in a BaZi chart is written in a script of ten Heavenly Stems (天干) and twelve Earthly Branches (地支). The stems are the visible voices; every character you see on top of a pillar is one of these ten. If you cast your own chart, you will meet one of them as your Day Master. Here is each stem in one breath, with its element, polarity and characteristic flavor.

The five elements, twice

Ten stems = five elements, each in a Yang and a Yin shade. The Yang version is the elder sibling — forceful, expansive, made to lead its element. The Yin version is the younger — flexible, adaptive, skilled at influence rather than force.

Wood

Jia (甲, Yang Wood) — the straight trunk. Upright, principled, growth-driven; bends only deliberately and breaks before it bends.
Yi (乙, Yin Wood) — the vine and the flower. Flexible, sensitive, socially graceful; grows around obstacles rather than through them.

Fire

Bing (丙, Yang Fire) — the sun at noon. Warm, visible, generous; lights up a room and others find their way by it.
Ding (丁, Yin Fire) — the lamp and the candle. Steady inner warmth; cares for what is close, endures the night quietly.

Earth

Wu (戊, Yang Earth) — the mountain and the embankment. Solid, reliable, slow to move; once positioned, hard to shift.
Ji (己, Yin Earth) — the field and the garden. Nurturing, adaptable, productive; quietly manages what it is given.

Metal

Geng (庚, Yang Metal) — the axe and the raw ore. Decisive, blunt, unafraid of conflict; values truth over comfort.
Xin (辛, Yin Metal) — the jewelry and the fine blade. Refined, perceptive, precise; cuts with elegance rather than force.

Water

Ren (壬, Yang Water) — the river and the ocean. Flowing, ambitious, hard to contain; carries a situation forward.
Gui (癸, Yin Water) — the rain and the mist. Deep, intuitive, subtle; nourishes people before they notice they were dry.

Reading your own stem

Your Day Master being, say, Ren means "a river" is the character at the center of your chart: an element and polarity that shape how every other character treats you. But one stem alone is not a horoscope — a Ren chart in spring, with Water everywhere, reads very differently from the same Ren born in summer with the charts leaning to Fire. The stem gives you your lead actor; the season and the other seven characters give you the plot.

Beyond the one-lines

The one-line flavors above are the traditional starting points — useful shorthand, not physics. Every stem is also defined by what it does: what it nourishes, what it produces, what it manages and what presses on it. That relationship web is exactly what the Ten Stars name, and it is worth more in a reading than any single adjective.

Cast your chart to meet your stem — your Day Master and its element are named in English at the top of the result.