Heavenly Stem

천간 · 天干

The upper character of a pillar — one of ten, showing what is visible and expressed.

There are ten stems, made by pairing each of the five elements with a yang and a yin form: Yang Wood, Yin Wood, Yang Fire, Yin Fire, and so on down to Yin Water.

Stems are the open part of the chart. What sits in a stem is what other people can see in you, and what you can reach for deliberately.