Building Blocks
Hidden Stems
The one to three heavenly stems concealed within each earthly branch.
Hidden stems are the one to three heavenly stems concealed inside each earthly branch, with the dominant one (the main qi) matching the branch's own element. They let a branch participate in Ten-God and pattern analysis, and a stem is said to be "rooted" when its element also appears in the hidden stems below. The main qi is stable across sources, but the secondary hidden-stem assignments vary by source and school.