Yin and Yang 阴阳

Yin and yang are complementary polarities rather than opposites in conflict: shaded and sunlit sides of the same hill, the receptive and the active phase of the same process. In the calendar they operate as a strict alternation. The stems alternate yang and yin down the list, and so do the branches, starting yang at Zi.

The alternation is what keeps the sexagenary cycle to sixty combinations instead of 120: a yang stem only ever pairs with a yang branch. In chart reading, polarity is what splits each of the five element relationships into two of the Ten Gods, and it changes the flavour of a relationship without changing its direction — same-polarity pairs are read as more direct and blunt, opposite-polarity pairs as smoother.

Every sign profile on this site states the polarity of its branch, and the pillar notation in the chart tool depends on the rule that polarities must match.

• A yang branch: the Dragon (Chen)
• Polarity shown on every pillar