On Yin-Yang Birth and Death (Yin Yang Sheng Si)

Why Yang Runs Forward and Yin Runs Back

The twelve stages of a stem — birth, bathing, cap and sash, office, emperor's prosperity, and on to death, storage and extinction — are the backbone of every later judgement about strength. Here Shen explains why they run forward for yang and backward for yin, and why what is born for yang is exactly what dies for yin. He then translates the twelve names into images of a human life. The chapter closes on the practical rule: a day master need not sit on its prosperous month. A root anywhere in the four pillars will do, and a storage branch counts as a root.