Qi Yun (Luck Pillar Start): When the First Decade Begins
Definition
Qi Yun is the age at which a person's first [Luck Pillar](/bazi/glossary/da-yun) begins. Before it, one runs the childhood limit (the [Minor Luck](/bazi/glossary/xiao-yun)); only after Qi Yun is the Luck Pillar read. The starting age varies by individual and must be computed precisely from the birth moment.How It Is Derived
The traditional method has two steps: 1. **Direction:** by "yang-male and yin-female go forward; yin-male and yang-female go in reverse" — the birth-year stem's polarity and the person's sex decide whether the Luck Pillars run forward or backward. 2. **Age:** for forward, count the days from birth to the **next** solar-term node; for reverse, to the **previous** node; convert by "three days = one year, one day = four months" to get the starting age.Accuracy therefore depends on a precise birth moment, true-solar-time correction, and exact solar-term timings. A calculator handles this.