A revolutionary transformation occurred. Xu Ziping introduced the Hour Pillar, establishing the Four Pillars Eight Characters system and shifting from Year-centered to Day-centered (Day Master) analysis. Ancient and modern methods coexisted.
Modern Model (Day Master / Four Pillars)
960 – 1127 CE
Birth of the Modern Model
Masters & Contributions
Xu ZipingMaster of BaZi
Key Works
Origin of Yuanhai Ziping
Historical Contribution
Established the Day Stem as central, focusing on Five Elements interaction. Reformed Li Xuzhong's Nayin method to create "Ziping Method."
Zhang Yong
Key Works
Yuzhao Dingzhen Jing
Historical Contribution
Continued the ancient method with refined interpretations—a key transitional work.
Li Quan
Key Works
Commentary on Luoluozi
Historical Contribution
Annotated ancient classics, preserving early theoretical essence.
Anonymous
Key Works
Tianyuan Xiuqi Wuxian Jing
Historical Contribution
Important Song dynasty text discussing stem-branch elegance and Nayin relationships.