What is the historical evolution and origin of BaZi (Four Pillars of Destiny)?
八字（四柱预测学）的历史演变与起源是什么？
The roots of BaZi date back thousands of years to ancient China, where the Heavenly Stems (Tian Gan) and Earthly Branches (Di Zhi) were first utilized during the Shang dynasty for recording days, months, and years.
During the Tang dynasty, scholar Li Xuzhong revolutionized destiny analysis by evaluating a person's birth year, month, and day pillars (Three Pillars) to determine elemental configurations.
In the Song dynasty, master Xu Ziping further advanced the art by introducing the Hour pillar (completing the Four Pillars) and making the Day Master (the stem of the day of birth) the absolute center of the chart analysis, giving birth to modern BaZi (Ziping Bazi).
八字的渊源可追溯至数千年前的中国古代，当时天干与地支在商代即被广泛用于纪日、纪月与纪年。
在唐代，学者李虚中通过考察出生年月日（三柱）的干支五行生克来推断命理，奠定了早期推命体系的基础。
到了宋代，徐子平大师进一步将时柱纳入其中，从而形成了完整的“四柱八字”，并确立了以“日主（日干）”为核心的论命方法，世称“子平八字”，沿用至今。