The Earthly Branches are twelve basic symbols
The Gan-Zhi and Saju traditions use twelve Earthly Branches.[1][2]
Their traditional sequence is:
子 · 丑 · 寅 · 卯 · 辰 · 巳 · 午 · 未 · 申 · 酉 · 戌 · 亥
This article focuses on their structural relationship to traditional timekeeping rather than turning the Branches into twelve personality types.
Month pillars are calculated separately from calendar month numbers
External traditional calendar material shows Earthly Branches being used in month notation.[2] This publication does not use a simple external month-number table as the governing rule for Saju month-pillar or month-branch calculation.
Month-pillar and month-branch calculation is not an automatic change on the first day of each Gregorian month. In this project's calculation framework it belongs to a separate layer that checks exact solar-term entry boundaries.
For that reason, no Earthly Branch is treated as directly identical to a specific Gregorian calendar month.
The Branches are linked to the twelve shichen
Traditional timekeeping divides the day into twelve shichen, each roughly two hours long.[1][2]
子 23:00–01:00 → 丑 01:00–03:00 → 寅 03:00–05:00 → 卯 05:00–07:00 → 辰 07:00–09:00 → 巳 09:00–11:00 → 午 11:00–13:00 → 未 13:00–15:00 → 申 15:00–17:00 → 酉 17:00–19:00 → 戌 19:00–21:00 → 亥 21:00–23:00
This is a traditional time-classification structure. It is not a scientifically established causal rule saying that a time interval determines personality or events.
The Branches are not reduced to zodiac personality labels
Earthly Branches are widely known through their association with zodiac animals, but one Branch alone does not determine a person's personality, aptitude, health, wealth, relationships, or future.
Likewise, a shichen correspondence does not make that time category a decisive cause of individual outcomes.
Structural classification and individual interpretation are different steps.
A complete four-season grouping is not added here
Traditional discussions connect the Earthly Branches with seasonal context.[1]
However, the currently approved canonical scope has not finalized a complete four-season grouping table for all twelve Branches.
For that reason, this article does not create a new chart such as 寅卯辰 = spring and parallel groupings for the remaining Branches.
For now, two points are enough:
twelve Earthly Branches → twelve-shichen time structure
Month-pillar calculation belongs to a separate solar-term-boundary calculation layer, not to a Gregorian month-number chart.