What is Earthly Branches and where does it come from?
Earthly Branches (地支) is a system of 12 symbols used to mark time, direction, and interactive relationships in East Asian culture. Ancient people associated each Branch with a familiar animal, creating the image of the 12 zodiac animals: Rat (Tý), Ox (Sửu), Tiger (Dần), Rabbit or Cat (Mão), Dragon (Thìn), Snake (Tỵ), Horse (Ngọ), Goat (Mùi), Monkey (Thân), Rooster (Dậu), Dog (Tuất), Pig (Hợi). The exact origin of this system is not clearly determined in historical records, but it appeared very early in ancient calendrics and is closely tied to agriculture, astrology, and spiritual life.
How are Earthly Branches used?
In calendrics, Earthly Branches combine with the 10 Heavenly Stems (Giáp, Ất, Bính, Đinh, Mậu, Kỷ, Canh, Tân, Nhâm, Quý) to form a 60-year cycle called the sexagenary cycle. Each year, month, day, and hour has its own Stem-Branch pair. In Bazi (Four Pillars), the birth hour is determined based on the day's Stem and the Earthly Branches system, forming the Hour Pillar that reflects later life and late relationships. Additionally, each Branch is associated with a time period in the day (each Branch corresponds to two hours) and a specific direction.
What are the relationships between Earthly Branches?
Earthly Branches do not exist independently but interact according to many rules. Three Harmony is a group of three Branches of the same element, for example Monkey - Rat - Dragon form the Water frame, Tiger - Horse - Dog form the Fire frame, Snake - Rooster - Ox form the Metal frame. Six Harmony refers to six pairs of mutually compatible Branches, such as Rat - Ox, Rabbit - Dog, Snake - Monkey. Four Clashes refers to four Branches in direct opposition, such as Rat clashes with Horse, Rabbit clashes with Rooster. Six Harms refers to six pairs of hidden conflict, such as Rat - Goat. These relationships are widely applied in astrology, date selection, age selection, and other occult fields.
Distinguishing Earthly Branches from Heavenly Stems and the 12 zodiac animals
Earthly Branches are one half of the Stem-Branch system, while Heavenly Stems are the other half. Heavenly Stems consist of 10 elements, Earthly Branches consist of 12 elements; when combined they create 60 combinations. It is necessary to distinguish Earthly Branches from the 12 zodiac animals: the 12 zodiac animals are a folk way of using animal images to refer to the 12 Earthly Branches, but Earthly Branches themselves are a more abstract symbol system used in calendrics and various divination methods. Additionally, Earthly Branches differ from the concept of "zodiac age" in daily life, which is simply a basic application of Earthly Branches to age calculation.
Note: This is traditional knowledge for reference, not scientifically verified, especially when applied to divination and occultism.