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# What Are the Heavenly Stems?

What Are the Heavenly Stems?

The Heavenly Stems are ten symbols used in the Can Chi (Stem and Branch) system of East Asian calendrics. Their full name is the Ten Heavenly Stems, comprising: Giáp, Ất, Bính, Đinh, Mậu, Kỷ, Canh, Tân, Nhâm, Quý. Each Heavenly Stem carries a Yin-Yang attribute and one of the Five Elements (Metal, Wood, Water, Fire, Earth), forming the foundation for interpreting many systems of metaphysics such as Bát Tự (BaZi), Kinh Dịch (the I Ching) and phong thủy (feng shui).

Origin and role in calendrics

By tradition, the Heavenly Stems appeared very early in ancient Chinese culture, initially used to count days. When combined with the twelve Earthly Branches, they form a cycle of 60 (the sexagenary cycle) used to record years, months, days and hours. For example, a year is called the year of Giáp Tý, Ất Sửu, and so on. In Bát Tự (Four Pillars), each pillar consists of one Heavenly Stem and one Earthly Branch, reflecting different aspects of a person's destiny.

What are the ten Heavenly Stems and their attributes?

Each Heavenly Stem has its own characteristics:

• Giáp: Yang Wood, symbolising a large tree, beginnings and growth.
• Ất: Yin Wood, soft grass, flexible yet enduring.
• Bính: Yang Fire, the radiant sun, spreading power.
• Đinh: Yin Fire, a small flame, gentle and warm light.
• Mậu: Yang Earth, solid ground, the centre and nourishment.
• Kỷ: Yin Earth, soft soil, nourishing and transforming.
• Canh: Yang Metal, raw metal, strength and decisiveness.
• Tân: Yin Metal, refined metal, sharp yet inward.
• Nhâm: Yang Water, a great river, the sea, spreading outward.
• Quý: Yin Water, soft water, flexible and hidden.

These attributes are applied in the interpretation of Kinh Dịch, Bát Tự and many other fields.

How do the Heavenly Stems differ from the Earthly Branches?

The Heavenly Stems and Earthly Branches usually go together but have different roles. The Heavenly Stems number 10 symbols, carrying a "heavenly" quality, expressing energy, nature and interactive relationships. The Earthly Branches number 12 symbols, carrying an "earthly" quality, tied to specific space, time and the zodiac animals. Their combination forms the complete Can Chi system. In addition, the Heavenly Stems also differ from the Five Elements in that each element has two stems (yin and yang), for example Wood has Giáp (yang) and Ất (yin).

Points to note when learning what the Heavenly Stems are

Information about the Heavenly Stems belongs to traditional knowledge and is for reference; it has not been verified by modern science. Readers should approach it in a spirit of cultural learning, and should not treat it as absolute truth or use it to decide important matters in life.

How do different schools understand it?

• Understanding in calendrics: The Heavenly Stems are a purely symbolic system for recording days, months and years, combining with the Earthly Branches to create the 60-year cycle, with no predictive meaning.
• Understanding in metaphysics: Each Heavenly Stem carries Yin-Yang and Five Element energy, influences destiny and can be interpreted in Bát Tự and Kinh Dịch.
• Understanding in folk culture: The Heavenly Stems are tied to natural phenomena and people, often used to choose days and read ages, but mainly carry symbolic meaning.

Related articles

• The Heavenly Stem Canh, its Yin-Yang and Five Element characteristics in Kinh Dịch
• The Heavenly Stem Tân, its Yin-Yang and Five Element characteristics in Kinh Dịch
• What is the Hour Pillar in Bát Tự (Four Pillars)?
• The Heavenly Stem Mậu: Yin-Yang and Five Element characteristics in Kinh Dịch
• What Are the 12 Zodiac Animals? Meaning and How to Calculate Age by Earthly Branches
• The Heavenly Stem Đinh, its Yin-Yang and Five Element characteristics in Kinh Dịch
• The Heavenly Stem Quý: Yin-Yang and Five Element characteristics in Kinh Dịch
• The Heavenly Stem Ất: Yin-Yang and Five Element characteristics in Kinh Dịch
• The Heavenly Stem Giáp: Yin-Yang and Five Element characteristics in Kinh Dịch
• The Heavenly Stem Kỷ, its Yin-Yang and Five Element characteristics in Kinh Dịch
• The Heavenly Stem Nhâm: Yin-Yang and Five Element characteristics in Kinh Dịch
• The Heavenly Stem Bính: Yin-Yang and Five Element characteristics in Kinh Dịch

What does the table of the 10 Heavenly Stems contain?

Stems in odd positions (Giáp, Bính, Mậu, Canh, Nhâm) are Yang; even positions are Yin. Every two adjacent stems share one element.

The figures in the table match the results of the lookup tools on Nhật Nguyệt.