What is Can Chi?
Can Chi is the system that pairs the Ten Heavenly Stems (Giáp, Ất, Bính, Đinh, Mậu, Kỷ, Canh, Tân, Nhâm, Quý) with the Twelve Earthly Branches (Tý, Sửu, Dần, Mão, Thìn, Tỵ, Ngọ, Mùi, Thân, Dậu, Tuất, Hợi) to record years, months, days and hours in the traditional East Asian calendar.
Also called: Can Chi system
What is Can Chi?
Can Chi (Chinese characters: 干支) is the short name for the combined system of Heavenly Stems (Thiên Can) and Earthly Branches (Địa Chi). The Heavenly Stems consist of ten elements: Giáp, Ất, Bính, Đinh, Mậu, Kỷ, Canh, Tân, Nhâm, Quý. The Earthly Branches consist of twelve elements: Tý, Sửu, Dần, Mão, Thìn, Tỵ, Ngọ, Mùi, Thân, Dậu, Tuất, Hợi. When a Stem is paired with a Branch in a recurring cycle, the result is a cycle of 60 combinations known as the sexagenary cycle (lục thập hoa giáp).
What is Can Chi used for?
In traditional calendrics, Can Chi is used to name and number years, months, days and hours. Each year carries a Can Chi pair, for example the year Giáp Tý, the year Ất Sửu, and after 60 years the cycle returns to the start. In the field of destiny analysis, the Can Chi of the four markers of birth (Year, Month, Day, Hour) form the Bát Tự (Four Pillars), made up of eight characters, used to analyse the relationships of Yin Yang and the Five Elements. In the I Ching (Kinh Dịch), each Heavenly Stem and Earthly Branch is also assigned properties of Yin Yang, the Five Elements, direction and season, for instance Canh is Yang Metal associated with the West and autumn, Bính is Yang Fire associated with the Ly trigram.
Why is the Can Chi cycle 60 and not 120?
Ten Stems and twelve Branches, if paired freely, would give 120 pairs, but in reality only 60 pairs appear. The reason is that Stems and Branches are paired according to the rule of Yin and Yang: a Yang Stem pairs only with a Yang Branch, a Yin Stem pairs only with a Yin Branch. Since the ten Stems divide evenly into five Yang and five Yin, and the twelve Branches divide evenly into six Yang and six Yin, the number of valid combinations is reduced to exactly 60. This is also why combinations such as Giáp Sửu or Ất Tý do not exist in standard notation.
How does Can Chi differ from Bát Tự?
Can Chi is a notation system used to record time, while Bát Tự is an interpretive method based on those notations. In other words, Can Chi is the ingredient, Bát Tự is the way it is prepared. A person can know the Can Chi of their birth year without any need for Bát Tự; conversely, someone studying Bát Tự must master Can Chi before moving into analysis of the Five Elements, clashes and combinations, or the Day Master (Nhật Nguyên).
Is Can Chi only used for fortune telling?
Not exactly. Can Chi originated as a tool for counting and recording time in calendrics, and only later was it extended into interpretive fields such as Bát Tự, the I Ching, feng shui and date selection. These interpretive applications belong to the domain of traditional knowledge and are for reference; they have not been verified by modern science, so they are best regarded as a cultural perspective.
How do different schools understand Can Chi?
- The calendrical understanding: Can Chi is purely a system for counting time, carrying no meaning of good or bad fortune. Those who follow this understanding use Can Chi only to record years, months, days and hours, to calculate the 60-year cycle, and to cross-reference the lunar and solar calendars.
- The destiny-analysis understanding: Can Chi carries its own Yin Yang and Five Elements energy, and each Stem and each Branch has its own nature, direction and season. From this, Bát Tự is formed, used to interpret fortune, character and the relationships of clash and combination between the pillars.
- The I Ching understanding: Can Chi is linked to trigrams and lines, for example Canh is linked to the West, autumn and the Càn trigram; Mậu is linked to the Bác trigram and the Cấn trigram; Bính is linked to the Ly trigram. This understanding places Can Chi within the symbolic-number system of the I Ching.
What are related articles?
- Heavenly Stem Canh, its Yin Yang and Five Elements properties in the I Ching
- Heavenly Stem Tân, its Yin Yang and Five Elements properties in the I Ching
- What is Bát Tự (Four Pillars)? How to read destiny through the eight Can Chi characters
- What is the Hour Pillar in Bát Tự (Four Pillars)?
- Heavenly Stem Mậu: Yin Yang and Five Elements properties in the I Ching
- What is the Day Pillar in Bát Tự (Four Pillars)?
- Heavenly Stem Bính: Yin Yang and Five Elements properties in the I Ching
What are the first 12 Can Chi pairs in the 60-cycle?
| Order | Pair | Heavenly Stem | Earthly Branch | Yin / Yang | Five Elements of the Stem |
|---|---|---|---|---|---|
| 1 | Giáp Tý | Giáp | Tý | Yang | Wood |
| 2 | Ất Sửu | Ất | Sửu | Yin | Wood |
| 3 | Bính Dần | Bính | Dần | Yang | Fire |
| 4 | Đinh Mão | Đinh | Mão | Yin | Fire |
| 5 | Mậu Thìn | Mậu | Thìn | Yang | Earth |
| 6 | Kỷ Tỵ | Kỷ | Tỵ | Yin | Earth |
| 7 | Canh Ngọ | Canh | Ngọ | Yang | Metal |
| 8 | Tân Mùi | Tân | Mùi | Yin | Metal |
| 9 | Nhâm Thân | Nhâm | Thân | Yang | Water |
| 10 | Quý Dậu | Quý | Dậu | Yin | Water |
| 11 | Giáp Tuất | Giáp | Tuất | Yang | Wood |
| 12 | Ất Hợi | Ất | Hợi | Yin | Wood |
The Stems run in a cycle of 10, the Branches in a cycle of 12, so a pair repeats after 60 steps rather than 120: a Yang Stem pairs only with a Yang Branch and vice versa, cutting exactly half of the combinations.
The figures in the table match the results of the lookup tools on Nhật Nguyệt.
