The Chinese System of Heaven Stems and Earth Branches


What Heaven Stems & Earth Branches Are

Chinese have traditionally made use of a specialized number system that counts from 1 to 60. The numbers in this system consist of a first digit from a series of ten "Heaven Stems" (tiāngān 天干) and the second from a series of twelve "Earth Branches" (dìzhī 地支).

Here is a list of the Chinese characters used, with their pronunciations. In our examples we will represent the Heaven Stems with upper case letters (A through J) and the Earth Branches with lower case letters (a through l).

Cautionary note for students of Chinese: The tiāngān jĭ (also used in the common word 自己 is not quite the same as the character yĭ (as in 已經). (The box part of jĭ is entirely open. The box part of yĭ is half closed.) To make matters worse, both look very much like the dìzhī sì (with the box entirely closed).
List of the 10 Heaven Stems (Tiāngān 天干)
Jiă Bĭng Dīng Gēng Xīn Rén Guĭ
List of the 12 Earth Branches (Dìzhī 地支)
chŏu yín măo chén wèi shēn yŏu hài
a b c d e f g h i j k l

How To Count in Heaven Stems and Earth Branches

The number 1 is expressed as the first Heaven Stem plus the first Earth Branch (Aa). The number 2 is composed of the second Heaven Stem plus the second Earth Branch (Bb). And so on, up to 10 (Jj).

1 2 3 4 5 6 7 8 9 10
Aa Bb Cc Dd Ee Ff Gg Hh Ii Jj
甲子 乙丑 丙寅 丁卯 戊辰 己巳 庚午 辛未 壬申 癸酉

When we reach 10, we have used up our Heaven Stems (upper case letters), but have two Earth Branches (lower case letters k and l or chracters xū and hài ) still to go. So the series continues with the Earth Branches shifted over by two compared with the Heaven Stems:

11 12 13 14 15 16 17 18 19 20
Ak Bl Ca Db Ec Fd Ge Hf Ig Jh
甲戌 乙亥 丙子 丁丑 戊寅 己卯 庚辰 辛巳 壬午 癸未

As we start the 20s we are mismatched by four from the original series. So 21 is Ai, 22 is Bj, and so on.

It takes the count of 60 to come out even. Sixty-one is once again Aa.

What This Is Used For

What is the good of a system which can count only from 1 to 60?

Occasionally it was used to number the folios of a large literary work divided into sixty volumes, for example, or the divination poems used as answers to prayers in temples. But most importantly, they were used to count days and years and hours, thus arbitrarily aranging time into sixty-unit "cycles" repeating into the infinite past and future. Each year is numbered in an ever repeating 60-element cycle. So is each month, day, and hour. Similarly, Heaven Stems and Earth Branches provided a progression of spaces in the circle of the horizon (each pair corresponding to 6 degrees in the western division of a circle into 360 degrees). Thus space and time could both be arbitrarily associated with units of measurement.

In fortune telling, hours, days, or years associated with some pairs of Heaven Stems and Earth Branches are considered to be favorable or unfavorable for various activities, especially for people born at hours, days, or years associated with other combinations of Heaven Stemps and Earth Branches. (Obviously, there is enormous potential for complexity in this, potential that is well exploited by traditional fortune tellers.)

Heaven Stems. Because there are ten Heaven Stemps, pairs of Heaven Stems are aligned with the five elements and hence with the various other things connected with the "five elements" complex, described elsewhere on this web site. The things associated with the "five elements" range from flavors and colors to virtues, organs, and notes of the scale. Through the linkages between Heaven Stems and five elements, time and direction was even more subtly linked with these other features of human experience.

Droll Trivium: Because there are ten Heaven Branches, and because the cycle is used to count years, the Heaven Branch is predictable from the western year. A Western year ending in 0 always corresponds to a Chinese G (gēng ) year (or more exactly to the greater part of it does, since Western and Chinese New Years do not quite coincide). Thus a Western year ending in 1 will be a Chinese H (xīn ) year, a year ending in 2 an I (rén ) year, and so on.

Earth Branches. The twelve Earth Branches are aligned with the famous year animals used in Chinese astrology. (Thus most of 2002 falls into the "year of the horse.") But they are also associated with the constellations used in the West for signs of the zodiac, and with twelve Chinese hours of the day (each two hours long by international caluculation), and with directions around the horizon. Here are some correlations:

Earth Branch Year Animal Constellation Time of Day Direction
a rat Aries 11pm-1am N
b ox Taurus 1-3 NNE
c tiger Gemini 3-5 ENE
d hare Cancer 5-7 E
e dragon Leo 7-9 ESE
f snake Virgo 9-11 SSE
g horse Libra 11am-1pm S
h sheep Scorpio 1-3 SSW
i monkey Sagittarius 3-5 WSW
j cock Capricorn 5-7 W
k dog Aquarius 7-9 WNW
l pig Pisces 9-11 NNW

The Bottom Line:

Through such correlations, it is possible to link time and space to each other, to the stars, and to the various things that align with the five elements. This in turn creates a vast number of petty strategies for running each day of one's life in accord with a culturally defined structure of the the cosmos.

For the social scientist there are two absolutely critical conclusions to be drawn.

  1. Psychological Implications: Having procedures for running one's life in accord with the cosmos creates the [false] impression of being able to control one's fate, contributing to peace of mind for some people, but a heightened anxiety for others. Most social scientists believe the peace of mind result is more important.
  2. Social Implications: Paying attention to what one's neighbors believe are lucky and unlucky times and places constitutes a continuing public (and personal) declaration of cultural conformity and of subordination of individual desire to group understandings. Social integration thrives on conformity and languishes in its absence. The symbolic demonstration and reinforcement of broad conformity (loyalty) helps sustain the levels of cooperation necessary for ordered social life.


Heavenly Stems and Earthly Branches

Table of Signs of the Zodiac - Encyclopedia

Chinese Calendar - History and Traditions

⇑⇑ Chinese Calendar Article Archive

✍: David K. Jordan

2021-12-08, 2409🔥, 0💬