Celestial stem

The ten Celestial Stems (zh-cp|c=|p=tiāngān), sometimes known as Heavenly Stems, are the elements of an ancient Chinese cyclic character numeral system: Jia (甲), Yi (乙), Bing (丙), Ding (丁), Wu (戊), Ji (己), Geng (庚), Xin (辛), Ren (壬), Gui (癸). They were first used for dates in the Shang Dynasty, and are now used with the twelve Earthly Branches in the Sexagenary cycle. They are associated with the concepts of yin and yang and the Five Elements.

Table

Origin

The Shang people believed that there were ten suns, each of which appeared in order in a ten-day cycle (旬; xǔn). The Heavenly Stems were the names of the ten suns, and were found in the given names of the kings of the Shang. Some historians think the ruling class of the Shang had ten clans, but it is not clear whether their society reflected the myth or vice versa. The associations with Yin-Yang and the Five Elements developed later, after the collapse of the Shang Dynasty.

The literal meaning of the characters was roughly as follows: [William McNaughton. "Reading and Writing Chinese." Tokyo: Charles E. Tuttle, 1979.]

Current usage

The Stems are still commonly used nowadays in China in counting systems similar to the way the alphabet is used in English. For example:
* Students' grades: with an additional "Yōu" ( "Excellence") before "Jiǎ"　(Japan: yū).
* Names in legal documents and contracts where English speakers would use A, B, C, etc.
* Choices on multiple choice exams, surveys, etc.
* Organic chemicals (e.g. methanol: 甲醇 "jiǎchún"; ethanol: 乙醇 "yǐchún")
* Diseases (Hepatitis A: 甲型肝炎 "jiǎxíng gānyán"; Hepatitis B: 乙型肝炎 "yǐxíng gānyán")
* Sports leagues (Serie A: 意甲 "yìjiǎ")
* Vitamins (although currently, in this case, the ABC system is more popular)
* Characters conversing in a short text (甲 speaks first, 乙 answers)

China, Korea and Japan also use heavenly stems on legal documents in this way. In Korea, letters "gap" (甲) and "eul" (乙) are consistently used to denote the larger and the smaller contractor (respectively) in a legal contract, and are sometimes used as synonyms for such; this usage is also common in the Korean IT industry.

ee also

*Chinese numerals

Notes

External links

* [http://www.hko.gov.hk/gts/time/stemsandbranches.htm Heavenly Stems and Earthly Branches - Hong Kong Observatory]