The ten Heavenly Stems, sometimes called the Celestial Stems, date back to the very earliest records of writing in China. These characters appear to be very old indeed and seem to have marked the days of a ten day week. The characters themselves are not terribly common in modern Chinese, with only one appearing in the first 1000 characters, and five more appearing in the 3000 most common characters.1
As noted in Ban on Building B, these characters do perform the role of an alternative ordinal system, in much the same way that A,B,C do in English. They are also a crucial component of the system of dates used for a good chunk of Chinese history which I’ll touch upon in a future post.
My own reaction to these words, when I first encountered them, was to largely ignore them; after all, they seemed to be largely useless and irrelevant when I was grappling with much more important things.
I could just get by with a vague sense that the first three or four were some kind of sequence, and I’d work any such sequence out from context when I needed to.
I now think that was a mistake. It was a mistake for two fairly obvious reasons (and one more):
1) Most of these characters crop up pretty regularly as components of more common characters.
2) This is just the sort of cultural information which is likely to either be useful at some point, or simply enhances ones understanding of the language and environment.
3) Learning them is easy.
Try counting on the fingers of your left hand, as pictured above.
Just go round the cycle and you’ll have them down in no time.
In the following list, the Heavenly Stem, with its frequency rank in brackets, is followed by other common (top-3000) characters in which it features.
甲 (1167) 鸭／鴨，押，闸／閘
乙 (1658) 也， 艺／藝, 亿／億，忆／憶，挖，乞
丙 (1967) 病，陋，柄，炳
丁 (1070) 打，订／訂，宁／寧，灯／燈，顶／頂，厅／廳，亭，盯，钉／釘，叮，贮／貯
戊 (—-) 成，岁／歲，威，灭／滅，戚，咸，茂，蔑
庚 (—-) 康，唐，庸
辛 (1313) 亲／親，办／辦，辩／辯，辞／辭，辟，辣，宰，瓣，僻，辫／辮，辜
壬 (—-) 任，庭，凭／憑，廷，淫
癸 (—-) No common characters, though I guess 向日葵 appears often enough, and both 登 and traditional 發 employ 癶. The lower part was originally 矢 but is the first stroke was dropped leaving 天.
Now I’m not trying to suggest that the student should learn these characters at the very beginning of their studies. There are plenty of more useful, simple characters that occur much more frequently than these. Two radicals that are learned early in any Chinese programme, I presume, are 木 mù and 日 rì, and each of these crops up in over 150 of the 3000 most commonly used characters.
As I didn’t go through a formal programme at the beginning of my Chinese studies, I’d be most interested to hear from students and teachers when such characters are introduced and whether they think memorising a ‘set’ like this would be helpful and worthwhile.
If, like me, you never bothered to learn them, why not invest ten or twenty minutes in locking them away now? You never know when they might come in useful.
In the next post I’ll be looking at the Earthly Branches.
1The frequency numbers used throughout this post are taken from the Wenlin dictionary. The producers of Wenlin point out that these numbers are only a guide and not to be taken too seriously.
2Note that 己 jǐ，已 yǐ，巳 sì, are classified under the same radical, though recognising the difference might yet be useful.