Sexagenary cycle

Sexegenary cycle

Japanese: 干支 Kan-shi or E-to

From ancient times China had two series of characters used for numbering (not for numbers!). One is the "ten stems" （jik-kan 十干), the other is the "twelve branches" (jûni-shi 十二支). They were combined to make a cycle of 60, the sexegenary cycle. These series spread over east and south-east Asia and were early taken over by the Japanese as part of the Chinese culture. They are still known in Japan, though since the Meiji period (1868-1912) their use has been very limited.

TheTwelve Branches (Jûni-shi 十二支)

general

The shi characters, translated variously as "branches," "zodiacal characters," "horary characters," etc. are a series of twelve characters used for various "cyclic" purposes. They were used for indicating direction, time, and, together with the kan, for indicating years and days. Often, though, days and years are referred to by the shi element only, without the kan. The shi early on became associated with animals, but the characters for the shi and the animals are completely distinct.

Table

The Twelve Branches 十干

No.	Kanji	Kun	On	Time		Direction
1	子	ne	shi	23:00- 1:00	0:00	N (0º)	rat
2	丑	ushi	chû	1:00- 3:00	2:00	30º	ox
3	寅	tora	in	3:00-5:00	4:00	60º	tiger
4	卯	u	bô	5:00-7:00	6:00	E (90º)	hare
5	辰	tatsu	shin	7:00-9:00	8:00	120º	dragon
6	巳	mi	shi	9:00-11:00	10:00	150º	snake
7	午	uma	go	11:00-13:00	12:00	S (180º)	horse
8	未	hitusji	bi	13:00-15:00	14:00	210º	sheep
9	申	saru	shin	15:00-17:00	16:00	240º	monkey
10	酉	tori	yû	17:00-19:00	18:00	W (270º)	bird
11	戌	inu	jutsu	19:00-21:00	20:00	300º	dog
12	亥	i	kai	21:00-23:00	22:00	330º	boar
Kun are Japanese readings, which are normally used. On are Chinese readings. NE, SE, SW, and NW are 丑寅 (ushi-tora), 辰巳、未申、and 戊亥.

The Ten stems (Jik-kan 十干)

General

The ten kan characters are the yang (陽) and yin (陰) of the five elements of wood, fire, earth, metal, and water. They were particularly used together with the shi in the sexedecimal cycle. Kô through bo were also sometimes used to designate the night hours from inu to tora. However, now in Japan their use is mainly limited to indicating rankings, as for academic grades, or for distinguishing parties in a contract (such as, "Kô agrees to pay to otsu or an agent that otsu selects..."). In these uses, the Chinese readings are used. The kan are thus not as cyclical as the shi are.

Table

Kan tables

The Ten Stems 十干

No	Kanji	Kun	On
1	甲	kinoe	kô	e. wood
2	乙	kinoto	otsu	y. wood
3	丙	hinoe	hei	e. fire
4	丁	hinoto	tei	y. fire
5	戊	tsuchinoe	bo	e. earth
6	己	tsuchinoto	ki	y. earth
7	庚	kanoe	kô	e. metal
8	辛	kanoto	shin	y. metal
9	壬	mizunoe	jin	e. water
10	癸	mizunoto	ki	y. water
Kun is Japanese reading, On is Chinese reading. e. is “elder brother of”; y. is “younger brother of.”

The sexagesimal (60-character) cycle

general

When the two cycles are used together, one gets a series of sixty pairs of characters as in the table below. (60 is the least common multiple of 10 and 12.) Note that each shi is used only with either the "elder brother" ("upper") kan or with the "youger brother" ("lower") kan: odd-numbered shi go with odd-number, or upper, kan, and even-numbered shi go with even-numbered, or lower, kan. This means, for example, that a translation of tsuchinoe-tatsu as "Earth-Dragon" instead of "Elder Brother of Earth-Dragon" is unambiguous.

These pairs are normally read using the Japanese readings, as kinoe-ne for 甲子.

From the numbers of a given K(an) and S(hi) the P(osition) in the cycle can be computed as follows: if K>=S: P = (K-S)*5+K; if S>K: P = (12+K-S)*5+K. So kanoto-u (8,4) is the 28th position, and hinoe-tatsu (3,5) is in the 53rd. One can also search in the table below.

The cycle was used to indicate days, and especially year dates. For example, 1504 was a kinoe-ne year. Dating documents by cyclic years was very common, but dating documents by cyclic days was extremely rare in Japan from what I have seen. However, as the cycle repeats every 60 years (or days), the cyclic indication is not enough to determine a date; one has to have some other information. To find the year associated with a kan-shi, use the table below and add or subtract a multiple of sixty as needed, or use the method in the year dates article.

As mentioned above, when used as a date, the Japanese reading is used for the kan-shi. However when a kan-shi is used as part of a proper name, the Chinese reading are used. Thus, the Boshin War (戊辰戦争) took place in 1868, a tsuchinoe-tatsu 戊辰 year, and all high-school baseball players dream of playing in Kôshi-en Stadium (甲子園), which opened the kinoe-ne 甲子 year of 1924. The Chinese readings used in such cases are those given in the tables above, except that 甲子 is sometimes read kasshi as well as kôshi and 乙 can be read as either itsu or otsu, by onbin it- is-, ot- or os-. So we have the 乙丑丸 Itchû-maru, "The Ship 1865".

Table

The 60-Cycle 干支

No.	Comb.	Kanji	Reading	Sample Year
1	1,1	甲子	kinoe ne	1504
2	2,2	乙丑	kinoto ushi	1505
3	3,3	丙寅	hinoe tora	1506
4	4,4	丁卯	hinoto u	1507
5	5,5	戊辰	tsuchinoe tatsu	1508
6	6,6	己巳	tsuchinoto mi	1509
7	7,7	庚午	kanoe uma	1510
8	8,8	辛未	kanoto hitusji	1511
9	9,9	壬申	mizunoe saru	1512
10	10,10	癸酉	mizunoto tori	1513
11	1,11	甲戌	kinoe inu	1514
12	2,12	乙亥	kinoto i	1515
13	3,1	丙子	hinoe ne	1516
14	4,2	丁丑	hinoto ushi	1517
15	5,3	戊寅	tsuchinoe tora	1518
16	6,4	己卯	tsuchinoto u	1519
17	7,5	庚辰	kanoe tatsu	1520
18	8,6	辛巳	kanoto mi	1521
19	9,7	壬午	mizunoe uma	1522
20	10,8	癸未	mizunoto hitusji	1523
21	1,9	甲申	kinoe saru	1524
22	2,10	乙酉	kinoto tori	1525
23	3,11	丙戌	hinoe inu	1526
24	4,12	丁亥	hinoto i	1527
25	5,1	戊子	tsuchinoe ne	1528
26	6,2	己丑	tsuchinoto ushi	1529
27	7,3	庚寅	kanoe tora	1530
28	8,4	辛卯	kanoto u	1531
29	9,5	壬辰	mizunoe tatsu	1532
30	10,6	癸巳	mizunoto mi	1533
31	1,7	甲午	kinoe uma	1534
32	2,8	乙未	kinoto hitusji	1535
33	3,9	丙申	hinoe saru	1536
34	4,10	丁酉	hinoto tori	1537
35	5,11	戊戌	tsuchinoe inu	1538
36	6,12	己亥	tsuchinoto i	1539
37	7,1	庚子	kanoe ne	1540
38	8,2	辛丑	kanoto ushi	1541
39	9,3	壬寅	mizunoe tora	1542
40	10,4	癸卯	mizunoto u	1543
41	1,5	甲辰	kinoe tatsu	1544
42	2,6	乙巳	kinoto mi	1545
43	3,7	丙午	hinoe uma	1546
44	4,8	丁未	hinoto hitusji	1547
45	5,9	戊申	tsuchinoe saru	1548
46	6,10	己酉	tsuchinoto tori	1549
47	7,11	庚戌	kanoe inu	1550
48	8,12	辛亥	kanoto i	1551
49	9,1	壬子	mizunoe ne	1552
50	10,2	癸丑	mizunoto ushi	1553
51	1,3	甲寅	kinoe tora	1554
52	2,4	乙卯	kinoto u	1555
53	3,5	丙辰	hinoe tatsu	1556
54	4,6	丁巳	hinoto mi	1557
55	5,7	戊午	tsuchinoe uma	1558
56	6,8	己未	tsuchinoto hitusji	1559
57	7,9	庚申	kanoe saru	1560
58	8,10	辛酉	kanoto tori	1561
59	9,11	壬戌	mizunoe inu	1562
60	10,12	癸亥	mizunoto i	1563

References

• Kôjien Dictionary