2637 BCE

Chinese calendar

• Lord Huangdi, the Yellow Emperor, decreed
• in 2637 BCE
• a lunisolar calendar governing months, holidays,
• and auspicious dates.
• Each day begins at midnight.
• Each month begins
• on the day of the dark moon.
• Each year begins with the month
• between winter solstice
• and spring equinox.
• A leap month is inserted whenever
• a year has 13 new moons.
• Each year is divided into 24 solar terms.
• Each solar term is divided into three groups of days
• called pentads.
• Most years have 12 months; leap years have 13.
• Most years have between 353 and 355 days;
• leap years have between 383 and 385.

Celestial stems and terrestrial branches

• The years have sixty names
• using ten celestial stems
• (having no translations in English)
• and twelve terrestrial branches
• (having names of beasts)
• so that every sixty-year cycle
• starts with jia-zi
• and ends with gui-hai
• and contains six years of the rat
• six of the ox
• six of the tiger
• six of the hare
• six of the dragon
• six of the snake
• six of the horse
• six of the sheep
• six of the monkey
• six of the rooster
• six of the dog
• and six of the pig.

• 1. jia-zi (rat)	2. yi-chou (ox)	3. bing-yin (tiger)	4. ding-mao (hare)	5. wu-chen (dragon)
  6. ji-si (snake)	7. geng-wu (horse)	8. xin-wei (sheep)	9. ren-shen (monkey)	10. gui-you (rooster)
  11. jia-1u (dog)	12. yi-hai (pig)	13. bing-zi (rat)	14. ding-chou (ox)	15. wu-yin (tiger)
  16. ji-mao (hare)	17. geng-chen (dragon)	18. xin-si (snake)	19. ren-wu (horse)	20. gui-wei (sheep)
  21. jia-shen (monkey)	22. yi-you (rooster)	23. bing-1u (dog)	24. ding-hai (pig)	25. wu-zi (rat)
  26. ji-chou (ox)	27. geng-yin (tiger)	28. xin-mao (hare)	29. ren-chen (dragon)	30. gui-si (snake)
  31. jia-wu (horse)	32. yi-wei (sheep)	33. bing-shen (monkey)	34. ding-you (rooster)	35. wu-1u (dog)
  36. ji-hai (pig)	37. geng-zi (rat)	38. xin-chou (ox)	39. ren-yin (tiger)	40. gui-mao (hare)
  41. jia-chen (dragon)	42. yi-si (snake)	43. bing-wu (horse)	44. ding-wei (sheep)	45. wu-shen (monkey)
  46. ji-you (rooster)	47. geng-1u (dog)	48. xin-hai (pig)	49. ren-zi (rat)	50. gui-chou (ox)
  51. jia-yin (tiger)	52. yi-mao (hare)	53. bing-chen (dragon)	54. ding-si (snake)	55. wu-wu (horse)
  56. ji-wei (sheep)	57. geng-shen (monkey)	58. xin-you (rooster)	59. ren-1u (dog)	60. gui-hai (pig)

God, myth, man

• If Huangdi were a god,
• then his holidays and auspicious days
• would be ordained, sacred, and blessed.
• If Huangdi were a myth,
• then what is this living pattern of days
• that we attribute to him?
• If Huangdi were a metaphor,
• then his calendar would show how things could be
• both rational and aligned with the universe.
• If Huangdi were a man,
• why should we not say
• a god could be anything he likes?
• Why couldn’t a god
• play the part of an emperor
• and take credit for another’s work?