Closing the Cycle

The pig belongs to the san he triad with the Rabbit and the Goat and stands opposite the Snake. Because it is the last sign, the pig year is often read in popular almanacs as a year for finishing what has been begun and for enjoying the results, before the cycle restarts with the Rat. This closing position is also where the two layers of the system are easiest to see: the branch hai is a term in an abstract twelve-part cycle used in China for counting days long before any animals were attached to it, while the pig is the emblem that later came to stand for it, attested in the Qin-period Shuihudi day-books of the third century BCE. Neither layer is decorative; the animals give the system its popular life, and the branches give it the arithmetic on which the calendar and its divinatory use actually run.

The Qin-period Shuihudi bamboo day-books, excavated in Hubei province in 1975 and dated to the late third century BCE, are among the earliest surviving physical documents to pair the twelve earthly branches with specific animal names for divinatory use, predating by centuries the more familiar Han-dynasty literary references to the full twelve-animal cycle, and their discovery substantially changed modern scholarly understanding of how early the animal associations, rather than the bare branch-counting system alone, were already in active use for everyday fortune-telling.