The Rat in the Chinese Zodiac
First of the twelve, keeper of midnight
- Earliest record
- the 210s BCEThe daybook (rishu) from Shuihudi tomb 11, Yunmeng, deposited about 217 BCE, pairs the branch with the animal in its 'Robbers' section; the Fangmatan Qin daybooks, dated by their readers to the late Warring States or Qin, carry the same pair.
The toe reason often given for the rat's first place, four toes in front and five behind, is set out in Lang Ying's sixteenth-century Qixiu leigao. He ended by calling his explanations a private surmise he had not seen in any book.
Lang Ying, Qixiu leigao, juan 4, 'The twelve animals' (Wikisource text); Lang Ying's dates from Chen Shan's preface to the Qixiu xugao as cited on Chinese Wikipedia.
The rat, first of the twelve animals paired with the earthly branches; it stands for the branch zi.
More context
The rat belongs to zi, the first of the twelve earthly branches, which also name the twelve double hours of the day; zi is the hour round midnight. The pairing is already written in Qin almanacs. The daybook from Shuihudi tomb 11, buried about 217 BCE, says "zi is the rat". It describes a thief of a zi day as pointed-mouthed and sparse-whiskered, hiding in holes in walls. Around 80 CE Wang Chong recorded the rat's pairing with water. In the Ming, Lang Ying explained its first place by its toes. Recent rat years began in 1996 (bingzi), 2008 (wuzi) and 2020 (gengzi); the next is 2032 (renzi). Each is counted from the lunar New Year.
Light
Lang Ying set the rat at midnight, where one day turns into the next: the sign stands at the cycle's hinge, holding old night and new day together.
Shadow
The Qin almanac's rat-day thief has a pointed mouth and sparse whiskers and hides in wall holes under dung: the sign once served to sketch a burglar's face.