十二時辰的産生與制度化

The Formation and Institutionalization of the Twelve Shichen(Double Hours)

中國古代的十二時辰,是一種均分全天時段且不隨季節變化的匀定時制。十二辰原指方位,在秦漢《日書》已經開始與時稱對應,用於占卜,但性質與後世的十二時辰不同,並非其源頭。十二時辰萌生於西漢式占和曆算中的"日加"十二辰,也稱"加時"。這在當時僅是一種理念性的時間系統,未能迅速流行。直到梁武帝改革時制,將漏刻與加時結合成爲辰刻記時法,纔正式將十二辰作爲時間的名稱。這種新的記時法,被隋代官方曆法吸收,至唐代中葉以後逐漸用於制度規定和日常政務,其匀定性質則長期未能貫徹。

The twelve shichen or double hours in premodern China were a system of constant time reckoning based on equal and unvarying divisions of the day. The twelve chen or"chronograms"originally denoted spatial directions and started to be correlated with time divisions for divinatory purposes in the rishu or"daybook"texts from the Qin Han period. But they cannot be seen as the direct origin of the later twelve shichen because of their different nature. The twelve shichen emerged from the notion of rijia or"the sun occurring at"one of the twelve chen,also known as the jiashi or"occurrence double hours",for designating the sun’s positions as well as the time of the day in Western Han shi or cosmic board divination and calendrical astronomy. The jiashi remained mainly an idea,without being put into common practice in the following centuries. The twelve chen obtained the function as signs of time only when the Emperor Wu of the Liang reformed the reckoning of time,combining the jiashi with water clock marks and thus inventing a new format for representing times within a day. This new format was absorbed into the official calendar under the Sui and then,from the mid Tang period onward,gradually became prevalent in institutional regulations as well as practices of daily governmental affairs. But,due to technological and socio cultural factors,the intended constancy of the twelve shichen would not be fully realized for a very long time to come.