Taiyi jinjingshi jing 太乙金鏡式經 "Classic of the method of the Golden Mirror of the Great Unity" is a book on divination written by a Tang-period 唐 (618-907) scholar called Wang Ximing 王希明. It is known that during the Kaiyuan reign-period 開元 (713-741), he was recommended as a magician and was appointed a teacher at the Hanlin Academy 翰林.
The 10-juan-long book is mentioned in the imperial bibliography Yiwen zhi 藝文志 in the official dynastic history Xintangshu 新唐書, where it is said that the book was compiled on imperial order.
The "great unity" taiyi (also written taiyi 太一) is the deity of the polestar, the highest deity of the Daoist pantheon. Knowledge about this star was important for one school of soothsayers during the Warring States period 戰國 (5th cent.-221 BCE), while others specialized on the Five Agents (wuxing 五行), geomancy (kanyu 堪輿), personality (jianchu 建除 "establishing or avoiding"), coincidence (congchen 叢辰), the calendar, or the relation between Heaven and Man (tian ren 天人).
It is believed that the great unity was the "largest dimension" (taiji 太極) encompassing the whole universe, in other words, the Dao 道 "Way". This largest dimension produced the "two items" (ermu 二目), i.e., Heaven and Earth, the latter the "four wheels" (sifu 四輔), and these produced the "eight generals" (bajiang 八將), which corresponded to the eight trigrams of the Yijing 易經 "Book of Changes". The year, months, days and hours served as spots of the outer "ropeline" (gang 綱), while the "eight generals" were used as woofs (wei 緯) in the interpretations of good and bad luck, while the warps (jing 經) were constituted by the "three fundaments" (sanji 三基), the "five happinesses" (wufu 五福) and the "ten spirits" (shijing 十精). The prognostication method of the Great Unity was based on the method of traversing the "nine palaces" (jiugong 九宮) described in the apocryphal book Yiwei qianzao du 易緯•乾鑿度.
No ancient book on the method of divination by the polestar has survived, yet Wang Ximing's book seems to assemble and describe such traditional methods. These played an important role among the many kinds of divination in imperial China. The last part of the book, in which the analysis of constellations is extended until the Jingyou reign-period 景祐 (1034-1037) of the Song era 宋 (960-1279), has been added later. The Taiyi jinjingshi jing was very popular in former times and found even entrance in the empire of the Western Xia 西夏 (1038-1227). It is included in the imperial series Siku quanshu 四庫全書 and the Siku quanshu zhenben 四庫全書珍本.