Yishu gouyin tu 易數鉤隱圖

Yishu gouyin tu 易數鉤隱圖 "Charts for probing the hidden meaning of numbers [and symbols/emblems] in the Book of Changes" is a numerological-emblemological (Fung 1952: 452) commentary on the Classic Yijing 易經 "Book of Changes" compiled by Liu Mu 劉牧 (1011-1064), courtesy name Xianzhi 先之, style Zhangmin Xiansheng 長民先生, from Quzhou 衢州 (today's Xuqian 衢縣, Zhejiang).

His interpretations quite probably go back to the propositions of the Daoist master Chen Tuan 陳摶 (871-989) and Zhong Fang 種放 (955-1015), even if his teacher was Fan Echang 范諤昌. The book is mentioned in the bibliographical chapter (202-209 Yiwen zhi 藝文志) of the history book Songshi 宋史 and in the catalogue Zhongxing guange shumu 中興館閣書目 as a text with a length of 1 juan, but the bibliographies Tongzhi yiwen lüe 通志藝文略, Mige cangshu mulu 秘閣藏書目錄 and Junzhai dushu zhi 郡齋讀書志 speak of an arrangement of 3 juan, which corresponds with that in the imperial series Siku quanshu 四庫全書 and the Daoist canon Zhengtong Daozang 正統道藏.

Liu's book explains various statements of the Yijing with the help of diagrams, in which the figures of the eight hexagrams (guaxiang 卦象) play the central role. The author holds that "wise men" (shengren 聖人) once invented the hexagrams (gua 卦) to express and "observe" the emblems or symbols (guan xiang 觀象) which worked as primordial archetypes of the really existing objects (xing 形 "shapes"). The archetypes themselves were products of numbers, for example, the Utmost Extreme (taiji 太極) as a unity (one), which split into the two energies or potentials (liang yi 兩儀) Yin and Yang 陰陽, out of which the four seasons emerged which in turn produced the eight trigrams. Out of these, the ten thousand beings (wanwu 萬物) emerged.

The whole book includes no less than 55 figures or charts which illustrate the explanations of the text. The first 16 figures are related to the Utmost Extreme (Taiji), the two energies (Yin and Yang), the "four phenomena or emblems" (sixiang 四象, i.e. the four seasons), the eight trigrams, and Heaven and Earth (tian di 天地). Figures 17-48 describe the constitutions and constellations of Yin and Yang, Qian and Kun 乾坤 and the rest of the trigrams, the Five Agents (wuxing 五行) and the "three skilled ones" (sancai 三才, i.e. Heaven, Earth, and Man). Figures 49-54 represent the Yellow River Chart (Hetu 河圖) and the Inscription of the River Luo (Luoshu 洛書), and the last figure the transformation of the ten days (shi ri 十日) and the Five Agents.

An appendix to the book called Longtu guishu lun 龍圖龜書論 "Discussion of the dragon chart and the tortoise inscription" provides further explanations to Hetu and Luoshu theory, but this part of the book was harshly criticized by later scholars because in many points it run contrary to the commonly accepted statements of Ruan Yi's 阮逸 (jinshi degree 1027) Guan Lang yizhuan 關朗易傳 and Cai Yuanding's 蔡元定 (1135-1198) Yixue qimeng zhu 易學啟蒙注.

The text is also found in the series Tongzhitang jingjie 通志堂經解.