Yen Jo-chü<> 閻若璩 (T. 百詩 H. 潛丘), 10 11, 1636-1704, July 9, classicist, mathematician, and geographer, was born in Huai-an, Kiangsu of a family known for its literary tradition. His grandfather, Yen Shih-k'o 閻世科 (T. 伯登 H. 磻楚, 龍門, 1570-1642), was a chin-shih of 1604 who rose to be secretary to an  intendant in Liaotung (1617-18). His father, Yen Hsiu-ling 閻修齡 (T. 再彭 H. 牛叟 1617-1687), earned a reputation as a literary man and left collections of prose and verse. His mother, née Ting Hsien-yao 丁仙窈 (T. 少善, 1618-1674), is said to have been an accomplished woman. As a boy, Yen Jo-chü<> was not particularly brilliant, but at the age of fifteen (sui) he began to show unusual aptitude, and his progress gradually evoked the admiration of local scholars. At the age of twenty-eight (sui) he went to Taiyuan, Shansi, to compete in the public examinations and became a hsiu-ts'ai (1663). Officially he was a resident of Taiyuan, the birthplace of his ancestors, although his family no longer actually lived there. When Ku Yen-wu[q.v.], the leading scholar of his day, visited Taiyuan in 1672 he consulted Yen about his well-known work, the Jih-chih lu. Yen made several corrections in it which Ku willingly accepted. Having failed in successive examinations for the chü-jên degree, Yen was recommended (1678) to be a candidate for the special examination known as po-hsüeh hung-tz'ŭ, held in 1679, but failed. His reputation, however, did not suffer on that account, for at this time many of the most original minds were unsuccessful in the formal examinations. He so impressed his contemporaries that during his sojourn in Peking he was asked to become the personal literary adviser of Hsü<> Ch'ien-hsüeh[q.v.]. In the years 1682-83 he made a journey to Fukien. In 1686, Hsü<> was appointed an assistant director-general to edit the topographical work, Ta-Ch'ing i-t'ung chih, and was raised to a director-general in 1687. From 1686 Yen acted as his leading adviser and contributor, and when Hsü<> returned in 1690 to his native place, Yen accompanied him. For two years he assisted in the compilation of this work in the editorial office which Hsü<> established privately near Soochow. After Hsü<> was deprived of his rank, and the editorial office was closed, Yen retired to Huai-an (1692). He lived long enough to be recognized as one of the greatest classicists of his day and was regarded by Wang Chung [q.v.] as one of the six great scholars of the Ch'ing period-a conclusion now generally accepted. His erudition attracted the attention of Margun, the second Prince An (see under Yolo), who invited him to his mansion in Peking early in 1704 and received him with great deference. [ Many sources mistakenly assert that the invitation came from Yin-chên; q.v.]. Seriously ill at this time, he died in Peking soon after.
The life of Yen Jo-chü<> was unusually quiet and uneventful, but it was full of great literary achievements. Most of his works-more than ten in number-are in the field of classical study and historical geography. His most important study, which raised him to the front rank as a critical historian, is his 尚書古文疏證 Shang-shu ku-wên shu-chêng ("Inquiry into the Authenticity of the Shang-shu in Ancient Characters"), 8 chüan, first printed in 1745 but seen by some in manuscript earlier. The so-called ancient text of the Shang-shu, or Shu-ching (i.e. Classic of History), was for a long time one of the most baffling of textual problems. At the beginning of the Han Dynasty, or early in the second century B. C., only twenty-nine chapters of this work were preserved. Later, in the reign of Emperor Ching (156-140 B. C.)-according to Wang Ch'ung 王充 (T. 仲任, b. 27 A. D.) an ancient text was discovered which was written in a much more archaic style of handwriting and contained sixteen more chapters than the version then current. Owing to this difference in script the two versions are distinguished as the ku-wên or "ancient" text, and the chin-wên 今文 or "modern" text. K'ung An-kuo 孔安國, a descendant of Confucius and a professor in the Imperial Academy in the reign of Emperor Wu (140-86 B. C.), was--according to Ssŭ-ma Ch'ien 司馬遷 (T. 子長, 145-ca. 87 B. C.)--the first person to make a study of the ancient classical texts, including the Classic of History. He was followed by many prominent scholars like Chia K'uei 賈逵 (T. 景伯, 30-101 A. D.), Ma Yung 馬融 (T. 季長 79-166 A. D.), Chêng Hsüan (see under Chang Êr-ch'i) and others. This ancient text of the History was probably lost, however, during the troubled years following the fall of the Han Dynasty. At least certain great scholars of the Western Chin period (265-317 A. D.), like Tu Yü<> (see under Ting Yen), Kuo P'u (see under Ku Kuang-ch'i) and others, appear not to have seen it. Nevertheless, suddenly, in the period 317-322 A. D., Mei Tse 梅賾 (T.) presented to Emperor Yüan an alleged "ancient text" of the Classic of History with a commentary by K'ung An-kuo. This text came into general use and later was the one used officially in the literary examinations-displacing the one now regarded as authoritative. Even the great commentator, K'ung Ying-ta 孔穎達 (T. 仲達, 574-648 A. D.), descendant of Confucius in the thirty-second degree, took it to be genuine.
In the Sung Dynasty scholars like Wu Yü 吳棫 (T. 才老, chin-shih of 1124), Chu Hsi (see under Hu Wei), and others, cast doubts upon the authenticity of the fourth century text; and in the year 1543 Mei Tsu (see under Sun Hsing-yen) published his ku-wên Shang-shu k'ao-i ("A Study of Discrepancies in the Shuching in Ancient Characters"). But, even so, the authenticity of a text which had circulated so long was not generally questioned. By the time Yen Jo-chü<> was twenty years of age he began to doubt its authenticity and devoted the next thirty years to an exhaustive study of the problen). The result is the above-mentioned Shang-shu ku-wên shu-chêng which, by convincing evidence and judicious arguments, proved beyond doubt that the "ancient text", which had circulated for a millenium, is a forgery. Although some scholars took issuewith Yen's conclusions ksee under Mao Ch'i-ling), most of the adherents of the School of Han Learning (see under Ku Yen-wu) saw no reason to doubt them. The importance of Yen's discovery to Chinese historical criticism can scarcely be exaggerated. Not only was a long-venerated Classic taken down from its exalted position, but the way was opened for a critical examination of any work of antiquity--no matter how sacred.
Equally daring, and scarcely less revolutionary, was Yen's examination of the authorship of the Ta-hsüeh, or Great Learning--originally a chapter in the Record of Rites (Li-chi) and now one of the Four Books. He pointed out that the attribution of the work, by Sung scholars, to Tsêng Shên 曾參 (i.e. Tsêng-tzu, b. 505 B. C.) and his disciples was without foundation. Yen's argument was so conclusive that the traditional belief was shaken.
Yen Jo-chü<> had a vivid sense of chronology, as his Shang-shu ku-wên shu-chêng and his 孟子生卒年考 Mêng-tzu shêng-tsu-nien k'ao ("An Investigation of the Birth and Death Dates of Mencius") indicate. The last-named work was printed a few years before his death. He was also a specialist in historical geography, a knowledge of which he regarded as indispensable to an understanding of classical works. His 四書釋地 Ssŭ-shu shih-ti ("Analysis of the Place Names in the Four Books"), 6 chüan, is a valuable contribution both to geographical and classical scholarship, and has been supplemented at carious times. It was first printed in serial form about the year 1696, and was reprinted as a whole in 1787. Yen Jo-chü<> also left a collection of miscellaneous notes, entitled 潛邱劄記 Ch'ien-ch'iu cha-chi, 6 chüan ; which was printed by his grandson, Yen Hsüeh-lin 閻學林 (T. 信藪). Appended to it is the literary collection, 左汾近稿 Tso fên chin-kao, of his eldest son, Yen Yung 閻詠 (T. 復申, original ming 詒樸 T. 元木 H. 左汾, chin-shih of 1709). A chronological hiography of Yen Jo-chü<> i, referred to in the biography of Chang Mu [q.v.] in this dictionary. A set of Yen's miscellaneous stmlies appear in various ts'ung-shu.
[ I1487/8.v; 2/68/17a; 3/k15/7a; 4/131/8a; 7/3:%la; Li Tsung-fang, 聞妙香室文集 Wên miao-hsiang shih wên-chi (1835) 12/l; Yen Jo-chū<> hsien-shêng nien-p'u (see under Chang Mu), Ssŭ-k'u, passim; Ch'ien Ta-hsin [q.v.]Ch'ien Yen-t'ang ch'üan-shu (wên-chi, Changsha, 1884), 38/5a-11b; Ting Kuo-chün, 荷香館瑣言 Ho-hsiang kuan so-yen, hsia 20a; Chao-lien [q.v.], Hsiao-t'ing tsa-lu 5/37a.]
S. H. CH'I