Ch'ien Ta-hsin 錢大昕 (T. 曉徵, 及之, H. 辛楣竹汀 ), Feb. 16, 1728-1804, Nov. 21, scholar, was a native of Chia-ting, Kiangsu. Both his grandfather, Ch'ien Wang-chiung 錢王炯 (T. 青文, 陳人, 1668-1759), and his father, Ch'ien Kuei- 錢桂發 (T. 發方, H. 方壺 1697-1775), were devoted to learning. At the early age of fifteen (sui) Ch'ien Ta-hsin became a hsiu-ts'aiand at seventeen (sui) began to teach. He taught first in the home of a family named Ku (顧) where he had access to the family library. There he studied the classics and histories, and became proficient in the new historical scholarship characterized as 考據"the search for evidence." In 1749 he was chosen to study in the Tzŭ-yang Academy (紫陽書院) at Soochow. In the following year he married Wang Shun-ying, a sister of Wang Ming-shêng [q.v.]. When Emperor Kao-tsung, on his first tour to South China (1751), granted a special examination at Nanking, Ch'ien Ta-hsin was one of the six successful competitors (see under Ch'ien Ch'ên-ch'un). Others were Wu Lang (see under Wu Ching-tzŭ) and Ch'u Yin-liang 褚寅亮 (T. 搢升 H. 鶴侶, 宗鄭 1715-1790) with whom Ch'ien Ta-hsin later studied mathematics in Peking. As a candidate for the secretaryship of the Grand Secretariat Ch'ien proceeded to the capital, early in 1752. In 1754 he passed the metropolitan and palace examinations  and became a chin-shih. A number of scholars who later achieved distinction passed the examination with him, including Chi Yün [q.v.] and his brother-in-law, Wang Ming-shêng. In the same year Ch'ien made the acquaintance of Tai Chên [q.v.] who had recently arrived in Peking. Together with Chi Yün he was ordered (1756) to assist in the compilation of the local history of Jehōl, 熱河志 Jo-ho chih, 80 chüan, completed in 1781. Both were given permission to accompany the emperor on the autumn hunting tour so that they might gather information in that locality. Ch'ien Ta-hsin became in 1757 a compiler. During these years he acquired the habit, like many other scholars who live in Peking, of frequenting Liu-li-ch'ang 琉璃廠, the famous book emporium and center for antiques. He was thus in a position to satisfy his antiquarian interest and to become a connoisseur and collector of inscriptions on metal and stone. In 1758 he became assistant secretary of the Supervisorate of Imperial Instruction. Owing to his accomplishments in mathematics he was assigned to assist the Imperial Board of Astronomy in making a map of the world (see under Ho Kuo-tsung). Several times he officiated as chief or associate examiner--in Shantung 1759, Hunan 1762, and in the Metropolitan area 1766.
After his wife's death in 1767 Ch'ien Ta-hsin was granted leave (in the winter of that year) to return home on the plea of illness. It was in that year also that his critical notes on the Twenty-two Dynastic Histories 廿二史考異 Nien-êr shih k'ao-i, completed in 1782 in 100 chüan, began to take form. In 1768 he purchased a new residence, designating his studio Ch'ien-yen t'ang 潛研堂--a name that appears in the title of many of his collected works. In the autumn of 1769 he returned to the capital and in the spring of 1772 was appointed a reader of the Hanlin Academy, with orders (1773) to supervise the study of the imperial princes and to tutor the emperor's twelfth son, Yung-chi 永？ (1752-1776). In 1774 he was director of the Honan provincial examination, after which ae became director of education in Kwangtung. Although he assumed office late in 1774 the death of his father in the summer of the next year made a necessary for him to retire for the required period of mourning. Thereafter he continued in retirement on the ground of his mother's advanced age.
In 1778 Kao Chin [q.v.], governor-general of Kiangnan, invited Ch'ien to become head of the Chung-shan Academy (鍾山書院) in Nanking where he enjoyed the friendship of such men of letters as Yüan Mei and Yen Ch'ang-ming [qq.v.]. In the spring of 1780 he went to northern Kiangsu to greet the emperor who was then making his fifth tour to South China. When Ch'ien later (1784) was on his way to meet the emperor, who was on his final tour of the South, he was stricken with paralysis. But having sufficiently recovered by 1785, he became director of the Lou-tung AcademY婁東書院 at Sungkiang, Kiangsu. In 1787 Ch'ien Wei-ch'iao (see under Ch'ien Wei-ch'êng), magistrate of Yin-hsien, Chekiang, invited him to Ningpo to direct the compilation of the local history of that district. After five months the 鄞縣志 Yin-hsien chih, in 30 chüan, was completed and was printed in the following year (1788). While thus engaged in Ningpo, Ch'ien visited the famous T'ien I Ko Library (see under Fan Mou-chu) and compiled a catalogue of its epigraphical rarities, under the title 天一閣碑目 T'ien-i-ko pei-mu, in 2 chüan. In 1789 he became director of the Tzu-yang Academy where he himself had studied some thirty years before, and remained at this post for sixteen years, until his death. During this period he taught about 2,000 students, many of whom, such as Ku Kuang-ch'i, P'an Shih-ên [qq.v.], Li Jui (see under Chiao Hsün), and T'ao Liang (see under Chu I-tsun) became famous. In the summer of 1790 he made his last journey to the capital to congratulate Emperor Kao-tsung on the latter's eightieth birthday. In 1801 Hsing Chu 邢澍 (T. 雨民, chin-shih of 1790), magistrate of Ch'ang-hsing, Chekiang, invited both Ch'ien Ta-hsin and his younger brother, Ch'ien Ta-chao [q.v.] to compile the local history of his district. While Ch'ien Ta-hsin's younger brother stayed in Ch'ang-hsing he himself divided his time between the latter place and the Academy. This local history, 長興縣志 Ch'ang-hsing hsien-chih, in 28 chüan, was completed in 1803 and was printed two years later (1805). Although ill most of the last year of his life he continued to teach, and finally died in the Academy. His name was ordered (1807) by imperial edict to be entered in the temple of local worthies.
Ch'ien Ta-hsin's complete works, Ch'ien-yen t'ang ch'üan-shu ( 全書) were first printed in 1806, and again in 1840, and 1884. The edition of 1884 consists of thirty-four items, three under classics, twenty-three under history, five under philosophy, and three under belles lettres; but eleven were not included. Under the first class  may be mentioned the 聲類 Shêng lei, in 4 chüan, a work on phonetics which was first printed in 1825, again in 1849, and later included in his complete works. But it was in the field of history that Ch'ien Ta-hsin exercised his greatest influence. In addition to the afore-mentioned Nien-êr shih k'ao i, he produced two works on the Yüan dynasty: one tracing Mongol clan and family names, the other a bibliography of the literary productions of the Yüan period. The former, in 3 chüan, was entitled 元史氏族表 Yüan-shih shih-tsu piao, and the latter, in 4 chüan, was entitled 元史藝文志 Yuan-shih i-wên chih, both completed in 1791. Conscious of the short-comings of the official dynastic history of the Yüan period, Ch'ien Ta-hsin intended to rewrite it, and the two above-mentioned works seem to be parts of that project. Chang Chih-tung [q.v.] states in his Shu-niu ta-wên that Ch'ien Ta-hsin left a draft of his Yüan history, 元史稿 Yüan-shih kao, in 100 chüan, which was never published. The Japanese bibliophile, Shimada Kan (see bibliography) affirms that a manuscript Yüan-shih kao is in existence in 28 fascicles of which the first 25 chapters are missing. During the turmoil of the Sung, Liao, Chin and Yüan dynasties the use of various reign-titles and conflicting calendars produced confusion in the writing of history. To clarify this situation Ch'ien prepared a chart, entitled 四史朔閏考 Ssŭ-shih shuo jun k'ao. Left unfinished at the time of his death, it was brought to completion by his pupil, Li Jui, and by his nephew, Ch'ien T'ung (see under Ch'ien Ta-chao). It was first printed in 1820. His corrections of Hu San-hsing's 胡三省 (身之, 1230-1287) commentary to the Tzu-chih t'ung-chien (see under Yen Yen) resulted in a work of 2 chüan, entitled 通鑑注辨正 T'ung-chien chu pien-chêng, first printed in 1792 by a pupil, Ko Chou-hsiang 戈宙襄 (T. 小蓮 1765-1827). Ch'ien also wrote five chronological biographies as follows: the biography of Hung K'uo 洪适 (T. 景伯, 1117-1184), entitled 洪文惠公年譜 Hung Wên-hui kung nien-p'u; of Hung Mai 洪邁 (T. 景廬 1123-1202), entitled 洪文敏公年譜 Hung Wên-min kung nien-p'u; of Lu Yu (see under Chao I), entitled 放翁年譜 Lu Fang-wêng nien-p'u; of Wang Ying-lin 王應麟 (T. 伯厚, 1223-1296), entitled 王伯厚年譜 Wang Po-hou nien-p'u; and of Wang Shih-chên (see under Ch'ên Chi-ju), entitled 弇州山人年譜 Yen-chou shan-jên nien-p'u.
Ch'ien Ta-hsin took special interest in recording the dates of birth and death of historical figures. The result was the well-known 疑年錄 I-nien lu, ("Record of Uncertain Dates"), which became the basis of the most important dictionary of dates in the Chinese language. This work, in 4 chüan, which recorded dates of birth and death of some 364 persons, was left incomplete at the time of Ch'ien's death, but was supplemented (hsü 續) in 1813 by a pupil named Wu Hsiu 吳修 (T. 子修, H. 思亭, 1764-1827), and published in 1818 with a few additions (補 pu) and a preface by Yao Nai [q.v.]. Further supplements to this work were compiled later as follows: Pu (補) i-nien lu, in 4 chüan, by Ch'ien Chiao, 錢椒 (T. 澥薌) with a preface by Wêng Kuang-p'ing 翁廣平 (T. 海琛, 1760-1842), dated 1838; San-hsü (三續) i-nien lu, published in 1879, in 10 chüan, by Lu Hsin-yüan [q.v.]; i-nien kêng (賡) lu, in 2 chüan, by Chang Ming-k'o 張鳴珂 (T. 公束, 1829-1908), published in 1908; Wu-hsü<> (五續 i-nien lu, in 5 chüan, by Min śr-ch'ang 閔爾昌 (T. 葆之 H. 葆之黃山). Finally all these were brought together by Chang Wei-hsiang 張惟驤 (H.- 季易) who re-edited them and printed them in 1925, with further additions, under the title I-nien lu hui-pien (彙編), "Union List of Uncertain Dates," 16 chüan--including a total of 3,928 names. As a result of his study of inscriptions on metal and stone Ch'ien Ta-hsin produced four collections of interpretative notes totaling 25 chüan, under the title 金石文跋尾 Chin-shih wen pa-wei. These were printed at various times separately before they were reedited and reprinted in his collected works in 20 chüan. A catalogue of inscriptions in his own collection, 金石文字目錄 Chin-shih wên-tzu mu-lu, 8 chüan, was edited by his son-in-law, Ch'ü<> Chung-jung 瞿中溶 (T. 萇生 H. 木夫. 1769-1842), and printed in 1805 with the assistance of another son-in-law, Hsü<> Hsi-ch'ung 許希沖 (T. 子與 H. 壽卿 original name 蔭堂 d. 1830). During his illness in 1784 Ch'ien Ta-hsin began to write his chronological autobiography, the Chu-t'ing chüshih nien-p'u 竹汀居士年譜, which he brought down to the year 1792. His great-grandson, Ch'ien Ch'ing-tsêng 錢慶曾 (T. 又沂 H. 浯溪居士, 1809-1870), completed it with additional notes of his own. A collection of Ch'ien's miscellaneous notes, entitled 十駕齋養新錄 Shih-chia chai yang-hsin lu, 20 chüan, with a supplement (餘錄) in 3 chüan, is compared by some to the famous Jih-chih lu of Ku Yen-wu [q.v.]. In the field mathematics Ch'ien produced two works,  三統術衍 San-t'ung-shu yen, 3 chüan, and San-t'ung shu ch'ien (鈐), 1 chüan. His literary collections, entitled Ch'ien-yen t'ang wên-chi (文集) and Ch'ien-yen t'ang shih (詩)-chi, comprise 50 chüan of prose and 20 chüan of verse. Except for certain titles published separately or in collectanea, all the afore-mentioned works can be found in the 1884 edition of Ch'ien's collected works.
Ch'ien Ta-hsin had two sons, Ch'ien Tung-pi 錢東壁 (T. 星伯，飲石 H. 夢漁 1766-1818) and Ch'ien Tung-shu 錢東塾 (T. 學仲 H. 子臬，學韓，膠田，石橋，東橋，石丈 1768-1833). Both were ardent students, and the latter was also a painter and calligrapher. Ch'ien Ta-hsin himself achieved a moderate reputation as a calligrapher and a painter.
[ 3/128/la; 19/ 丁上/21b; 20/3/00 (portrait); Chronological Autobiography;錢竹汀先生行述 Ch'ien Chu-t'ing hsien-shêng hsing-shu by his sons; Chia-ting hsien chih (1880) 16/51b, 19/31b; Shimada Kan 島田翰, 古文舊書考 Ku-wên chiu-shu k'ao; T'oung Pao (1931) p. 379, 027-28) pp. 64-81, "Les Yi Nien Lou".]