Yao Nai 姚鼐 (1731-1815), courtesy name Jichuan 姬傳 or Menghu 夢榖, style Xibaoxuan 惜抱軒, was a writer, publisher and philosopher of the mid-Qing period 清 (1644-1911). He hailed from Tongcheng 桐城, Anhui 安徽, and obtained the jinshi degree in 1763. He was xxx 刑部郎中 and provincial examinational 鄉試考官 in Shandong and Hunan. 會試同考官. 記名御史，四庫全書館纂修官 All his life, he supported several academies, like the Meihua Shuyuan 梅花書院 in Yangzhou 揚州, the Ziyang Shuyuan 紫陽書院 in Huizhou 徽州, the Zhongshan Shuyuan 鐘山書院 in Jiangning 江寧 and the Jingfu Shuyuan 敬敷書院 in Anqing 安慶.
The writer Yao Nai was a disciple of Fang Bao 方苞 (1668-1749), Liu Dakui 劉大櫆 (1698—1779 or 1780) and Yao Fan 姚范 (1702—1771), who advocated the use of the unembellished, simple and clear style of “ancient literature” (guwen 古文). These persons were the oldest representatives of the Tongcheng School of literature (Tongchengpai 桐城派).
Yao Nai was on the one hand an adherent of Neo-Confucianism in the tradition of the brothers Cheng and Zhu Xi 朱熹 (1130-1200) from the Song period 宋 (960-1279), but on the other hand he had to answer the contemporary trend of going back to Han-period 漢 (206 BCE-220 CE) texts with the tool of critical analysis. He therefore decided to combine the concepts of Neo-Confucianism (lixue 理學) – with the universal principle (li 理) at its core – with those of the critical school (kaozhengxue 考證學, see Qian-Jia School). He even went a step further and brought literary theory into the field and merged the aspect of the righteousness of the universal principle (yili 義理) with critical analysis and collation (kaoju 考據), and textual composition (cizhang 辭章). He concluded that a scholar had to rely on all three aspects, and that scholarly sound articles and excellent literature could not miss one of the three factors. Yet of the three, the universal principle stood in the centre as the "substance” (bi yili wei zhi 必義理為質), while the two others were (supportive, xiangji 相濟) additions (wenci you suo fu, kaoju you suo gui 文辭有所附，考據有所歸). However, Yao himself cannot be rated as a master in collation, nor was he remarkable thinker of Neo-Confucianism.
His theoretical strengths were laying in the composition of texts (wenzhang zuofa 文章作法) and the selection of styles (fengge 風格). In the field of literary theory, Yao Nai created the concept of the interplay of “the softness Yin” (yin rou 陰柔) with the “hardness of Yang” (yang gang 陽剛). The concept is derived from natural philosophy (see Yin-Yang School) and had found entrance into Neo-Confucianism, but the zero-sum game between the two styles of Yin and Yang can be compared with his tripartite concept of the universal principle, collation, and textual composition, as well. No good text was possible without a well-balanced interplay of Yin and Yang, which were simultaneously opposed to each other, and also supporting each other and gradually transgressing into the other form (xiang fu xiang cheng 相輔相成).
In a similar way, Yao Nai stressed that the search for excellent literature had to pass a stage of “crudeness” before coming into the age of matured fineness. He adopted the theory of Liu Daikui by explaining that the pure structure of poems as well as aspects of shape and sound were the “crude” aspect of literature (ge lü sheng se zhe, wen zhi cu ye 格律聲色文之粗也), while the refined aspect was found in “spirit, the principle, energy and taste” (shen li qi wei zhe, wen zhi jing ye 神理氣味者，文之精也).
This literary concept could transposed to the philosophical sphere as well, because the philosophy of the Han period were the necessary foundations, while perfection could only be achieved by the study of the Song-period masters of Neo-Confucianism.
The most visible character of good literature was if a writer showed his talent by exerting his skills or methods (yun qi fa zhe cai ye 運其法者才也), while the utmost exhaustion of talent was his skill (ji qi cai zhe fa ye 極其才者法也). In antiquity, the age of good writing, writers hd have certain fixed methods (you yiding zhi fa 有一定之法), and also not predetermined skills (you wuding zhi fa 有無定之法). The former were used to create strict arrangements (yan zheng 嚴整), and the latter to allow changes in all directions (zongheng bianhua 縱橫變化). The two kinds of methods therefore supported each other, and not obstruct each other.
The consequence of these tenets was for Yao Nai that works and author had to conjoin. One would not become a good poet by one’s own will (bu zi ming wei shiren 不自命為詩人), but because of the energy found in a loyal attitude, a high-standing composure of simplicity, nourishment of moral principles, and understanding of matters of statecraft.
The collected writings of Yao Nai are called Xibaoxuan quanji 惜抱軒全集. Among his writings are quite a few commentaries on classical books like Zuozhuan buzhu 左傳補注, Gongyangzhuan buzhu 公羊傳補注, Guliangzhuan buzhu 榖梁傳補注, Jiujingshuo 九經說, Laozi zhangyi 老子章義, Zhuangzi zhangyi 莊子章義 or Guoyu buzhu 國語補注. He also wrote a text on calligraphy, Fatie tiba 法帖題跋. Not included in this collection are Yao’s anthologies Gu wenci leizuan 古文辭類纂 and Wu-qiyan jinti shichao 五七言今體詩鈔.