Zhēn Déxiù 眞德秀 (1178–1235), zì originally Jǐngyuán 景元, later Xīyuán 希元, hào Xīshān xiānsheng 西山先生, posthumously Wénzhōng 文忠, was the leading mid-Southern-Sòng Lǐxué statesman and the principal channel of the ZhūXī tradition’s institutional consolidation in the post-Qìngyuán dǎngjìn generation. Native of Pǔchéng 浦城 (Fújiàn). Jìnshì of Qìngyuán 5 (1199); bóxué hóngcí in 1205. Held a sequence of senior court and provincial posts, rising under Lǐzōng 理宗 to Cānzhī zhèngshì 參知政事 in 1235, the year of his death. Personal disciple of Zhān Tǐrén 詹體仁 (a direct Zhū Xī student); his learning is therefore second-generation post-Zhū. With Wèi Liǎowēng 魏了翁, he is one of the ÈrWèi of the post-dǎngjìn recovery. His major works include the Dàxué yǎnyì 大學衍義 (KR3a0058 — the master imperial-pedagogical Dàxué commentary, in 43 juan), the Xīshān dúshū jì 西山讀書記 (KR3a0059, his comprehensive Lǐxué notebook in 40 juan), the Xīn jīng 心經 (KR3a0060, 1 juan, the foundational xīnxìng compilation), the Zhèng jīng 政經 (KR3a0061, 1 juan, on government), the Wénzhāng zhèng zōng 文章正宗 (the canonical literary anthology), and the substantial Xīshān wénjí 西山文集. The Dàxué yǎnyì in particular became the standard imperial-instructional text for the YuánMíngQīng courts. Biography: Sòng shǐ j. 437 (Rúlín zhuàn). CBDB id 10258, dates 1178–1235.
(Note: the simplified-character form 真 and the variant 眞 — both used for the personal name — are interchangeable; the catalog meta and SKQS prefer 眞.)