Hú Xù 胡煦 (1655–1736), zì Cāngxiǎo 滄曉, was a Kāngxī-Yōngzhèng-period Yìjīng scholar from Guāngshān 光山 (modern Hénán 河南). He passed the jìnshì in Kāngxī rénchén 康熙壬辰 = 1712 (relatively late, at age fifty-eight) and rose through Hànlín appointments to Vice-Minister of Rites (Lǐbù shìláng 禮部侍郎).
He devoted nearly forty years to Yìxué. His original Zhōuyì hán shū 周易函書 was a vast compilation in 118 juàn comprising the main commentary on the canonical text (49 juàn), foundational essays Yuán tú 原圖 (8 juàn), Yuán guà 原卦 (3 juàn), Yuán yáo 原爻 (3 juàn), and Yuán gǔ 原古 (36 juàn) covering earlier commentators — together with separately edited supplementary works (Hán shū yuē, Yì xué xū zhī, Yì jiě biàn yì, Gōu dēng yuē zhǐ) totaling 19 more juàn.
The original 99-juàn zhèng jí (main collection) was never printed in his lifetime; the manuscript was lost when his pupil Lǐ Xuéyù 李學裕 took it for editing and died. His son Hú Jìtáng 胡季堂 reconstructed and re-edited the surviving material in three volumes:
(1) Zhōuyì hán shū yuē cún 周易函書約存 (KR1a0145) in 18 juàn — extracted essence of the yuán tú / yuán guà / yuán yáo / yuán gǔ foundational essays with the Hán shū yuē prefixed;
(2) Hán shū yuē zhù 函書約註 in 18 juàn — extracted essence of the canonical commentary;
(3) Hán shū bié jí 函書別集 in 16 juàn — the supplementary works.
Hú’s Yìxué combines selective Hàn and Sòng sources, with particular attention to the prior-heaven yuán tú 圓圖 (circular diagram) reformulated as a xún huán Tài jí tú 循環太極圖 (circulating Tài jí diagram). He proposes a number of substantively original readings — most notably treating KǎnLí as the result of QiánKūn’s mating; GènXùnZhènDuì as the result of KǎnLí’s mating; the upper-and-lower scriptures’ canonical sequence as deriving from a master pattern of trigram-mating relationships.