Jiāo Yánshòu 焦延壽 (also known as Jiāo Gàn 焦贛)
Style name Yánshòu 延壽 (with personal name Gàn 贛 / Jiāo Gàn). Native of Liáng 梁 (in modern Hénán). Active during the reigns of Wǔdì and Zhāodì (mid-Western Hàn, mid-1st century BCE). Birth and death years not securely recorded.
A foundational figure in the Hàn-period Yìjīng numerical-divinatory tradition. Originally a county clerk; promoted to Xiǎohuáng lìng (Magistrate of Xiǎohuáng) under Zhāodì by jǔxiào lián recommendation. The famous Yìjīng commentator Jīng Fáng 京房 (KR3g0030) was his student; the Hànshū records Jīng Fáng’s biographical details including the Jiāo Yánshòu transmission, providing the principal historical evidence for Jiāo Yánshòu’s existence and intellectual position.
Jiāo Yánshòu’s distinctive contribution: he created the guàqì zhírì 卦氣值日 (hexagram-pneuma duty-day) tradition — a Yìjīng-divinatory system in which each hexagram is assigned a calendar-day position, with auspicious-or-inauspicious determinations derived from the day-on-which-divination-falls. This methodology became the foundation of all subsequent xiàngshù (image-and-number) Yì-tradition divinatory practice, transmitted through Jīng Fáng to the Hàn imperial court and through subsequent commentators down to the Sòng-Yuán period.
His principal work is the KR3g0029 Jiāoshì Yìlín 焦氏易林 in 16 juàn — a divinatory-poetry compendium containing 4,096 (= 64 × 64) four-character-line yáocí (oracular verses), one for each combination of an “original” hexagram and a “transformed” hexagram. The work’s compositional ambition is monumental: each entry presents a unique cosmological-cum-ethical situation in compact verse-form, with the entire 4,096-entry set serving as a divinatory reference. The work is also a rich source for the study of Hàn-period folk-cosmology, language, and culture (its verse-language preserves vocabulary and idioms not always documented elsewhere).
A separate work, the Yìlín biànzhàn 易林變占 in 16 juàn, is recorded in the Suí Jīngjí zhì but is now lost.