Wèi Zhēng 魏徵
Zì Xuánchéng 玄成; posthumous title Wénzhēn 文貞. Native of Jùlù 鉅鹿 (in modern Héběi). CBDB id 15610; lifedates 580–643 (per CBDB and catalog meta).
The most famous remonstrating minister of the early Tang. Originally a follower of Lǐ Mì 李密 in the late-Suí rebellions, then of the Crown Prince Lǐ Jiànchéng 李建成 of the new Tang court. After the Xuánwǔmén zhī biàn 玄武門之變 of 626 in which Lǐ Shìmín killed his brother Jiànchéng to seize the throne, Wèi Zhēng was spared and brought into Tàizōng’s inner circle on the explicit ground of his outspoken loyalty. Held Jiànyì dàifu 諫議大夫 from 627, Mìshū jiàn 秘書監 from 629, Ménxià shìláng 門下侍郎 / Shìzhōng 侍中 from 633 — equivalent to chief ministership — until his death in 643. Enfeoffed as Zhèngguó gōng 鄭國公.
His memorials of remonstration to Tang Tàizōng — most famously the Shí jiàn 十諫 (Ten Things to Be Watched) of 638 — are preserved in his Wèi Zhènggōng wén jí and partly anthologised in the Zhēnguān zhèngyào 貞觀政要. They are the canonical model of “zhí jiàn” 直諫 (forthright remonstration) in Chinese political literature, and Tàizōng’s most-cited utterance after Wèi’s death — “with bronze as a mirror you may set right your dress; with the past as a mirror you may know rise and fall; with people as a mirror you may know gain and loss; I have lost a mirror” 以銅為鑒…魏徵歿，朕亡一鑒矣 — is the canonical statement of the early-Tang theory of jiànjiè 鑒戒 (the past as warning).
Scholarly contributions: chief editor of the Suí shū (KR2a0023), 85 juǎn, presented in Zhēnguān 10 (636); supervising editor (jiānxiū) for the Liáng shū (KR2a0018), Chén shū (KR2a0019), and Běi Qí shū (KR2a0021); chief compiler of the Wǔdài shǐ zhì 五代史志 (the ten zhì ultimately attached to the Suí shū, presented under Tang Gāozōng in 656). Author of the Lèi lǐ 類禮 in 20 juǎn (a Confucian-canonical compilation, lost) and the Cìzhě zhī liáng 次者之良 essays.
His biographies are in Jiù Tángshū 71 and Xīn Tángshū 97 (KR2a0026, KR2a0027).