Qín Yuèrén 秦越人, conventionally known as Biǎn Què 扁鵲, the legendary physician of the Warring States period. The name “Biǎn Què” originally belonged to a Yellow-Emperor-period physician; it was applied to Qín as an honorific because his abilities were considered comparable. He is also known as the “Lú Physician” (Lú yī 盧醫), from his settlement in the state of Lú 盧. His historicity is uncertain — Sīmǎ Qiān’s Shǐ jì 史記 biography (j. 105) attributes to him miraculous diagnostic powers (X-ray-like vision through the abdomen, granted by his teacher Chángsāng Jūn 長桑君 via an “upper-pool water” elixir) — but his name became the canonical authorial attribution for the Nán jīng 八十一難經 (KR3e0003, KR3e0004, KR3e0007, KR3e0008), the Warring-States to early-Hàn medical text setting out eighty-one points of difficulty in the Huángdì nèijīng. Modern scholarship treats the Nán jīng as a late-Warring-States to early-Hàn anonymous compilation pseudepigraphically attributed to Biǎn Què; the Hàn Yìwén zhì makes no mention of it, but the Suí zhì is the first to record it. The Wú Imperial Physician Lǚ Guǎng 呂廣 wrote the earliest known commentary, indicating that the work was already in circulation before the Three Kingdoms.