[Analysis of compiling date of Huang di nei jing (Huangdi's Internal Classic)].
There are Seven Medical Classics recorded in the Han shu Yi wen zhi(Bibliography in Annals of the Han Dynasty), among which the 18-volume Huang di nei jing (Huangdi's Internal Classic) is not the current edition of Ling shu (Miraculous Pivot) and Su wen(Plain Questions). The present edition of Huang di nei jing containing these two works might be merged in the Eastern Han Dynasty, benefited from the invention of Cai Lun's papermaking technique and the development of Nine needles, especially filiform needle manufacturing. Huang di nei jing was compiled on the basis of two major integrations: The first was joined by some medical experts such as Bian Que and tai yi ling (minister of imperial physicians) of the Qin State by using the language in the Warring States, contributing mainly to the theoretical system and forming its basic academic framework; The second was the second Royal book-collating activity in the Eastern Han Dynasty (100-110), which had revised the seven volumes of Chinese Medical Classics and incorporated them into two parts, Ling Shu and Su Wen, together with Bian Que's medical works and the new contents from the introductory Chapter on Nine Needles and Twelve Yuan(origin) Acupoints.