Neidan
The Furnace Is the Body
- First attested
- 8th centuryThe earliest traces of Neidan in surviving literature are the works of Tao Zhi, second half of the eighth century; Fabrizio Pregadio states flatly that no alchemical or other source suggests Neidan existed before the eighth century. Accounts placing it earlier — with Su Yuanlang (late sixth century?), Deng Yuzhi (c. 600) or the Buddhist master Huisi (515-77) — survive only in sources significantly later than the events they report, and Pregadio treats them as not historically reliable. The first clearly identifiable lineage, Zhong-Lü, named for the immortals Zhongli Quan and Lü Dongbin, develops in the ninth or tenth century; its doctrinal text is the Zhong-Lü chuandao ji and its practices are set out in the Lingbao bifa. The Wuzhen pian of Zhang Boduan, written around 1075, was made the base text of the Southern Lineage (Nanzong) in the thirteenth century; the Northern Lineage (Beizong) is the original core of Quanzhen, founded by Wang Chongyang (1113-70). On the term itself, Pregadio reports the field's view that neidan became current in the late Tang or slightly later, and that it did not at first name a branch of alchemy set against waidan.
- Claimed
- 2nd centuryasserted by Neidan commentators, and the popular literature after them, who read the Cantong qi as the first work of internal alchemy and ascribe it to Wei Boyang in the second century CE. Pregadio's 2011 study dates the text's present form no earlier than about 450, and possibly one or two centuries later still, and notes that the Cantong qi exerts no visible influence on surviving waidan texts until the seventh century.
The claim runs about 600 years ahead of the evidence.
The story that elixir deaths drove Chinese alchemy indoors is the account of waidan's own specialists, and Fabrizio Pregadio rejects it — it would have alchemists needing several centuries to notice their ingredients were fatal — tracing neidan instead to Daoist meditation on the inner gods.
Chinese internal alchemy: the elixir compounded inside the body, in the borrowed language of the laboratory.
Neidan compounds the elixir inside the practitioner, keeping the whole vocabulary of the laboratory — tripod and furnace, lead and mercury, fire phases timed by twelve hexagrams — for a process with no apparatus. The classical sequence refines essence into breath, breath into spirit, spirit back to emptiness. Fabrizio Pregadio finds no source placing neidan before the eighth century; the first identifiable lineage forms in the ninth or tenth, and Zhang Boduan wrote the Wuzhen pian around 1075. Outer alchemy did kill its patrons: Pregadio counts at least two and possibly four Tang emperors, among the poisoning cases Ho Peng Yoke and Joseph Needham drew from the dynastic histories in 1959. But the terms did not start as names for rival branches — Farzeen Baldrian-Hussein in 1989 and Isabelle Robinet in 1991 showed waidan and neidan first naming two stages inside internal practice itself.
Light
It relocates the work to the only laboratory a person always has. Zhang Boduan's sixth poem, around 1075, says everyone already owns the medicine of long life and casts it away through delusion — nothing to buy, nothing to swallow.
Shadow
The fire phases, the timing on which everything turns, are the work's most guarded part, set by a master for each disciple — nothing an outsider can audit, no book completes them. Waidan, whose vocabulary it borrowed, poisoned the patrons who swallowed its elixirs.
