Mid-Táng nèidān 內丹 / waidan 外丹 alchemist (d. 825), known as Táo zhēnrén 陶真人 (“the Perfected Master Táo”). Author of Huánjīn shù 還金術 (DZ 922), an alchemical treatise frequently quoted by Sòng-period inner-alchemy commentators including those of DZ 259 Táo zhēnrén nèidān fù, DZ 261 Jīndān fù, and DZ 266 Jīnyè huándān bǎiwèn jué. The attribution to Táo Zhí of the Nèidān fù 內丹賦 (“Ode on the Inner Elixir”) preserved at DZ 259 is, however, disputed: the anonymous commentary cites Táo’s Huánjīn shù in the third person (“Mr. Táo says…”), suggesting the commentary was not by Táo himself; on Schipper & Verellen’s analysis the commentary post-dates Táo’s death and may belong to the Five Dynasties (907–960). Táo’s Huánjīn shù and the present fù both express a transitional position between Táng waidan alchemy and the emerging Sòng nèidān synthesis: lead and mercury remain the only legitimate “ingredients,” but they are increasingly read as inner-body symbols rather than as physical metals. No CBDB record found; lifedates derive from the standard scholarly consensus following Baldrian-Hussein’s TC entries.