Shen (神)
Spirit — heart / upper dan tian
Shen (神) — spirit; the most refined of the three treasures. In TCM the heart is said to 'house shen' (xin cang shen) — shen is the integrating consciousness of the person, the substrate of clear thought, presence, and recognition. In Neidan, refined qi is further transformed into shen and gathered in the upper dan tian (yintang / niwan region). The full alchemical sequence — 'lian jing hua qi, lian qi hua shen, lian shen huan xu' (refine jing into qi, qi into shen, shen returning to emptiness) — is canonical in Wuzhen Pian and the broader Neidan corpus. Note the partial duality with the heart-housed shen of TCM: the same character names both the medical seat-of-consciousness and the alchemical refined substance.
Point 3 of 3 in Three Treasures (三寶) — Jing / Qi / Shen
Cross-tradition overlaps
No overlapping points are registered for this point.
Sources
Zhang Boduan, Wuzhen Pian (primary_canonical)
Wuzhen Pian, verses on refining qi into shen and returning shen toward emptiness (Pregadio 2009), is the primary alchemical source for the refined-spirit sense of this treasure.
Huangdi Neijing, Lingshu (primary_canonical)
Lingshu ch. 8 (Ben shen) identifies shen as arising through the union of essence and qi and organises the associated mind faculties, grounding the medical sense of spirit housed by the heart.