Five Phases (Wuxing) at the Five Zang Organs

Xīn (心) — the heart, paired with the fire phase. The Suwen calls the heart 'the sovereign of the five zang' (Suwen 8): it governs the blood and the vessels, houses the shen (consciousness, mental clarity, integrative awareness), and corresponds to the season of summer, the southern direction, the colour red, the bitter taste, and the emotion of joy. In Lingshu 8 the heart-shen pairing is given as the principal axis around which the other zang-mind pairings (liver-hun, lung-po, spleen-yi, kidney-zhi) are organised. Clinically, heart pathology in TCM presents either as deficiency of the shen (anxious agitation, palpitations, insomnia, scattered speech) or as obstruction of the heart's vessels. The heart is the only zang for which the Neijing forbids direct needling — Suwen prohibits puncture at the proper heart, treating instead via the pericardium meridian.

Fèi (肺) — the lungs, paired with the metal phase. The Suwen calls the lungs 'the canopy of the zang' (huá gài, 華蓋), positioned highest in the body cavity above all the other organs. They govern qi (the breath as the body's qi-substrate), descend the qi to the kidneys for storage, and rule the skin and body-hair as the boundary of the body. They correspond to autumn, the western direction, the colour white, the pungent taste, and the emotion of grief. Lingshu 8 pairs the lungs with the po (魄) — the corporeal soul, the seven 'animal-vital' faculties that animate the body without consciousness and depart with the breath at death. We render the lungs as a single bilateral point on the anatomical-right side at lung-region height (x=0.40, y=0.23, with y interpreted as the upper-thoracic level beneath the clavicles), with the understanding that the canonical zang is paired (two lungs, both belonging to the metal phase).

Gān (肝) — the liver, paired with the wood phase. The Suwen calls the liver 'the general' (jiāng jūn, 將軍), responsible for the strategising and free-flowing direction of qi throughout the body. It stores blood, governs the smooth flow of qi (so that constraint of the liver-qi produces stagnation, the most common pattern in TCM internal medicine), and rules the sinews and the eyes. It corresponds to spring, the eastern direction, the colour green, the sour taste, and the emotion of anger. Lingshu 8 pairs the liver with the hun (魂) — the ethereal soul, that which travels in dreams and survives death to return to the ancestors. The liver-hun is therefore both the organ of strategic planning in waking life and the substrate of the life that continues after the body dies. We render the rendered point at the anatomical-right liver-region landmark (x=0.42, y=0.36).

Pí (脾) — the spleen, paired with the earth phase. The Suwen places the spleen at the centre of the five zang, corresponding to the centre direction (the fifth direction, central to the four cardinal points), to late summer, to the colour yellow, and to the sweet taste. The spleen governs the transformation and transportation of food essence (yùn huà, 運化) — it is the principal digestive organ in TCM physiology, responsible for raising the clear qi extracted from food and sending it upward to the lungs and heart. Lingshu 8 pairs the spleen with the yi (意) — intention, the cognitive faculty of focused attention and intellectual application. The yi is what allows mental work to be sustained over time, and chronic over-thinking is canonically said to deplete the spleen. We render the rendered point at the anatomical-left upper-abdominal landmark (x=0.58, y=0.36); note that the TCM spleen is a functional system that includes but is not limited to the anatomical spleen, and substantial overlap exists with the pancreas in modern correlations.

Shèn (腎) — the kidneys, paired with the water phase and treated by the Neijing as the root of life (xian tian zhi ben, 先天之本). They store the jing (essence), govern reproduction, growth, and the basal warmth of the body, and rule the bones, marrow, and the lower-back lumbar region. They correspond to winter, the northern direction, the colour black, the salty taste, and the emotion of fear. Lingshu 8 pairs the kidneys with the zhi (志) — will, determination, the steady undercurrent of motivation that survives the wavering of mind and feeling. The kidney-zhi pairing is the substrate of the long-term endurance required for any sustained discipline. We render the rendered point at the anatomical-right kidney landmark (x=0.42, y=0.42), with the canonical TCM understanding that the kidneys are a paired bilateral organ-system; the Neidan tradition further distinguishes left kidney (water proper) from right kidney (ming men, the gate of life, the residence of the yang root) — a distinction not rendered here at the schematic level.