1. The physiological functions of the five organs and their mutual relations
This theory classifies the viscera of the organism by explaining their physiological functions according to the particularities of each element.
– The wood grows upwards and expands outwards. The liver prefers expansion, hates inhibition, and one of its functions is drainage and evacuation.
– Fire flames and ascends upwards. Heart yang has the function of warming.
– The earth produces and transforms. The spleen transforms the grains (food) and transports the nutrients to nourish the gut-organs and the 4 limbs. This being the principle of blood-energy formation.
– The metal purifies and distributes. The lung has distribution as one of its functions. Its energy must descend downwards.
– Water moistens and filters downwards. The kidney reserves the essence and controls the liquids.
To the characteristics or particularities of each element (seen above) we will add some of the relationships according to the cycle of generation:
– Wood produces fire: the liver is the mother of the heart. One of the functions of the liver is to reserve the blood and nourish the blood of the heart, the blood in its turn houses the mind if the liver blood is weak the heart (Shen) will be unstable.
On the other hand the liver’s function of drainage and evacuation seconds the heart yang.
– Fire produces the earth: the heart is the mother of the spleen. One of the functions of the heart is to propel the blood, thus supporting the spleen in its function of transporting nutrients throughout the organism (the yang of the heart).
The heart’s yang warms the spleen yang, supporting it in its function of transport and transformation and in its function of controlling the blood.
– Earth produces metal: the spleen is the mother of the lung. The spleen Qi supplies the Qi of the food to the lung where it mixes with the air and thus forms the Qi of gathering.
The spleen transforms liquids to prevent the accumulation of Tan (mucus) in the lung.
– Metal produces water: the lung is the mother of the kidneys. The Lung Qi descends to meet the Kidney Qi. Also the lung sends fluids to the kidney (the lung thus protects the kidney yin).
– Water produces wood: the kidney is the mother of the liver. Kidney yin nourishes blood and liver yin.
Some relationships according to the cycle of domination (control-inhibition):
– Wood dominates earth: liver helps the stomach to decompose and ripen food and helps the spleen to transform and transport it. If the function of the liver
(drainage and evacuation) is not correct, the domination becomes aggression of the liver to the spleen-stomach.
– Fire dominates metal: the heart governs blood and the lung governs Qi, Qi and blood help and nourish each other (Qi drives blood, blood nourishes Qi).
Qi). On the other hand heart yang restricts the purifying function of the lung (this function of the lung is of a cold nature), to avoid its excess.
If the heart yang is insufficient, the lung will become too cold and will not distribute the liquid, which will accumulate in the form of mucus (tan-yin).
– Earth dominates water: both the spleen and kidney transform organic fluids. The spleen’s function of transporting and transforming liquids is essential for the kidney’s function of transformation.
the kidney’s function of transformation and excretion.
– Metal dominates wood: the lung sends the Qi downwards, the liver transports it upwards. If the lung is weakened and cannot descend, the liver Qi can
ascend too much (thus producing an excess of liver yang).
– Water dominates fire: the two assist and help each other, the essence-preserving kidney prevents excess fire from the heart.