Spleen and Stomach: Central Transportation, Transformation, and Distribution from the Great Granary
The South gives rise to Heat; Heat gives rise to Fire; Fire gives rise to bitterness; bitterness gives rise to the Heart. The Inner Canon says: “That which takes responsibility for things is called the Heart. What the Heart remembers is called intention; what intention retains is called will; what changes within will is called thought; what thought reaches toward afar is called deliberation; and what deliberation uses to deal with affairs is called wisdom.” Thus the Heart is “the official of the sovereign, from which spirit-illumination emerges.”
All Blood belongs to the Heart, and it stores the shen. Its trigram is Li; in the body it corresponds to the vessels; its color is red; its tone is Zhi; its voice is laughter; its emotion is joy; its movement-change is worry; its orifices are the ear and tongue; its flavor is bitter. Its fluid is sweat, its external luster the complexion, its odor scorched, its number seven, its grain broomcorn millet, its creature the feathered class, its fruit apricot, and its vegetable Chinese chive. The Heart is paired with the Small Intestine and is controlled by the Kidney. It dislikes Heat; sorrow, worry, and excessive thought can injure it. Heart disease may cause pain in the chest, fullness of the supporting flanks, pain beneath the ribs, pain of the chest and back or between the shoulder blades, and pain along the inner arms. In deficiency, pain may draw between the chest, abdomen, large flanks, and lower back.
Small Intestine
Section titled “Small Intestine”The Small Intestine is “the official of receiving and containing, from which transformation of substances emerges.” It belongs to Fire and is the fu paired with the Heart. Tang Zonghai explains that it connects above with the Stomach; everything received by the Stomach is passed into the Small Intestine. The Small Intestine is connected throughout with membranous tissues containing fine vessels. Bitter bile from the Gallbladder and sweet fluids associated with the Spleen enter and participate in digestion. The refined juices produced from food pass through the membrane network and reach the zang, hence “transformation of substances emerges from it.”
The route by which the Small Intestine communicates with the Heart is described as fine vessels in this membranous network ascending through the diaphragm to the pericardial network and thereby communicating with the Heart. Food is transformed into fluid in the Small Intestine, leaves through the connected network, ascends to support the Heart, and contributes to the generation of Blood.
If Heat from the Heart is transmitted to the Small Intestine, transformation may fail, producing dysenteric or urinary difficulty. Zhang Zhongjing is quoted as saying that Cold in the Small Intestine may cause heaviness below and blood in the stool, while Heat may produce hemorrhoids. A classical passage states that Small-Intestine disease can cause lower-abdominal pain with pulling pain through the lower back, spine, and testicular region.