Dang, jonghae had written five books on chinese medicine, 『Hyeoljeungron』 is his most important work. He wanted to correct the fallacies of the theory of Jang(臟) and Bu(腑) by comparing with chinese and western medicine. He distinguished Bi(脾) from Cheomyuk(甛肉) by comparing the spleen with the pancreas. He recognized Stomach as the warehouse of foods, and explained that Bi took charge of digestion actually. Bi charged the function of Transportation(運化) and Blood-govering(統血) in addition to plain digestion, he wrote. Dang, jonghae regarded the metabolism of the human body as the interaction of Gi(氣), Blood (血), Water(水) and Fire(火). And he explained that Bi adjusted them. He classified Syndrome of Blood(血證) into five sorts of syndrome and presented four kinds of treatment. Especially he took a serious view of the treatment connected with Bi and Stomach. He set up the theory of Bi and Stomach(脾胃論) practically on basis of anatomy, but he didn't assorted the physiology and pathology of each organ clearly. However he proved the importance of Bi and Stomach by treating Syndrome of Blood and provided with the foundation of merging chinese and western medicine.