The concepts of morality and health of humans are discussed from the viewpoint of Sasang medicine, as described by Je-Ma Lee in his books Donguisusebowon and Gyeokchigo. Sasang medicine suggests that human beings exist with qualities of "heavenly loom," "humanly affair," and "nature and conduct in following parts." In addition, Sasang medicine classifies people into the following four Sasang types: Tae-Yang, So-Yang, Tae-Eum, and So-Eum. This classification is based on the following traits: benevolence-righteousness-propriety-wisdom, manifestations of sorrow-anger-joy-pleasure (Seong and Jeong), and largeness and smallness of lung-spleen-liver-kidney. Human diseases are always caused by the excessive mind action of sorrow-anger-joy-pleasure. Mind action affects the body unilaterally and makes it ill. According to Sasang medicine, both good health and illness in human beings originate from morality. Therefore, realizing and acting in accordance with the right moral behavior are essential to lead a healthy life.
Keywords: Sasang medicine; health; longevity; morality.