Sasang typology

The Sasang typology (Hangul: 사상의학. Hanja: 四象醫學) is a classification scheme in Traditional Korean medicine. It was systematized by Lee Je-ma in his book Longevity and Life Preservation in Eastern Medicine (東醫壽世保元, 동의수세보원) in 1894. It divides people in four types based on their biopsychosocial traits: Tae-Yang ( 태양, 太陽) or "greater yang", So-Yang (소양, 小陽) or "lesser yang", Tae-Eum (태음, 太陰) or "greater yin", and So-Eum (소음, 小陰) or "lesser yin".