A Soyangin has a physical shape of an upside-down triangle.
By David Lee, L.Ac.
A Soyangin is Lesser Yang primary and Greater Yang secondary
A Soyangin is defined as a big Spleen and small Kidney, which are excessive Earth and deficient Water, respectively. Therefore, the upper middle burner Earth is physically larger than the lower burner Water.
Furthermore, it has a secondary aspect of a Greater Yang, which has excessive Metal Lung and deficient Wood Liver. Consequently, the physical shape of the upper burner Metal is larger than the lower middle burner Wood.
One can use a ruler to measure the width of five lines, which reveals the size of the four burners. The measurements can be compared to objectively identify the four Sasang constitutions. A majority of a population has these characteristic shapes.
The distinctive torso shape of a Soyangin is a down-triangle that gradually narrows from top to bottom. Although there is some variation between individuals, one can observe the generally triangular shape.
The shoulder is broad and wide in respect to the overall shape of the individual’s physique. Each succeeding line is narrower than the previous line. Therefore, the shoulder 1st line is the widest, the chest 2nd line is shorter, and so on until the ilium 5th line is the narrowest.
The ilium 5th line is shorter than the stomach 3rd line, indicating a Lesser Yang. An umbilical 4th line that is shorter than the stomach 3rd line indicates a Greater Yang. A shoulder 1st line longer than the ilium fifth line also indicates a Greater Yang.