Written by the disciples of a great physician: Ye Tian Shi -> 1667-1746.

The treatise is called We Re Lun (Warm-Heat Treatise). In the treatise, a method is defined that is called Wei Qi Ying Xue (the Four Layers).

The Four Layers diagnoses and treats febrile diseases caused by attacks of heat.

It differs from the diagnosis of the 6 levels in that the latter is used in case of attack of cold (from tai yang towards yang ming and can continue ...).

Both are used in diseases with fever.

Superficial Layers

The disorders are at the level of Qi.

• The Wei Layer comprises the skin (surface) and the Lungs (superficial, with its function of distribution and descent).
• The Qi Layer comprises Lungs, chest, diaphragm (where pathogenic energy can remain), stomach, intestine, gall bladder. It includes all its symptoms.

Deep Layers

More substantial disorders where Yin matter is affected, disorders at the level of Xue.

• The Ying Layer includes the repercussions at the level of Heart Master (Xin Bao, pericardium, what envelops the heart) and Heart.
• The Xue Layer is the deepest layer. It affects Heart, Liver and Kidneys.