Functions of Yin and Yang


Yin functions

To cool:

Yin must be able to cool the body adequately, so that Yang doesn't warm the body excessively.
E.g.: The Yin of the Kidney cools the Yang (fire) of the Heart.

To moisten:

Yin moistens the body, including the skin, hair, muscles, mucous membranes etc.
E.g.: The Yin of the Lungs moistens the skin.

To nourish:

Yin nourishes the body.
E.g.: The Yin (Blood) of the Liver nourishes the muscles and the tendons.

To calm:

Yin calms the activities of Yang. The calming function of Yin protects us from excessive activity and restlessness.
E.g.: The Yin of the Heart calms the spirit.

If Yin is weak, the functions of Yin can not be maintained. As a result, Yang will dominate in the body.