Natural herbs do not heal diseases any better than synthetic drugs. They do however help the body to fight disease, strengthen the body's immune system, and help to harmonize the body's functions. Herbal medicine can be dangerous if the “judicious use of knowledge” is not applied. A good knowledge of herbs is desired.
Traditional Chinese Medicine has Four Natures, Five Tastes, Four Actions, and the Meridian Attribution. The four natures of herbs are: cold, hot, warm, and cool. The herbs that are used to treat hot-type diseases are mostly cold or cool. Herbs that are used to treat cold-type diseases are mostly warm or hot. The “Nei Jing” says if it is cold, heat it; if it is hot, cool it. “The Shen Nong Ben Tsao Jing” says “use hot herbs (herbs of a hot nature) to treat cold-type disease; use cold herbs to treat hot-type diseases”. There are some herbs with a very gentle nature and they are called gentle, rather than hot or cold. Actually, every gentle herb may be said to be slightly on the warm or cool side, so we can still use the four natures.
The Five Tastes of Herbs
The five tastes of herbs are spicy, sour, sweet, bitter, and salty. There is a bland taste, which is classified as sweet; a mild sweet is bland. Different tasting herbs have different functions relating to the body. Each herb has its taste and nature. Herbs with the same nature may have the same taste and may have different natures. Therefore, the study of tastes and natures can be very complicated. The Nei Jing says spicy and sweet tastes move fast so they belong to yang. Sour and bitter tastes move downwards so they belong to yin. Salty taste moves downward too, so it also is yin. Bland taste permeates so it belongs to yang. Thusly spicy, sweet, and bland attributes are yang and sour, bitter, and salty attributes are yin.
The Four Actions of Herbs
The four actions of herbs are: ascending, descending, floating, and sinking. These four actions are related to the human body. The great Herbalist Li Dong-Yuan said, “herbs have the properties of ascending, descending, floating and sinking, transformation, giving birth, growth, harvesting, storing, and completion”. To match the four seasons, spring ascends, summer floats, autumn harvests, winter stores, and the central earth transforms. Herbs whose taste is weak will ascend and rise (give birth); herbs whose natures are weak will descend and restrain (harvest); herbs whose natures are strong will float and grow. Herbs whose taste are strong will sink and store; herbs whose nature are gentle and tastes are bland will transform and complete. Yang ascends, Yin descends, Yang floats, and Yin sinks. Spicy, sweet, and bland are the yang of the earth. Sour, bitter and salty are the yin of the earth. However, herbs that are light will usually ascend or float and herbs that are heavy will usually sink or descend. Flowers and leaves will float while seeds or roots will descend or sink. Keep in mind that Chinese Herb Medicine also includes the mineral and animal products, which have their own properties.
The Meridian Attribution of Herbs
The different herbs can affect the functions of the body differently. If a person has a hot type disease, the herbs used must be cool or cold, and if the person suffers from a cold type disease the herbs that should be taken are warm or hot. A hot type disease may be the liver-heat or stomach-heat; a cold type disease may be the spleen-cold or the lung-cold. Herbs that can purge the liver heat may not be able to purge the stomach heat; herbs that can warm the spleen-cold may not be able to warm the lungs-cold. So different herbs affect the functions of different organs. These functions of the herbs and the 12 meridians can be closely related and this is what is meant by the meridian attribution of herbs.