The Yin and Yang Theory

Yin and yang represent the two opposing forces, the two extremes or the two opposite ends of things. For example, night and day, summer and winter, wet and dry, hot and cold, etc. Yin is night and yang is day. Night is resting and restoring; day is moving and growing. Night and day control the life of living organisms on earth. Without either one, life does not exist. But when either one becomes too dominating, it causes imbalance. The cosmic system has its own law in moving from one end of the extreme to the other in order to re-establish balance. This creates the indefinite cycle of suppression and rejuvenation. It is the reason why the natural resources on earth such as air, water, earth, wood and fire will never run out (see more explanation at the section on the five elements).

Chinese medicine sees many similarities between our bodies and the cosmic system. Our body has the natural ability to self-regulate, rejuvenate and re-establish balance. The Yin and Yang Theory is used to explain why sickness occurs and what treatments are required to get well. The concept is very sophisticated, but easy to understand and follow by most ordinary people. 

The five vital solid organs: the liver, heart, spleen, lungs and kidneys are the yin organs. The five companion hollow organs: the gall bladder, small intestine, stomach, large intestine and bladder are the yang organs. Each yin organ works with one yang organ in pair as one vital system. The liver system is the liver and the gall bladder. The digestive system is the spleen and the stomach. The kidney system is the kidney and the bladder. The heart system is the heart and the small intestine. The lung system is the lungs and the large intestine. Each Yang organ acts as the reservoir for its yin partner by storing the vital resources or waste materials generated and moving them to other parts of the body.    

There are constant flows of blood, fluid, energy or qi and nutrients throughout our body. When any flow is obstructed, we become sick. Chinese doctors treat sickness by determining where imbalance exists, and interpret the conditions in terms of yin and yang, hot and cold, and blood and qi. When one force is in excess, the doctor will either tame it or drain it or lift the opposing energy to contain the excess to re-establish balance. 

For example, when the body is suffering from a cold, it has an excess of yin. Symptoms of yin excess are tiredness, weakness, feeling cold, low body temperature, low activity and withdrawn. Yin excess can be transformed into yang excess with fever. Other yang symptoms are hyperactivity, feeling hot, feverish, acute, virulent, advancing and flourishing. For blood deficiency, the symptoms are dizziness, impaired vision, numb limbs, weak pulse, pale face, thin body, dry skin and dry hair. For qi deficiency, the symptoms are weakness, pale face and tongue, speaking with little energy and a low voice. 

When a problem is identified, foods and herbs of the opposing nature are used to bring back the internal balance. Besides internal treatment, Chinese medicine has external treatment modalities such as acupuncture, moxibustion, chi-gong, tai-chi, meditation, exercise and massage therapy to address the imbalance externally to speed up recovery.