The yin and yang is like a candle. Yin represents the wax in the candle. The flame represents the yang. Yin (wax) nourishes and supports the yang (flame). Flame needs the wax for its existence. Yang consumes yin and, in the process, burns brightly. When the wax (yin) is gone, the flame is gone too. Ying is also gone at that time. So, one can see how yin and yang depend on each other for their existence. You cannot have one without the other.

The body, mind and emotions are all subject to the influences of yin and yang. When the two opposing forces are in balance we feel good, but if one force dominates the other, it brings about an imbalance that can result in ill health.

One can compare the concept of yin and yang to the corresponding principle of tridoshas in Ayurveda, the ancient remedy from India. Ayurveda proposes that every person has vata, pitta and kapha. When these are balanced, there is the state of perfect health. When there are imbalances then there is disease.

One of the main aims of the acupuncturist is to maintain a balance of yin and yang within the whole person to prevent illness occurring and to restore existing health. Acupuncture is a yang therapy because it moves from the exterior to the interior. Herbal and nutritional therapies, on the other hand, are yin therapies, as they move from the interior throughout the body. Many of the major organs of the body are classified as yin-yang pairs that exchange healthy and unhealthy influences.