According to the Ancient Orientals, natural processes do not occur randomly, but in an orderly, evolutionary manner following phases or stages of energy: THE 5 PHASES OF ENERGY or the 5 elements.
Each element is represented by a symbol: Water, Wood, Fire, Earth and Metal.
This theory contemplates the fact that no phenomenon of nature remains static, everything changes continually at its own pace.

Just as climates exist within seasons, emotions are the main forces within the human psyche. We all experience moments of anger, joy, worry, sadness and fear in the course of our daily lives. These emotions are often appropriate. It is natural to feel anger when we are frustrated, happiness when we are satisfied, pensiveness when we turn our attention inwards, sadness after a loss and frightened by danger. However, when one of these states dominates our inner experience or our external behavior, it interferes with the conduct of our daily life and alters the smooth flow of Qi or energy.

Eastern philosophy considers the inseparable beings of its environment, the earth and the sky. The sky drops electromagnetic energy on the earth in the form of solar rays and other stellar and planetary radiations; This descending energy squeezes the things on the earth, producing contractile effects. In turn, the earth, which behaves like a giant magnet, in its movement generates an electromagnetic field that permeates everything that inhabits it, its force goes from the inside out, producing expansive effects.
We are on earth and act as antennas to collect the electromagnetic forces of the sky and earth that carry our body of vital energy (the Ki of the Japanese or the Chinese Chi).

Yang constitution: broad bone structure, face with broad jaw compared to forehead, broad shoulders, shape general bone structure square, reddish complexion, iris with stroma (tissue) dense, strong musculature, body temperature normal high state. They are very vital people, with fast and safe movements.
Yin constitution: narrow bone structure, narrow jaws compared to forehead, narrow shoulders, elongated general shape, pale complexion, little dense stroma (iris tissue), soft musculature, low normal body temperature. They are people with little vitality, their movements are slow and unsafe.