Yin is associated with shade, the moon, cold, night, north and all that is hidden and covered. Water is cold of a yin nature and moves downwards.
Yang is associated with light, the sun, heat, summer, the south and all that is visible and open. Fire is of a yang nature and the flammes moves upwards and outwards.
Four characteristics of yin-yang
These two dynamic forces are in constant and perpetual mouvement. The following characteristics of yin and yang explain their constant interaction.
1 Yin and Yang are opposites
Their opposition is relative (hot-cold, day-night…) because neither is ever completely one or the other.
2 Yin and Yang are interdependant
One cannot exist without the other, they are two aspects of the same reality (day cannot exist without night, nor light without obscurity) and they cannot be separated.
3 Yin and Yang increase and decrease constantly
When yin increases, yang decreases simultaneously and vice versa. It is the perpetual cycle of days and seasons. As day sets in the shade lessens and when evening descends the moon and darkness take over.
4 Yin and Yang transform mutually
Extreme Yang ultimately transformes into yin and vice-versa. The extreme tension of one provokes its transformation.
Extreme fever (Yang) can lead to a state of shock (Yin)
The theory of Yin-Yang can be applied in the same way to our own organism. When an individual is healthy yin and yang are in harmony. This is not a static harmony but rather a dynamic one. On the contrary, when there is a yin-yang imbalance the individual is ill.
In other words when a person is in good health his body functions perfectly and yin-yang is in a state of equilibrium. However, when he is ill there is disharmony and his body will show signs of imbalance.
The goal of acupuncture treatment is to harmonize yin-yang and thus restore health and balance to the body.