The concept of Yin and Yang is one of the key fundamental principles that must be clearly understood before one can successfully practice Feng Shui. Put simply, Yin and Yang is represent the duality that is present throughout all of creation. This duality illustrates the principle of change.
Change is constant in this life. All living things move from birth to death. The seasons progress from spring to summer to autumn then to winter. The ancients recognized these changes, and the duality that lay behind them. They expressed this duality in the principle of Yin and Yang. The most basic level of Yin and Yang characteristics refers to two types of energies: moving and unmoving, or passive and active.
The original Chinese characters for Yin and Yang represented the shady (northern) side of a hill and the sunny (southern) side of a hill. The shady side represented Yin and the sunny side represented Yang. Yin and Yang constantly move, transforming into one another. Because of this, nothing is completely Yin or completely Yang. Everything that exists is composed of both polarities in varying measures. One of the fundamental ideas behind Yin and Yang theory is that when something reaches the limit of Yin it becomes Yang, and vice versa.
When studying the external environment, mountains are seen as Yin and water is seen as Yang. This is because mountains are still and lack of motion is a characteristic of Yin. On the other hand, water is always moving, even when captured inside a container. Motion is characteristic of Yang. When mountain and water landforms meet, new Qi is produced from the interaction between Yin and Yang.
In the internal environment of a house or other building, the main door and living room is considered Yang because there is movement and activity there. This would also apply to doors and passageways, and any other areas where there is a lot of natural sunlight and/or activity. Such rooms should not be kept too dark or have too many plants that block the sunlight. Bedrooms, on the other hand, are considered Yin rooms because we sleep there. A bedroom should be located and arranged in such a way as to promote Yin Qi. Otherwise, our sleep will suffer and this will impact our health in the long term. The kitchen stove is also considered Yin because it is not in constant use. Also, the food prepared there has a direct effect on health, and health aspects are within the Yin domain.
It is virtually impossible to list every classification that can be divided into yin and yang, but some examples include night and day, inside and outside, high and low, forward and reverse, action and inaction, positive and negative, odd and even, physical and mental, real and imaginary, conscious and unconscious, time and space, hard and soft, fast and slow, hot and cold, etc. In the Yi Jing, Yang is represented by a whole line and Yin by a broken line. Since a whole line can be seen as one thing and the broken line can be seen as two things, odd numbers are correlated with Yang and even numbers with Yin.
The Daoist concept of the beginning of the universe states that all existence emerged from a great void called Wuji. This void is represented by a circle. The circle is both empty and full at the same time, and is a representation of possibility.
At some point, a division began to form within the void, and motion began to take whole. This is represented by the Taiji. The Taiji represents everything that we as human beings can conceive of, but does not actually consist of everything that actually exists like the Wuji does. The word Taiji means Great Ultimate.
Originally, Yin and Yang existed in a blended state within the Taiji, but over the course of time they separated more and more until the difference between them became clear. At this point, the Taiji could be represented by the familiar “yin-yang” symbol that is so common today. In this symbol, black represents Yin and white represents Yang. The Taiji symbol should actually be visualized as a sphere that is in constant motion, not just a flat, static shape. The Yang half of the Taiji is continually changing to Yin, and vice versa. This transformation is symbolized by the dot of Yin within Yang and the dot of Yang within Yin.
Although the Taiji symbol can technically be drawn in a variety of ways, the accepted “correct” way to orient it is with the white half positioned on the left, with the “head” pointing up. This is because the Chinese envision the spring to be located in the east, which is associated with the left side, and the summer with the south, which is associated with the top. Since spring and summer are Yang seasons, it stands to reason that the white half of the symbol would occupy those sections, with the largest yang area located in the section associated with summer, the maximum yang season. In contrast, the west is associated with autumn and the right side, so the yang portion of the Taiji symbol begins to show itself in the right portion of the image. Winter is associated with the north and the bottom of the circle, and winter is the season of maximum Yin, so the largest part of the Yin half of the Taiji is located at the bottom of the symbol.
Yin and Yang cannot exist without each other. They are like two sides of a coin, and can never be separated. Pure Yin would not have life, and pure Yang would not have growth. It is very important that we maintain a healthy balance of both Yin and Yang in our environments for feng shui to be at its most effective. In fact, balancing Yin and Yang properly is one of the most basic and powerful feng shui cures that one can apply.
An excess of Yin energy can lead to fatigue, depression and apathy. Life is stagnant and there is no progress. Excess Yang energy, on the other hand, can cause anxiety, headaches and irritability. Life rushes by too quickly, and there is no time to enjoy the little things in life. It is important to note that balancing Yin and Yang does not necessarily mean that the energies should be in completely equal portions. Certain areas should be kept more yin, and other areas should be kept more yang.
In the external environment, Yin and Yang can be balanced by virtue of studying the shapes of landforms. Mountains are generally considered Yin because they are stable, but when mountain ranges contain a lot of peaks and valleys, the imitation of motion in the up-and-down shapes represents Yang within the Yin.
Water is considered Yang in nature, but when water is collected and kept relatively still, it is considered Yin within Yang. Ponds and tranquil lakes are examples of relatively Yin water.
In both of these cases, the best land sites are those where there is Yang within Yin or Yin within Yang. This becomes especially important where a site does not contain both Mountain and Water landforms. Generally, the ideal proportion is said to be three-fifths Yang to two-fifths Yin.
| Yin | Yang |
| Dark | Bright |
| Night | Day |
| Contracting | Expanding |
| Inside | Outside |
| Cold | Hot |
| Wet | Dry |
| Female | Male |
| Soft | Hard |
| Internal | External |
| Unseen | Seen |
| Dead | Alive |
| Dense | Diffuse |
| Earth | Heaven |
| Passive | Active |
| Gentle | Aggressive |
| Heavy | Light |
| Moon | Sun |
| Receptive | Providing |
| Lower | Higher |
