This Symbol(Yin-Yang) represents the ancient Chinese understanding of how things work. The outer circle represents "everything", while the black and white shapes within the circle represent the interaction of two energies, called "yin" (black) and "yang" (white), which cause everything to happen. They are not completely black or white, just as things in life are not completely black or white, and they cannot exist without each other.
While "yin" would be dark, passive, downward, cold, contracting, and weak, "yang" would be bright, active, upward, hot, expanding, and strong. The shape of the yin and yang sections of the symbol, actually gives you a sense of the continual movement of these two energies, yin to yang and yang to yin, causing everything to happen: just as things expand and contract, and temperature changes from hot to cold.
The Yin-Yang in medicine
The concepts of Yin and Yang and the Five Agents provided the intellectual framework of much of Chinese scientific thinking especially in fields like biology and medicine. The organs of the body were seen to be interrelated in the same sorts of ways as other natural phenomena, and best understood by looking for correlations and correspondences. Illness was seen as a disturbance in the balance of Yin and Yang or the Five Agents caused by emotions, heat or cold, or other influences. Therapy thus depended on accurate diagnosis of the source of the imbalance.
According to legend the Yellow Emperor said:
" The principle of Yin and Yang is the foundation of the entire universe. It underlies everything in creation. It brings about the development of parenthood; it is the root and source of life and death it is found with the temples of the gods In order to treat and cure diseases one must search for their origins.
Heaven was created by the concentration of Yang, the force of light, earth was created by the concentration of Yin, the forces of darkness. Yang stands for peace and serenity; Yin stands for confusion and turmoil. Yang stands for destruction; Yin stands for conservation. Yang brings about disintegration; Yin gives shape to things....
The pure and lucid element of light is manifested in the upper artifices and the turbid element of darkness is manifested in the lower orifices. Yang, the element of light, originates in the pores. Yin, the element of darkness, moves within the five viscera. Yang, the lucid force of light truly is represented by the four extremities- and Yin the turbid force of darkness stores the power of the six treasures of nature.
Water is an embodiment of Yin as fire is an embodiment of Yang. Yang creates the air, while Yin creates the senses, which belong to the physical body When the physical body dies, the spirit is restored to the air, its natural environment. The spirit receives its nourishment through the air, and the body receives its nourishment through the senses "If Yang is overly powerful, then Yin may be too weak. If Yin is particularly strong, then Yang is apt to be defective.
If the male force is overwhelming, then there will be excessive heat. If the female force is overwhelming, then there will be excessive cold. Exposure to repeated and severe heat will induce chills. Cold injures the body while heat injures the spirit When the spirit is hurt, severe pain will ensue. When the body is hurt, there will be swelling. Thus, when severe pain occurs first and swelling comes on later, one may infer that a disharmony in the spirit has done harm to the body. Likewise, when swelling appears first and severe pain is felt later on, one can say that a dysfunction in the body has injured the spirit....
Nature has four seasons and five elements. To grant long life, these seasons and elements must store up the power of creation in cold, heat, dryness, moisture, and wind. Man has five viscera in which these five climates are transformed into joy, anger, sympathy, grief. and fear. The emotions of joy and anger are injurious to the spirit just as cold and heat are injurious to the body. Violent anger depletes Yin; violent joy depletes Yang. When rebellious emotions rise to Heaven the pulse expires and leaves the body When joy and anger are without moderation, then cold and heat exceed all measure, and life is no longer secure. Yin and Yang should be respected to an equal extent.
Where does the Yin Yang Symbol come from?
is a well-known Chinese Yin Yang symbol. Sometimes it's called Tai-Chi symbol. The Tai-Chi is from I-Ching. The I-Ching is the greatest foundation of Chinese philosophy. It's development is from the natural phenomena of our universe.
Because I-Ching comes from nature, it is believed it should be natural and easy to understand.
The Chinese characters of I-Ching are . The second character means a book, a profound book. The first character means ease or change. Since I-Ching is easy, some people call it as "The Book of Ease" or "The Book of Changes". The original Chinese character of is , which is a symbol combining the sun (top) and moon (bottom). It's simpler for people to understand the philosophy by talking about the sun (Yang), moon (Yin) and universe. After observing the universe, ancient Chinese found that the universe is changing every day. Although it changes every day, it also has seasonal and annual cycles. From these cycles the unchanging rules are created.
By observing the sky, recording the Dipper's positions and watching the shadow of the Sun from an 8-foot (Chinese measurement) pole, ancient Chinese determined the four directions. The direction of sunrise is the East; the direction of sunset is the West; the direction of the shortest shadow is the South and the direction of the longest shadow is the North. At night, the direction of the Polaris star is the North.
They noticed the seasonal changes. When the Dipper points to the East, it's spring; when the Dipper points to the South, it's summer; when the Dipper points to the West, it's fall; when the Dipper points to the North, it's winter.
When observing the cycle of the Sun, ancient Chinese simply used a pole about 8 feet long, posted at right angles to the ground and recorded positions of the shadow. Then they found the length of a year is around 365.25 days. They even divided the year's cycle into 24 Segments, including the Vernal Equinox, Autumnal Equinox, Summer Solstice and Winter Solstice, using the sunrise and Dipper positions.
They used six concentric circles, marked the 24-Segment points, divided the circles into 24 sectors and recorded the length of shadow every day. The shortest shadow is found on the day of Summer Solstice. The longest shadow is found on the day of Winter Solstice. After connecting each lines and dimming Yin Part from Summer Solstice to Winter Solstice.
Yang is like man. Yin is like woman. Yang wouldn't grow without Yin. Yin couldn't give birth without Yang. Yin is born (begins) at Summer Solstice and Yang is born (begins) at Winter Solstice. Therefore one little circle Yin is marked on the Summer Solstice position. Another little circle Yang is marked on the Winter Solstice position. These two little circles look like two fish eyes.In general, the Yin Yang symbol is a Chinese representation of the entire celestial phenomenon. It contains the cycle of Sun, four seasons, 24-Segment Chi, the foundation of the I-Ching and the Chinese calendar.
In the aspects of magic we can make use of the Yin-Yang.
Thank you for reading
Taken from: http://beholders.org/mind/artshistoryculture/100-meaningyinyang.html