The origins of Yin and Yang can be found in the Yijing, it can be seen in the sunny (yang) and shady (yin) sides of a hill, the same could be said for feelings, without sorrow (yin) we would not understand joy (yang).  In the Zhou dynasty (circa. 770 – 481 bce) yin and yang came to symbolise the two primal forces of Qi.

In Dao tradition everything originates from the great void – wuji (“wu” meaning none or without “ji” meaning limit.). Wuji is the compressed potential of everything before the beginning.  As a concept of understanding, wuji is the source, the spring of all knowledge and life.  Wuji is represented as an empty circle, symbolising an unbroken whole, constant motion, the beginning.

Wuji being without limit is without characteristic, as soon as one can discern or perceive and silence breaks, we are introduced to taiji.  The Taiji is a duality, the illustrated definition of Yin and Yang.  Taiji meaning “Great limit”, yet represents a greater whole.  Everything is both Yin and Yang.

Yin symbolises earths energy or force.  Yin is dark, female, cold, lower, under, docile, passive condensing, soft, wet.

Yang symbolises heavens energy or force.  Yang is light, male, heat, higher, above, form, active, expanding, hard, dry.

Neither is better or worse that the other, they both must exist for either to exist.

Yin and yang representative of polarity, there cannot be a top (yang) without a bottom (yin), no north (yang) without a south (yin), an inside (yin) without an outside (yang), no setback (yin) without the seed of an equivaleng success (yang).  The same can be said for circumstances and time; there can be no night (yin) without day (yang).

Nothing can be pure yin or pure yang, hence the inverted dots present within the yin and yang symbols.  Nothing can be so bad as to not have good present at the same time.  The darkest night is not devoid of all light.

Yin and yang are not independent forces, rather a way to conceive a universal principle.  The s-like line running through the taiji is representative of the fact that nothing is ever fixed.  Everything is in constant change, the rhythms of the tides, the ellipse of the moon around the earth, the earth around the sun.

Fu Xi sought to understand this balance.  In his time people used marks to count, cut notches into sticks to count sheep thereby it must have been natural for him to represent yin and yang as lines.  A single sold line to represent yang and a broken line to represent yin.  From these two lines he began to illustrate his understanding.

                                           

The next step in understanding the fundamentals used in Feng Shui, please click the link below to understand the importance of the Yijing or "Book of Changes".