In life all things have two opposite aspects. If light exists then darkness exists as well. Wherever there is an "up" there will also be a "down". If something has a front it must have a back. Something that is born will eventually die. If something can be hot then cold exists. If something can expand then contraction is inevitable. There are no advantages without some disadvantages; there are no disadvantages without some advantages. All the opposites one perceives in the universe can be reduced to the opposing forces of Yin and Yang. This changing combination of negative and positive, dark and light, cold and hot is what keeps the world spinning. In our individual lives all change can be seen as one opposite becoming the other. As something reaches an extreme it always gives way to its opposite. Just as the seasons cycle through summer-fall-winter-spring and create opposite periods of hot and cold, Yin and Yang cycle through active and passive, dark and light, strength and weakness.

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Yin represents everything that is feminine, dark, cold, contracting, receptive, and passive. It is the negative aspect of anything and its movement is down and inwards. Yang represents everything that is masculine, light, hot, expansive, forceful, and active. It is the positive aspect of anything and its movement is up and outwards. While these examples display Yin as weakness and Yang as strength, it is important to realize that everything in the world is really a mixture of the two. Because of this, things that we might expect to be weak or strong, because they clearly represent Yin or Yang, might turn out to be the opposite instead. Each representation of Yin and Yang also contains within it its own balance of Yin and Yang. Man is considered Yang and woman, Yin. But if the man is small, pale, and weak while the woman is big, robust, and strong, she would have more Yang than the man and he more Yin than she. This is by no means to be taken as disparaging to women…or men for that matter. Each of us must have a balance of both Yin and Yang to be complete.