Orientation of the yin-yang symbol
The figure of the double spiral presents a strong similarity with the boundary line of the black and white halves of the yin-yang symbol and may be drawn vertically or horizontally:
Drawn vertically as in the above picture, the double spiral evokes the complement between Heaven and Earth, celestial and terrestrial poles, descending and ascending phases in relation to both streams of the cosmic force. As Heaven is above Earth, the clear area of the symbol, which is yang, should stand over the dark area, which is yin.
Drawn horizontally, the double spiral focuses mostly on the symmetry of both streams of the cosmic force. Considered at the same level, the two poles of the cosmic force are constantly exchanging their influences in a balanced way so that none of them prevails. In this case, the clear and dark areas of the yin-yang symbol are laying horizontally one over the other without any dominance of one of them.
The observer looking at the symbol may see it left or right oriented according to the rotation direction of either “fish” or “dolphins” representing yin and yang areas. As shown on the diagram below, the change of rotation direction consists of two symmetries, alongside the vertical and the horizontal axis respectively, which are providing a mirror image in comparison with each axis.
When gathered in a single image, both vertical and horizontal double spirals create a swastika, which is left or right oriented according to the yin-yang symbol orientation. Both branches of the swastika are related to the four compass points.
| Yin-yang symbol | Vertical | Horizontal | Together | Compass points |
|---|---|---|---|---|
| Left oriented |
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| Right oriented |
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The vertical branch is linked to the solstitial axis. Moreover, its upper part, related to the yang area of the symbol, may only be associated with light or South direction; its lower part, which is connected to the yin area, is obviously linked to darkness or North direction.
The horizontal branch is connected to the equinoctial axis. As before, its left part can only be related to East and its right part to West direction.
The compass points disposition related to the yin-yang symbol is in perfect accordance with the usual representation of Chinese maps and plans: South being at the “top” and North at the “bottom” 1.
Orientation choice
Now, the orientation choice between left and right depended, in ancient China, on which compass point the observer was facing.
Following Kouan Tseu who would have lived during the 7th century before our era, “Spring gives birth on the left, Autumn destroys on the right, Summer helps growing ahead, Winter puts in reserves behind”. According to the usual correspondence between seasons and compass points, South is clearly ahead and North behind. Therefore, the observer was facing South. Indeed, usually yin regarding the Cosmos, he was looking for his complement, which is yang. This is probably why the left direction going towards East, which is yang, was generally (but not always) preferred to the right direction.
Note that this preference for the left corresponds to a terrestrial perspective. Adopting the celestial way means to be yang regarding the Cosmos and yin towards the Principle. Therefore, the being was facing his complement, yin or North, and moving in direction of yang or East in order to initiate his descend towards yin. So, he was giving the preference to the right.
Despite the different nature of states of being associated with terrestrial and celestial ways, the pre-eminence was, in both cases, devoted to East considered as the luminous side. This is in complete agreement with a general analogy where Earth is a reverse image of Heaven, just like in a mirror. So, the left for the terrestrial way corresponds to the right for the celestial way
These orientation questions do not only seem complex, but are complex. We have not only to pay attention to any possible confusion between various associations, but also, within any association, to the predominance of left or right according to the celestial or terrestrial way considered.
1 back This way of representing maps is not as exceptional as we could think. It was notably used by the ancient Romans and still in use during the first part of the Middle Age.