The Earlier Heaven (先天, xiāntiān, "before heaven") is one of the two classic ways of arranging the eight trigram figures in a circle. It stands for ideal balance: each trigram faces its opposite, as if the world were at rest before it starts to move.
The layout
In Chinese diagrams, south is at the top. The trigrams sit like this:
- Heaven in the south, facing Earth in the north.
- Fire in the east, facing Water in the west.
- Lake in the southeast, facing Mountain in the northwest.
- Thunder in the northeast, facing Wind in the southwest.
Each facing pair always adds up to three yang and three yin lines. Go around the circle and yang grows on one side while yin grows on the other.
Origins: tradition and scholarship
Tradition credits it to the sage Fu Xi, hence the name "Fu Xi arrangement." Its textual basis is in the Shuogua, one of the Ten Wings, which pairs Heaven and Earth, Mountain and Lake, Thunder and Wind, Water and Fire. But the diagram as we know it was spread by Shao Yong in the eleventh century, under the Song dynasty, and historians see it as a creation of that time built on the older text.
What it's used for
It's mainly used to think about order and symmetry, in cosmology and in methods like Plum Blossom. For the world in motion, the seasons and everyday directions, people use the Later Heaven. Both appear in The Eight Trigrams.