The lines forming these trigrams are either whole (male) or broken (female). Each Trigram consists of three male or female lines; and combined in various combinations; the Trigram symbolizes heaven, earth, water, fire dampness, wind thunder or mountains.
The trigrams can be superimposed upon each other, and in this way 8 x 8 = 64 hexagrams are obtained.
These 64 hexagrams provide the essential text of the Chinese oracle-book. The 64 hexagrams covers all human conditions and occasions - a kind of inspired formula for interpreting events in the world.
According to a legend, the system of trigrams and hexagrams was developed by Zhou-gong, the relative and political adviser of the first Emperor of the Zhou Dynasty (from c. 1050 BC). The trigrams are often to be found on the garments of Taoist priests and on the walls, ceiling and beams of Chinese temples.
Originally, the Trigram was considered a symbolic representation of the Family nucleus e.g. made up of the Father, Mother, Elder Son, Middle Son, Younger Son, Elder Daughter, Middle Daughter and Younger daughter. This is still true. In fact, the Trigram is more than this. If you look at the table below, the Trigram also represents the time and seasons. For example: K'an represents Winter, Ken = Late Winter, Chen = Spring etc.
Rain drops collect into streams, river & eventually to a heavy flow into a lake or the sea