I Ching Explorer

Five Primary Elements
According to classic Chinese philosophy everything in the world is begeted by one of Five Primary Elements - Earth, Metal, Water, Wood and Fire. It is being said that these Five Elements interact and influence each other in a cyclic manner begeting all material things in the Universe.
Two Cycles
There are two main cycles in interactions of primary 5 elements – generating cycle and controlling (overcoming) cycle.
While elements in the generating cycle have the power to "create" each other, the elements in the controlling cycle show us which elements control and defeat other primary elements. According to Chinese tradition, there is no superior and no inferior element(s) among Five Elements of the Mother Nature. All Five Elements are equally important and should form a balance, while being in constant move and cyclical change. For example, Water begets Wood and Wood begets a Fire (generating cycle). But at the same time Fire can melt the Metal which in turn can cut a Wood (controlling cycle).
Chinese sages believed that 5 Elements are not only in constant support, but also are in competition with each other, and this is what results in changes.
Water gives boldItrth to Wood
Wood gives birth to Fire
Fire gives birth Earth
Earth gives birth to Metal
Metal gives birth to Water

So, as we can see here, each element creates some other element and it happens in a circular manner – Water creates Wood but eventually gets itself created by other element - Metal. There is no beginning neither the end in this creation loop and no element is more important than others.

But every creation must be accompanied by distraction. So, here it is another loop.
Water defeats Fire (water can extinguish a fire).
Fire defeats Metal (fire can melt a metal).
Metal defeats Wood (metal can cut a wood).
Wood defeats Earth (tree roots can penetrate soil).
Earth defeats Water (earth can adsorb water).

And we can see the same circular manner again – Water defeats Fire, but in turn gets eventually defeated by Earth.

In a more detailed level, each of two main interaction cycles - generating and controlling respectively - can be divided into 5 additional interaction types.
The five generating interactions are - fueling, forming, containing, carrying, and feeding.
The five overcoming interactions are - melting, penetrating, separating, absorbing, and quenching.

It is being said, for example, that Wood fuels (creates) Fire and Fire melts (distructs) Metal.

Main Qualities
Main qualities of 5 Elements are:
Wood - rising, growing, development (of action), impulse, expansion, decampment.
Fire - embodiment, definition, action, ascending, dynamic phase, design.
Earth - nurishing, alteration, transformation, transmutation, change, conversion.
Metal - sinking, contraction, discerning, declining.
Water - contemplation, calmness, descending, (re)consideration, yielding, observation, reflection.

Note also, that according to circles of life, each Element has many correspondences in different layers of physical world. Most important of them are: directions, colors, seasons of year, taste and organ system of human.

5 Elements and Human Body
Traditional Chinese medicine considers human body to be a copy of Universe. And if everything in Universe can be made out of 5 primary elements, so a human body can.
Liver & Gallbladder
Heart & Small Intestine
Spleen & Stomach
Lungs & Large Intestine
Kidney & Urinary Bladder

5 Elements - Integral View
Bringing together all pieces, revolving around 5 primary elements, we will get the following integral view.