Cycle of Birth

Metal produces water - Metal is a solid matter. When melted, metal turns into liquid form. This is why we say metal produces water.

Water produces wood - All plants rely on water for nourishment. Without water, plants cannot survive. This is why we say water produces wood (in the form of plants).

Wood produces fire - In the ancient time, wood is the fuel required to keep a fire burning. This is why we say wood produces fire.

Fire produces earth - Wood, after being burnt, transformed into ashes which becomes earth. This is why we say that fire produces earth.

Earth produces metal - Most, if not all metal and minerals are digged and retrieved from the earth. This is why we say that earth produces metal.

Therefore the cycle of birth has the metal producing water, water producing wood, wood producing fire, fire producing earth, and in turn, earth producing metal. Every element played two role in this cycle - producing another element, and in return, get produced by another element. I often refer this as producer and producee. The producer of water is metal and the producee of water is wood.