The four elements associated with the signs of the Zodiac break down the signs into the basic groupings of Fire, Earth, Air and Water. The natural world fits into these four classifications, whose basic characteristics -- the heat of fire, the stability of earth, the changeability of air and the fluidity of water -- can be applied to human nature. Besides the four elements, there are three qualities that influence the signs -- Cardinal, Fixed and Mutable. These qualities speak to a person's general attitude and the way they tackle a project.
