Ayurvedic philosophy indicates that everything in the universe is made up of 5 elements; fire, air, water, earth and space. Air represents all that is gaseous, earth represents matter that is solid, all liquids are represented by water, fire represents any matter that can transform. Space represents the element in which the other 4 exist.
In our bodies, as in nature, these 5 elements co-exist in a way that is by and large harmonious and where no one element dominates another perpetually. For this harmony to exist, there has to be a force that manages a relationship between the elements of nature. In paired relationships, the forces guiding them are called the Doshas.