All of us exist upon a threshold. This is what makes us what we are, and what allows us the command over energy and the subtle reality that comprises the bulk of our powers. We walk in two worlds at once, and although the bodies we have are but mortal, the spirit within is vast and eternal.
Each of us differs in the quality and quantity of energy we require to sustain us. The depth of our need is influenced by the strength of the connection between our bodies and our souls. Those of us who are more connected to our bodies need to take in less energy from those around us unless we are engaged in very draining spiritual work. Those who are balanced more on the spirit side of the threshold tend to enjoy greater powers and sensitivities, but their need for vital spirit is also increased.
Where on the threshold one falls affects not only the quantity and quality of energy required, but also what skills may be learned, what talents will be inborn, and how ones nature will manifest itself. It is crucial to understand these matters and how they affect the individual, especially in a Potential or in one who is verging upon awakening.
The caste system is an attempt to simplify the various threshold states. The castes are guidelines for understanding ourselves, our basic natures, and the role we play in our community. Although loosely based upon an ancient social system, the castes are not intended to become a hierarchy or social structure in this day and age. That time has long gone by. Instead, use the castes as what they are intended to be: guidelines for personal understanding which will hopefully explain some of the mysteries of why one person processes energy one way, and someone else has a very different experience and approach.
Keep in mind that the caste system is very limited. There are but three archetypes offered here, and not everyone will fit neatly into any of them. It is far more likely that each person will find within themselves qualities of two or more. We have been through many lifetimes, and our souls have grown and changed. We have learned much, and most of us have come a long way from what we once were. Discovering the caste that describes you the best may hold the key for understanding your basic nature and how to proceed in awakening to it, but use the caste solely as a tool. Do not try to become something you are not, and do not allow yourself to chafe beneath an archetype that does not suit you. In the end, you are you, with all your complexities and contradictions, and no simple word will ever be found to encompass all of these.