The author reached a level in meditation that rare people do. He says: I believe that the human physical system has two main compartments the outer or the upper, and the inner or the deeper. Most spiritual philosophers describe, what I call the deeper as subtle or astral body and diagrammatically depict it as being above the outer body. As I experienced, the second physical system exists inside the body itself; I call it the inner or the deeper physical. The two compartments are closely interlinked, with constant interaction, without a clear-cut line of demarcation and have a considerable overlap in functions and responses.