10. The Experience of the Soul's Will Nature

When we examine how the nature of the thinking-soul is connected with the head system, we find that it is devoted entirely to it, it is transformed, as it were, into the head organization. The head organization forms a physical and etheric replica of the part of the soul involved in thinking: therefore, when man really thinks in waking everyday life, he cannot actually observe the process of thinking in himself but must seek it in its replica in the physical and etheric processes of the brain and the rest of the nervous system. This is why the anatomy and physiology of the brain are the real domain for the physical part of a science of the soul, because the replicas of what goes on in thinking can really be observed in the structure of the brain, and thereby also in its processes.