Man's soul nature as his own inner world is different from his bodily nature. When attention is turned to even the simplest sensation, what is personally his own comes at once to the fore. Thus no one can know whether one person perceives even a simple sensation in exactly the same way as another. It is known that there are people who are color-blind. They see things only in various shades of grey. Others are only partially color-blind. Because of this they are unable to distinguish between certain shades of color. The picture of the world that their eyes gives them is different from that of so-called normal persons. The same holds good more or less in regard to the other senses. Thus it will seem without further elaboration that even simple sensations belong to the inner world. I can perceive with my bodily senses the red table that another person perceives but I cannot perceive his sensation of red. We must, therefore, describe sensation as belonging to the soul. If this single fact is grasped quite clearly, we shall soon cease to regard inner experiences as mere brain processes or something similar. Feeling must link itself with sensation. One sensation causes us pleasure, another displeasure. These are stirrings of our inner life, our soul life. In our feelings we create a second world in addition to the one working on us from without. A third is added to this — the world of the will. Through the will we react on the outer world thereby stamping the impress of our inner being upon it. The soul of man, as it were, flows outwards in the activities of his will.
The actions of man differ from the occurrences of outer nature in that they bear the impress of his inner life. Thus the soul as man's own possession stands confronting the outer world. He receives from the outer world the incitements, but he creates in response to these incitements a world of his own. The body becomes the foundation of the soul being of man.