What of the Spiritualistic theory? The pure Spiritualist denies to Matter all independent existence and regards it merely as a product of Spirit. But when he tries to apply this theory to the solution of the riddle of his own human nature, he finds himself caught in a tight place. Over against the "I," or Ego, which can be ranged on the side of Spirit, there stands directly the world of the senses. No spiritual approach to it seems open. It has to be perceived and experienced by the Ego with the help of material processes. Such material processes the Ego does not discover in itself, so long as it regards its own nature as exclusively spiritual. From all that it achieves by its own spiritual effort, the sensible world is ever excluded. It seems as if the Ego had to concede that the world would be a closed book to it, unless it could establish a non-spiritual relation to the world. Similarly, when it comes to acting, we have to translate our purposes into realities with the help of material things and forces. We are, therefore, dependent on the outer world. The most extreme Spiritualist, or, if you prefer it, Idealist, is Johann Gottlieb Fichte. He attempts to deduce the whole edifice of the world from the "Ego." What he has actually accomplished is a magnificent thought-picture of the world, without any empirical content. As little as it is possible for the Materialist to argue the Mind away, just as little is it possible for the Idealist to do without the outer world of Matter. When man directs his theoretical reflection upon the Ego, he perceives, in the first instance, only the work of the Ego in the conceptual elaboration of the world of ideas. Hence a philosophy the direction of which is spiritualistic, may feel tempted, in view of man's own essential nature, to acknowledge nothing of spirit except this world of ideas. In this way Spiritualism becomes one-sided Idealism. Instead of going on to penetrate through the world of ideas to the spiritual world, idealism identifies the spiritual world with the world of ideas itself. As a result, it is compelled to remain fixed with its world-view in the circle of the activity of the Ego, as if it were bewitched.