§ 137. We must now turn to the efforts which this doctrine has made to maintain itself against the sceptical trend of its own epistemology. For precisely as in the case of phenomenalism its dialectical principle threatens to be self-destructive. Immediate presence is still the test of knowledge. But does not immediate presence connote relativity and inadequacy, at best; an initial phase of knowledge that must be supplemented and corrected before objective reality and valid truth are apprehended? Does not the individuality of the individual thinker connote the very maximum of error? Indeed, spiritualism would seem to have exceeded even Protagoreanism itself, and to have passed from scepticism to deliberate nihilism. The object of knowledge is no longer even, as with the phenomenalist, the thinker's thought, but only his _thinking_. And if the thinker's thought is relative to him, then the thinker's act of thinking is the very vanishing-point of relativity, the negative term of a negating relation. How is a real, a self-subsistent world to be composed of such? Impelled by a half-conscious realization of the hopelessness of this situation, the exponent of spiritualism has sought to universalize his conception; to define an _absolute or ultimate spirit_ other than the individual thinker, though known in and through him. But it is clear that this development of spiritualism, like all of the speculative procedure of subjectivism, threatens to exceed the scope of the original principle of knowledge. There is a strong presumption against the possibility of introducing a knowledge of God by the way of the particular presentations of an individual consciousness. [Sidenote: Schopenhauer's Attempt to Universalize Subjectivism. Mysticism.]