“experience.” But it is by no means a _tabula rasa_, and a merely passive mirror of the outer world, for it translates the stimulus thus received into quite a different language, and builds up from it a new reality, which is quite unlike the mathematical and qualityless reality without. And this activity on the part of consciousness begins on the very lowest stages. The simplest perception of light or colour, the first feeling of pleasure or discomfort, is a reaction of the psychical, which brings about something entirely new and unique. “The spirit is never passive.” That the psychical is not derivable from the physical, that it does not arise out of it, is not secondary to it, but pre-eminent over it, is not passive but creative; so much we have already gained to set over against naturalism. But its claims are even more affected by the fact of real psychical causality. We need not here concern ourselves with the difficult question, whether the mind can of itself act upon the body, and through it upon the external world. But in the logical consistence of naturalism there was implied not only a negative answer to this last question, but also a denial of the causality of the psychical, even within itself and its own domain. This is well illustrated in the figure of the cloud shadows. In consciousness state follows upon state, a upon b, b upon c. According to naturalism, b is not really the result of a, nor c of b, for in that case there would be independence of phenomena, and distinctness of laws in the psychical. But as all the states, a, b, and c, of the cloud shadows, depend upon states _a_, _b_, and _c_, of the clouds themselves, but do not themselves form a concatenation of causes, so all the states of the mind depend upon those of the body, in which alone there is a true chain of causes because they alone have true reality.