Let us consider what are the facts scientifically known concerning the interaction between mind and matter. Fundamentally they amount to this: that a complex piece of matter, called the brain, is the organ or instrument of mind and consciousness; that if it be stimulated mental activity results; that if it be injured or destroyed no manifestation of mental activity is possible. Moreover, it is assumed, and need not be doubted, that a portion of brain substance is consumed, oxidised let us say, in every act of mentation: using that term in the vaguest and most general sense, and including in it unconscious as well as conscious operations. Suppose we grant all this, what then? We have granted that brain is the means whereby mind is made manifest on this material plane, it is the instrument through which alone we know it, but we have not granted that mind is _limited_ to its material manifestation; nor can we maintain that without matter the things we call mind, intelligence, consciousness, have no sort of existence. Mind may be incorporate or incarnate in matter, but it may also transcend it; it is through the region of ideas and the intervention of mind that we have become aware of the existence of matter. It is injudicious to discard our primary and fundamental _awareness_ for what is after all an instinctive inference or interpretation of certain sensations. The realities underlying those sensations are only known to us by inference, but they have an independent existence: in their inmost nature they may be quite other than what they seem, and are in no way dependent upon our perception of them. So, also, our actual personality may be something considerably unlike that conception of it which is based on our present terrestrial consciousness—a form of consciousness suited to, and developed by, our temporary existence here, but not necessarily more than a fraction of our total self.