Mr. Herbert Spencer, in his remarkable investigation of "The Principles of Psychology," posits "mind" as always implied in sentiency, and as necessary to the genesis of any phenomenon, even the "first nervous shock" of a sensitive being. Recognizing the law of scientific idealism, he has seen, too, that our objective world is made up, at the perceptional outset, of such shocks. Again, he has proved, with great detail, that the action of mind is always of one general nature, whether in the lowest animal instinct or the highest conscious reason. But back at the first nervous shock, Mr. Spencer _stops_ with mind, and says that at the next regress it becomes "unknowable." Yet nearly a hundred years before this investigation Kant showed precisely what this so-called "unknowable" _is_. He showed that mind, in all stages and states--mind in itself--is a synthetical unity of awareness. In germ, as "unconscious understanding"--as the mind of sense--its function is to be simply apprehensive of, and thus to conjoin in its instinctive cognizance, some "manifold" contained in a "nervous shock," or in various sense-effects, into some _unity_; which then, as _itself apprehended_, or _made a reflex_, becomes an impression, an image, an object. CHAPTER XIII. A SPECIAL LOOK AT SPACE AND TIME. Through scientific idealism, fully examined, Kant proved that matter is a manufacture of sense. We have not followed the order of his work, but have gone straight to the heart of it. His own beginning was the dissection of space and time. Still, he implied therein, if only in one remark, all that has here been stated. "If I take [says Kant] from our representation of a body, all that the understanding thinks as belonging to it, as substance, force, divisibility, and also whatever belongs to sensation, as impenetrability, hardness, color, there is still something left us from this empirical intuition, namely _extension and shape_. These belong to pure intuition, which exists _a priori_ in the mind, as a mere form of sensibility, and without any real object of the senses or any sensation."