The stone, however, _is_ unmistakably objective--is just the palpable thing that everybody takes it to be, out there in space. This is a given _fact of perception_--something, as Kant said, "never questioned in experience." As such _fact_, how can it be accounted for, when we know, at the same time, that the stone is nothing but a plexus of subjective states? How does the bunch of _internal impressions_ get _externalized_? What is the cause of this reflex, this "_re_-presentation"? It must be something inherent in the principle of _apprehension itself_, or the plexus of impressions would necessarily stay within us. Being wrought internally, it would remain internal. Hence, this "apprehension"--this element of instinctive synthetical awareness--must be in its nature a _double_--an entity which reproduces, or throws out before itself, whatever lot of sense-effects it receptively synthesizes, or binds together in a sheaf, known as some object. But all this, summed up, means only that mind, even in its lowest form of "unconscious understanding"--the simple automatic apprehension which shuts together certain effects on sense into a totality of them--must, _as being apprehension_, necessarily, though instinctively, apprehended its own product. Here is the full explanation of the amusing, iron-clad conception of Hobbes, that an "image," or a "color," is but an apparition unto us of "motion, agitation, or alteration" in some "internal substance of the head." The self-reflexiveness of "apprehension" is precisely the same thing, _in germ_, that the self-reflexiveness of "apperception" is, in _full self-consciousness_. The self-reflexiveness of apprehension, in the manufacture of phenomena, was named by Kant "_the transcendental synthesis of imagination_"--the word "imagination" standing on its roots, and meaning _the image-making faculty_. Phenomena, as reflex-conjuncts of sense-effects, are "produced"--put out--by this second function of apprehension; so Kant said he sometimes called it "productive imagination." It is that function of pure elemental, or _a priori_ awareness, which "_re_-presents" itself in the constitution of every object, as its _unity_, but a unity _shaped_ according to some object's filling of senses-effects. Hence Kant says: "This synthesis of the manifold of sensuous intuition, which is possible and necessary _a priori_, may be called figurative synthesis (_synthesis speciosa_)." Thus Kant found mind in sense, "unconscious understanding," the instinctive awareness of animal susceptibility, as it existed in himself, to be the literal objective basis of all phenomena--the first "material" unity of every "material thing." And he found this elemental source of all unity to be an innate self-activity--a self-seeing mirror, as it were--a double of receptiveness and reflectiveness. Here, at last, was the actual, _living thing_, of which Locke's "blank-tablet" had long been the still-born, stone figure.