Kant must now piece together his two separated factors. Sensation, unrelated manifold of sensation, is _there_, thought, isolated, analytic thought, is _here_. Neither is knowledge in itself. What more natural than to put them together, and hold that knowledge is the union of a matter or stuff, of sensations, atomic in themselves, on one hand, and a form, or regulating principle of thought, empty in itself, on the other? We have two elements, both existing in isolation, and yet both useless for all purposes of knowledge. Combine them, and presto, there is science. Such a “transcendentalism” as this may well stick in the crop of scientific men. For consider what is involved in it: an _a priori_ factor, on one side, and an _a posteriori_, on the other. Kant, from one point of view, seems thus to have simply combined the weaknesses of empiricism and rationalism. He still continues to talk of experience itself as particular and contingent, and denies that it gives a basis for any universal laws. Aside from his effort in the “Kritik der Urtheilskraft” to overcome his original separation, special scientific laws are to him only more or less extensive generalisations from experience—as much so to him as to Locke, or Mill. Scientific men indeed, have accustomed themselves to this derogation of their own methods and results, and, as “inductive” logicians, indulge in it quite freely themselves. But an _a priori_ element, supplied by a thought fixed and separate, scientific men cannot do away with. Nor do I know any reason why they should. It is coming short, in my opinion, of the full stature of science to treat it as a quantitative and varying generalisation of contingent particulars, but this, at least, leaves what science there is free and unhindered. But _a priori_ elements supplied from outside the fact itself, _a priori_ elements somehow entering into the fact from without and controlling it—this is to give up the very spirit of science. For if science means anything, it is that our ideas, our judgments may in some degree reflect and report the fact itself. Science means, on one hand, that thought is free to attack and get hold of its subject-matter, and, on the other, that fact is free to break through into thought; free to impress itself—or rather to express itself—in intelligence without vitiation or deflection. Scientific men are true to the instinct of the scientific spirit in fighting shy of a distinct _a priori_ factor supplied to fact from the mind. Apriorism of this sort must seem like an effort to cramp the freedom of intelligence and of fact, to bring them under the yoke of fixed, external forms.