things is substance is permanent--is a synthetic, and properly metaphysical judgment.”[286] In § 5 the principle of causality is also cited as an example of a synthetic _a priori_ judgment in metaphysics. But Kant still omits to draw a distinction between immanent and transcendent metaphysics; and as a consequence his classification of synthetic _a priori_ judgments remains thoroughly confused. They are taken as belonging to three spheres, mathematics, physics (in the relative sense), and metaphysics. The implication is that this threefold distinction corresponds to the threefold division of the _Doctrine of Elements_ into _Aesthetic_, _Analytic_, and _Dialectic_. Yet, as a matter of fact, the propositions of mathematical physics, in so far as they are examples of applied mathematics, are dealt with in the _Aesthetic_, and in so far as they involve concepts of motion and the like fall entirely outside the scope of the _Critique_, while the _Analytic_ deals with those _metaphysical_ judgments (such as the principle of causality) which are of immanent employment.[287] As the new paragraphs in the _Introduction_ to the second edition are transferred without essential modification from the _Prolegomena_, they are open to the same criticism. To harmonise B 17 with the real teaching of the _Critique_, it must be entirely recast. Instead of “natural science” (_physica_) we must read “pure universal natural science [= immanent metaphysics],” and for the examples given we must substitute those principles of substance and causality which are dealt with in the _Analytic_. The next paragraph deals with metaphysics in its transcendent form, and accordingly states the problem peculiar to the _Dialectic_. =Metaphysics.=[288]--This paragraph deals _explicitly_ only with transcendent judgments, but as the terms used are ambiguous, it is possible that those of immanent metaphysics are also referred to. The paragraph is not taken from the _Prolegomena_. The corresponding passage[289] in the _Prolegomena_ deals only with the judgments of immanent metaphysics. =The real problem of pure reason is contained in the question: How are synthetic a priori judgments possible?=[290]--Cf. above, pp. 26 ff., 33 ff., 43 ff. =David Hume.=[291]--Cf. above, pp. 61 ff. =A theoretical knowledge.=[292]--_i.e._ Kant explicitly leaves aside the further problem, whether such judgments may not also be possible in the practical (moral) and other spheres. =How is pure natural science possible?=[293]--The note which Kant appends shows that he is here taking natural science in the relative sense.[294] The same irrelevant instances are again cited. =As these sciences really exist.=[295]--Cf. below, p. 44 ff. =The poor progress which metaphysics has hitherto made.=[296]--Cf. _Preface_ to the second edition; _Prolegomena_, § 4, and A 175 ff.