KANT
604
KANT
knowledge, so to speak, qualitatively, not quantita-
tivel}'. Now, the data of sensation represent only
the appearances (Erscheinungen) of things; there-
fore all sensation is confined to a knowledge of ap-
pearances. Sense-knowledge cannot penetrate to the
noumcnoi), the reality of the thing (Ditig-an-sich) .
(b) Taking up now the knowledge which we acquire by means of the understanding (Verstand), Kant finds that thought in the strict sense begins with judgment. As in the case of sense-knowledge, he distinguishes here the content and the form. The content of judgment, or in other words, that which the under- standing joins together in the act of judgment, can be nothing but the sense-intuitions, which take place, as has been said, by the imposition of the forms of space and time on the data of sensation. Some- times the sense-intuitions (subject and predicate) are joined together in a manner that evidently im- plies contingency and particularity. An example would he the judgment, " This table is square." With judgments of this kind the philosopher is not much concerned. Ho is interested rather in judgments such as " All the sides of a square are equal", in which the relation affirmed to exist between the subject and the predicate is necessary and universal. With regard to these, Kant's first remark is that their necessity and universality must be a priori. That nothing which is universal and necessary can come from experience is axiomatic with him. There must, then, be forms of judgment, as there are forms of sensation, which are imposed by the understand- ing, which do not come from experience at all, but are a priori. These forms of judgment are the cate- gories. It is hardly necessary to call attention to the contrast between the Kantian categories and the Aristotelean. The difference is fundamental, a difference in nature, purpose, function, and effect. The important point for the student of Kant is to determine the function of the categories. They serve to confer universality and necessity on our judgments. They serve, moreover, to bring diverse sense-intuitions under some degree of unity. But they do not extend our knowledge. For while representations (or intui- tions) without the categories would be blind, the cate- gories without representative, or intuitional, content, would be empty. We are still within the narrow circle of knowledge covered by our sense-experience. Space and time do not widen that circle; neither do the categories. The knowledge, therefore, which we acquire by the understanding is confined to the appearances of things, and does not extend to the noumenal reahty, the Ding-an-sich.
It is necessary at this point to explain what Kant means by the "synthetic a priori" judgments. The Aristotelean pliilosophers distinguished two kinds of judgments, namely, synthetic judgments, which are the result of a "putting-together" (synthesis) of the facts, or data, of experience, and analytic judgments, which are the result of a " taking-apart" (analysis) of the subject and predicate, without immediate reference to experience. Thus, "This table is round" is a synthetic judgment; " All the radii of a circle are equal" is an analytic judgment. Now, according to the .\ristoteleans, all synthetic judgments are a posteriori, because they are dependent on experience, and all analytic jmlgments are a priori, because the liond, or nexus, in them is perceived without appeal to experience. This classification does not satisfy Kant. lie contends that analytic judgments of the kind referred to do not advance knowledge at all, since they always "remain within the concepts [sub- ject and predicate] and make no advance beyond the data of the concepts". At the .same time he con- tends that the synthetic judgments of the Aristote- Icans have no scientific value, since, coming as they do from exi)erience, they mu.st be contingent and particular. Therefore he proposes to introduce a
third class, namely, synthetic a priori judgments,
which are synthetic because the content of them is
supplied by a synthesis of the facts of experience,
and a priori, because the form of universality and
necessity is imposed on them by the understanding
independently of experience. An example would be,
according to Kant, " Every effect must have a cause."
Our concepts of "effect" and "cause" are supplied by
experience; but the universality and necessity of
pnuciple are derived from the a priori endowment of
the mind. The Aristoteleans answer, and rightly,
that the so-called synthetic a priori judgments are all
analytic.
(c) In the third place, Kant's "Critique of Pure Reason" is occupied with the reasoning faculty (Vernunft). Here " ideas" play a role similar to that played in sensation and judgment by space and time and the categories, respectively. Examining the reasoning faculty, Kant finds that it has tliree distinct operations, namely, categorical, hypothetical, and disjunctive reasoning. To these, he says, correspond the three "ideas", the idea of the soul as thinking subject (psychological idea), the idea of matter as the totality of phenomena (cosmological idea), and the idea of God as the supreme condition of all reality (theological idea). He first takes up the idea of the soul, and, examining the course of reasoning of the psychologist who teaches the substantiality, imma- teriality, and immortality of the human soul, he pronounces that line of pliilosophical thought to be fallacious, because it starts with the false supposition that we can have an intuitive knowledge of the soul as the substantial subject of conscious states. Tliis, he claims, is an erroneous supposition, for, while we can and do know our conscious states, we cannot know the suliject of them. Rational psychology, then, makes a wrong start; its way is full of contra- dictions; it does not conclusively establish the im- mortality of the soul. Next, Kant subjects the cos- mological idea to a similar analysis. He finds that as soon as we begin to predicate anything concerning the ultimate nature of matter we fall into a whole series of contradictions, which he calls "antinomies". Thus, the propositions, " Matter had a beginning", "The world was created", are apparently no more true than their contradictories, "Matter is eternal", "The world is uncreated." To every thesis regard- ing the ultimate nature of the material universe an equally plausible antithesis may be opposed. The conclusion is that by pure reason alone we cannot attain a knowledge of the nature of the material universe. Finally, Kant takes up the tlieological idea, the idea of God, and criticizes the methods and arguments of rational theology. The speculative basis of our belief in tlie existence of God is unsound, he says, because the proofs brought forward to sup- port it are not conclusive. St. Anselm's ontological argument tries to establish an existential proposition without reference to experience; it confounds the order of things with the order of ideas. The cos- mological argument carries the principle of causality beyond the world of sense-experience, where alone it is valid. And the physico-theological argument from design, while it may prove the existence of an intelli- gent designer, cannot establish the existence of a Supreme Being. Kant, of course, does not deny the existence of God, neither docs he deny the immor- tality of the soul or the ultimate reality of matter. His aim is to show that the three ideas, or, in other words, speculative reasoning concerning the soul, the universe, and God, do not add to our knowledge. But, although the ideas do not extend our experience, they regulate it. The best way to think about our ciinscious states is to represent them as inhering in a substaiitiMl subject, about which, however, we can know nothing. The best way to think of the external world is to represent it as a multiplicity of appear-
