# A Brief History of Modern Philosophy/Book 5

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FIFTH BOOK
IMMANUEL KANT AND THE CRITICAL PHILOSOPHY
We have found investigations into the nature of knowledge as early as the philosophers of the Renaissance and in the great system builders. But they were nevertheless decidedly under the spell of the constructive tendency. As a result of the English empirical philosophy regarding the investigation of knowledge as the distinctive problem of philosophy, we have the extreme statement of the problem by Hume. It was this statement of the problem that furnished the occasion which led Kant to undertake a comprehensive investigation of the conditions and presuppositions of our knowledge and of our mental functions in general. Such an investigation constitutes the task of what he has called the Critical Philosophy. The critical philosophy has nothing to do with a theory of the evolution of knowledge, in the modern sense of the word. Its distinctive task is to discover the necessary principles which must be presupposed—howsoever human nature may be constituted—if a mental function, no matter whether it be cognition, aesthetic or ethical evaluation, or religious trust, is to attain any valid results. It investigates the conditions of the validity of knowledge, not those of its origin. The success of and the purely scientific element contained in this philosophy consists in its penetrating beneath the finished products and results of the human mind to their efficient causes. Just as we can only understand a man's real nature by penetrating beneath his outward acts to his real character, so likewise the only way ​to understand the phenomena of mental life is to penetrate to its original sources.—By founding the critical philosophy, in this understanding of the term, Kant defined the problem and method of the science of mind. The entire product of the nineteenth century in the department of the mental sciences is based upon the view-points which he has marked out.
According to Kant's theory, primitive human thought is dogmatic. Man begins with an implicit confidence in his intellect and he believes himself capable of solving all problems. He wishes to comprehend and coördinate everything. It is this desire that leads to the dogmatic systems, which proceed from the demand for unity so deeply imbedded in human nature. But eventually, when disillusionment supervenes, and the systems are found to contradict each other, there arises a tendency towards sceptical reflection. The third step however is the specific investigation of knowledge or the understanding, i. e. critical reflection. It is this endeavor, at once the sign of philosophic maturity and self-limitation, that Kant wishes to introduce.
The life of the thinker who bequeathed this profound thought to the world was confined within narrow circles, but it is a life of simple majesty. Immanuel Kant was born of poor artizan parents at Königsberg on the 22d of April, 1724. His parents were moderate pietists, and the mother especially exerted a profound influence upon the son. At the University in Königsberg he studied the Wolffian philosophy and the Newtonian physics. Through the former he became acquainted with the dogmatic method of philosophy, and in the latter he discovered a pattern of exact empirical science. After having spent several years in various families of the nobility in East ​Prussia as private tutor, he habilitated as Privatdozent at the University, in which capacity he labored for a long period with pronounced success. Not until 1770 did he receive an ordinary professorship. He never left his native province of East Prussia. He devoted his whole life to the elaboration of his works and to his academic instruction. Notwithstanding this however he participated actively in the social life of Königsberg and had the reputation of being a most agreeable companion. He belongs to the period of the enlightenment, but he regarded "enlightenment" as a process, a problem, rather than as a finished product. And finally, when his critical principle led him into profound depths, unknown to the ordinary enlightenment, he possessed a sense for the sublime in harmony with the conception of the aesthetic, ethical and religious which furnished the guiding principle of his mental life. In his old age, under the clerical reaction which followed the death of Frederick the Great, he suffered persecution. The publication of an essay on religious philosophy in 1793 brought forth a royal rescript against him with a threat of severer measures in case he persisted in the same tendency. Kant replied with the declaration that he would thenceforth neither speak nor write anything whatsoever on religious matters. He did not renew his activities in the philosophy of religion until the beginning of a new administration when he published the whole of the controversial proceeding (in the preface to the Streit der Facultäten, 1798). His last years present a case of the gradual disintegration of a mighty spirit. He apparently became a victim of dementia senilis. Isolated moments of mental brilliance are the only reminders of his former greatness. He died on the 12th of February, 1804.
A. The Theoretical Problem
1. Kant's philosophical reflections matured very slowly. There are two distinct periods of development, in his theoretical writings, before the appearance of his masterpiece; the first extends from 1755 (the year of Kant's habilitation) to 1769, the second from 1769 to 1781 (in which latter year his masterpiece appeared).—In describing the historical development of the Kantian philosophy (both as respects the theoretical as well as the practical problems) the author of this text book follows his essay on Die Kontinuität im philosophischen Entwicklungsgange Kant's (Archiv für Gesch. der Philos., VII, 1894).
a. The dominant characteristic of Kant's first period is the firm conviction that an all-pervasive uniformity of nature rigidly determines the phenomenal universe. His famous hypothesis of the evolution of our solar system is elaborated in his Allgemeine Naturgeschichte und Theorie des Himmels (1755). Newton had declared that a scientific explanation of the origin of the solar system is impossible. But Kant now shows that such an explanation is possible. He starts with the assumption of a rotating nebulous sphere, and then deduces the logical consequences according to the known laws of nature. He furthermore regards the denial of nature's capacity to evolve order and purpose from its own inherent laws as an erroneous presupposition. He discovers the proof of deity in the very fact of the uniformity of nature itself.—Kant elaborated this theory more fully in the essay Einzig möglicher Beweisgrund einer Demonstration Gottes. Whilst he had even then already lost confidence in the validity of the traditional "proofs" of the existence of God, he at the same time found a basis for his religious conviction in the ​ultimate postulate of all real science—the postulate of the uniformity of nature. He stood quite close to Spinoza in this respect without being aware of it.
Kant's mind was likewise occupied with various other problems during this period. His conclusion concerning the distinction between philosophy and mathematics is noteworthy, namely, that philosophy cannot create its concepts as mathematics does. It derives its concepts from experience. Hence, inasmuch as experience is never universal, philosophy is limited to imperfect concepts. The concept of soul, for example, is an imperfect concept; experience furnishes no warrant for speaking of a psychical substance. In the ingenious brochure, Traume eines Geistersehers, erlaütert durch Traüme der Metaphysik (1766), Kant shows, partly in satire, how easy it is to construct a system of the supersensible world. The only requirement is a naive implicit confidence in our concepts as complete and final.
The concept of causality is another example of an incomplete concept. How can the analysis of a given phenomenon reveal the necessity of another phenomenon? But the concept of causality assumes precisely this necessity! K ant therefore (even in the essay: Versuch den Begriff der negativen Grösse in die Weltweisheit einzuführen, 1762) approaches the problem of causality in precisely the same form in which it had been stated by Hume. Kant's later remark that it was David Hume that roused him from his dogmatic slumbers, with its evident reference to Hume's criticism of the concept of causality, would indicate that this awakening took place as early as 1762. (Students of Kant differ widely on this point however.) It is impossible to describe the years in which Kant was occupied with the study of the causal concept and ​The Dreams of a Ghost-seer, as spent in "dogmatic slumber."
b. Kant is led to the first step from his inquiring, sceptical attitude towards criticism by the discovery that space and time, with which the exact natural sciences operate, are not real objects or attributes in the absolute sense; but schemata (schemata coordinandi) which are abstracted from the forms in which our sensations are arranged. Space, which Newton regarded a divine sense, thus becomes a human sense (De mundi sensibilis atque intelligibilis forma et principiis, 1770). He makes the discovery that many propositions which we regard as objective only express the conditions under which we perceive or conceive the objects. For the time being he applies this observation only to space and time as the forms of sense-perception. This was nevertheless the discovery of the fundamental thought of the critical philosophy. Kant had thus already discovered the theoretical method which he afterwards called the Copernican method. Just as our perception of the rotation of the firmament around the earth is due to our position in the universe, so, according to Kant, it is likewise due to our method of sense perception that we apprehend things under the relations of time and space. This explains therefore—and this is the essential matter so far as Kant is concerned—how it happens that pure mathematics, which is after all a purely intellectual science, can be valid for every possible sense-perception. We experience everything in time and space, and everything must therefore conform to the mathematical laws of time and space.
Kant was still of the opinion that the understanding could grasp the absolute nature of things. But he soon saw that the Copernican principle must likewise apply to ​the understanding. His letters and notes enable us to follow the gradual development of this deeper insight. We are active in the operations of our own thought, i. e. we act in a manner peculiar to our mind; but how can the products of our own mental activity retain their validity when applied to the perceptions which are objectively produced?—As to the nature of this mental activity, an investigation of the fundamental concepts of our understanding, especially the causal concept, reveals the fact that the understanding is likewise a uniting, synthetizing faculty like sense-perception. The uniting principle (Hume's), which was the stumbling-block of Kant's English predecessor, now became Kant's fundamental presupposition of knowledge. He could now say of the fundamental concepts of the understanding (categories), after the analogy of what he had previously said of the forms of intuition: Knowledge exists only when what is given (the matter) in the forms of our thought is united. The concept of synthesis is therefore the fundamental concept of all knowledge and the profoundest thought of the Kantian philosophy. This constitutes Kant's real discovery, which will justify its value, even if Kant's particular theories are to a considerable degree subject to criticism. We must apply his own method in the study of Kant. We must penetrate the finished forms in which his philosophy is cast and discover their primary principles—realities.
According to his own statement, Kant wrote out the results of his reflections covering a period of twelve years quite hastily. His chief work, Kritik der reinen Vernunft (1781), is therefore a very difficult book.—In presenting its contents we shall follow a clearer order than that given by Kant himself. ​2. Kant distinguishes a subjective and an objective deduction in his investigation of the problem of knowledge.
a. It is the business of subjective deduction to discover the forms of our intuition and reflection. These forms represent what is constant and universal,—that which is capable of maintaining its identity, even though the qualitative content, the matter, changes. They are discovered by a psychological analysis which distinguishes between the changeable and the permanent. In this way we discover extension (space) and succession (time) as constant elements of sensory intuition, magnitude and causality as constant elements of thought. The Forms of intuition are forms of our receptivity. As a matter of fact they too are a kind of synthesis, a combining together; but at this stage our own activity does not yet attain the prominence that it does in thought; here the only concern is the arrangement of the sensations in immediate intuition. We develop a higher level of activity whenever we place these intuitional images in relation to each other. This function is more fully conscious than the involuntary process of intuition. Kant calls it apperception. Whenever we pass from a given spatial or temporal intuition to another, we are trying to affect our own inner unity, in the fact that we combine together the antecedent and consequent in a definite manner. Thus, e. g. I know a line only when I draw it, i. e. when I combine its several parts according to a definite law. Or, e. g. I know a fact, e. g. the freezing of water, only when I am in position to combine the antecedent state (the water in liquid form) with its consequent according to a definite law.
Kant believes that he has thus discovered a method which proves the necessity of a certain number of ​concepts of the understanding (categories). He says the function of the understanding is judgment; every judgment consists of a combination of concepts. There must therefore be as many different categories as there are kinds of judgments!—He thus discovers, on the basis of the traditional logic (of course somewhat modified by himself), twelve categories, neither more nor less. This was certainly a profound illusion. For the customary classification of judgments is logically untenable, it is at least impossible to justify the inference from them to different kinds of fundamental categories.
Kant divides the twelve categories, which we will not here repeat, into two classes: mathematical and dynamic; the concept of magnitude and the concept of causality might be regarded as representative of these two classes. All our judgments express either a relation of magnitude (greater or less) or a relation of real dependence (cause and effect). The concept of continuity is common to both relations: all magnitudes arise continuously from smaller magnitudes, and cause passes continuously into effect.
We have thus far discovered two groups of forms: the forms of intuition and of the categories. But there is still a third group. We are not satisfied with simply arranging sensations in space and time, and afterwards arranging the intuitional forms which have thus arisen according to their relations of magnitude and cause. The synthetic impulse, the combining activity, is so deeply imbedded in our nature that we are constantly in search of higher unities and totalities and finally demand an absolute completion of the synthesis. This is the sphere of ideas, the forms, in which man attempts to conceive absolute unities and totalities. Kant calls the ideational faculty ​reason in its narrower significance. (In its broader significance understanding and intuition likewise belong to reason.) Those synthetic impulses together with these ideational faculties give rise to the dogmatic systems which deal with the ideas of God (as the absolute being), the soul (as substance) and the world (as absolute totality) . Kant attempts to prove, by a very artificial method, that these three are the only ideas: they are to correspond with the three forms of inference of the traditional logic.
b. Objective deduction investigates the right of applying our cognitive forms to given sensations. The fact that we are able to become conscious of the content of our intuitions and concepts does not constitute the problem. Neither does the fact that we can deduce new content from experience constitute a problem. But Kant's problem rather consists in this, namely, the fact that we are able to use our intuitional forms and categories in such a way as to form, with their help, valid judgments which are not found in experience. He expresses it in his own language as follows: How are synthetic judgments a priori possible? By analytical propositions we become aware of the content of our intuitions and reflections; by synthetical propositions a posteriori we include new content derived from experience; but synthetic propositions a priori extend our knowledge independently of our experience. The following are examples of such propositions: every perception has extensive and intensive values, and every event has a cause (or better: every change takes place according to the law of the connection between cause and effect).
According to Kant the validity of such judgments rests upon the fact that experience—in the sense of the fixed and necessary relations of phenomena—is possible only in ​case the mathematical laws and the concepts of magnitude and causality are valid for all perceptions. Only such abstract propositions as formulate the very conditions of experience are synthetic propositions a priori. Whenever we are able to discover and express the conditions of experience we come upon propositions which are propositions of pure reason, because they are based on the pure forms of our knowledge, and which must nevertheless be valid for all experience.
The whole content of experience is conceived in space and time. Hence since pure mathematics really does nothing more than develop the laws of space and time, it must be valid for every possible content of experience, every possible perception. But this demonstration likewise involves a limitation: namely, mathematics is valid only for phenomena, i. e. only for things as we conceive them, not for things-in-themselves. We have no right to make the conditions of our conception the conditions of things-in-themselves. Time and space can be conceived only from the view-point of man.
Experience not only implies that we conceive something in space and time, but likewise that we are able to combine what is given in space and time in a definite way, i. e. as indicated in the concepts of magnitude and causality. This is the only means of distinguishing between experience and mere representation or imagination. All extensive and intensive changes must proceed continuously, i. e. through every possible degree of extension and intensity, otherwise we could never be certain of having any real experience. Gaps and breaks must be impossible (non datur hiatus non datur saltus). The origin of each particular phenomenon moreover must be conditioned by certain other phenomena,—analogous to the way in which ​the conclusion of a syllogism is conditioned by the premises. In any purely subjective representations or in dreams, images may be combined in every variety of ways; we have experience however only when it is impossible to permit the members of a series of perceptions to exchange their places or to pass from one perception to another by means of a leap. In my mind I can at will, e.g. conceive of a house being built from the roof downward or from the foundation upward; but in the case of the actual construction of a house there is but a single possible order of succession. Wherever there appear to be gaps in the series of perceptions we assume that further investigation will discover the intervening members. This demonstration of the validity of the categories of magnitude and causality likewise involves a limitation: The validity of the categories can only be affirmed within the range of possible experience; they cannot be applied to things which from their very nature cannot become objects of experience. Experience is the empirical synthesis which furnishes validity to every other synthesis.
The principles of demonstration by which we obtain our results when dealing with the forms of intuition and the categories are inapplicable to the realm of ideas. The ideas demand an unconditionally, a totality, finality; but experience, which is always limited, never furnishes any such thing. Neither God, nor the soul (as substance), nor the universe (as an absolute whole) can be given in experience. There is here no possibility of an objective deduction. It is impossible to construct a science of ideas.
When Kant bases the real significance of the rational sciences upon an analysis of the conditions of experience, it must of course be remembered that he uses the concept of experience in its strict sense. Experience consists of ​the fixed and necessary relation of perceptions. But in this sense experience is an idea (in Kant's meaning of the term) or an ideal. We can approach this ideal to infinity, but it was a piece of dogmatism when Kant here failed to distinguish between the ideal and reality. Kant had not, as he believed, solved the problem propounded by Hume; for the thing concerning which Hume was skeptical was just the matter as to whether any experience in the strict sense of the term really exists.—This dogmatic tendency is peculiarly prominent in Kant's special works, especially in his Metaphysische Anfangsgrunden der Naturwissen-schaft (1786).—Kant's chief merit consists in referring all knowledge to synthesis and continuity. These fundamental principles enable us to anticipate experience. But all anticipations are only hypotheses.
3. As we have observed, the demonstration of the real validity of abstract knowledge (of pure reason) is closely related to the limitation of this validity. Kant states this as follows: We know only experiences, but not things-in-themselves. Whenever he expresses himself concisely, he calls the concept of the thing-in-itself an ultimate concept or a negative concept. In this way he gives expression to the permanently irrational element of knowledge. Speaking exactly, the concept of the thing-in-itself indicates that we cannot deduce the matter of our knowledge from its form. For Kant however the concept of the thing-in-itself imperceptibly assumes a positive character. The thing-in-itself is regarded as the cause of phenomena (especially in reference to the matter, but likewise also in reference to the form). Here (as F. H. Jacobi was the first to show) Kant falls into a peculiar contradiction; he has limited the real validity of the concept of causality to the realm of experience (in which the thing-in-itself can never be ​present) and then conceives the thing-in-itself as cause!— Here again we discover a remnant of dogmatism in Kant.
4. Kant proves the impossibility of constructing a science of "Ideas," both by the fact that ideas contain none of the conditions of experience (as is the case with the forms of intuition and the categories), and by means of a criticism of the attempts which have been made to establish such a science.
a. Criticism of speculative (spiritualistic) psychology. There is no justification for concluding from the unity of psychic life, which manifests itself in synthesis, the fundamental form of consciousness, that the soul is a being which is distinct from the body or a substance. Synthesis is only a form, which we are not permitted to regard as a separate substance. It is impossible for psychology to be more than a science of experience. There is no ground for interpreting the distinction between psychical and physical phenomena as a distinction between two entities: It is possible indeed that one and the same essence should form the basis of both kinds of phenomena.
b. Criticism of speculative cosmology. Every attempt at a scientific theory of the universe conceived as a totality is ever and anon confronted with contradictions. Our thought here culminates in antinomies; the universe must have a beginning (in space and time), else it were not a totality. But it is impossible to conceive the beginning or the end of space and of time, because every place (in space and in time) is thought in relation to other places.— Furthermore the world must consist of parts (atoms or monads) which are not further divisible, otherwise the summation of the parts could never be complete. But everything conceivable is divisible; we can think of every body as divided into smaller bodies.—The series of causes ​must have a first member if the universe is to be regarded as a complete system, and if a complete causal explanation of particular phenomena shall be possible. But the assumption of a first cause is in conflict with the law of causality, for this cause would itself have no cause, and at what moment should it begin its operation?
According to Kant the only way to avoid these antinomies is to distinguish between phenomenon and the thing-in-itself and limit the validity of our knowledge to phenomena. We meet with contradictions the moment we attempt to apply our concepts to the things which transcend our circumscribed experience. Kant therefore regards the antinomies as a demonstration of his theory of knowledge.
c. Criticism of speculative theology. Reflective thought aims to find in the concept of God an absolute resting- place for all its effort. This concept is supposed to contain the ground of the concepts of soul and universe. In it knowledge would attain its ideal: all ideas would be referred to a single idea which in turn contains the ground of its existence within itself and hence implies nothing beyond it! According to Kant the concept of God is fully justified as an ideal; but we must not confuse an ideal of knowledge with knowledge actually attained. The traditional arguments for the existence of God however rest upon such a confusion of terms.
The most popular argument rests upon the adaptation of nature and thence infers the existence of an all-wise, all-loving and all-powerful Creator (the physico-theological argument).—But by what right do we presuppose that the order and adaptation of nature should not be explainable as the effects of natural causes operating according to natural laws? And at any rate this argument can only lead to ​the assumption of an architect or governor of the universe, not to that of a creator.
The cosmological argument goes into the matter more profoundly: the universe must have a cause (both as to its matter as well as to its plan).—But the law of causality leads only from one member of the causal series to another —it only furnishes causes which are in turn conditioned, i. e. effects, and hence never establishes the assumption of an unconditioned, necessary being. In the case of every existing thing, even the highest, it always remains not only possible but necessary to inquire: Whence doth it come?
The ontological argument, if it were tenable, is the only one that would lead to the desired goal. It is also the tacit presupposition of all the other arguments. This argument proceeds as follows: to think of God as nonexistent were a contradiction, because He is the perfect being and existence belongs to perfection!—But existence or being is a predicate which differs from all other predicates. The concept of a thing does not change because the particular thing does not exist. My concept of a hundred dollars is the same, no matter whether I possess them or only think of them. The problem of existence is independent of the problem of the perfection of the concept. And, as the investigation of the categories has shown, we have but a single criterion of existence or reality: namely, the systematic uniformity of experience.
B. The Ethico-Religious Problem
1. There is a sense in which Kant's ethical ideas develop along parallel lines with his ideas of theoretical knowledge. Rousseau's influence evidently affected him on this point at two different periods with telling effect. Kant declares, in an interesting fragment, that Rousseau ​taught him reverence for mankind, to ascribe a certain dignity to all men which is not merely based on the degree of their intellectual culture. He had previously been an optimist whose basis was an intellectual and spiritual aristocracy. And in addition to Rousseau, Shaftesbury, Hume and especially Hutcheson likewise influenced him at this period. During the sixties Kant bases his ethics on the sentiment of beauty and the dignity of human nature. (Beobachtungen über das Gefühl des Schönen und des Erhabenen, 1764.) Even here Kant already emphasizes the necessity of fundamental principles of morality; they are however only the intellectual expressions of the content of the sentiments: "The fundamental principles are not abstract laws, but the consciousness of an affection that dwells in every human breast … of the beauty and dignity of human nature."
Kant afterwards abandoned this identification of ethics with the psychology of the affections. In his Essay of 1770 he declared that it is utterly impossible to base moral principles on sentiment, i.e. empirically. It is also evident, from a fragment discovered by Reicke, that at the period during which he was engaged with the Critique of Pure Reason he based the ethical impulse on the self- activity which we exercise in our striving for happiness. The matter of happiness is empirical, but its form is intellectual, and the only possibility of realizing our freedom and independence rests upon maintaining the constant harmony of our will with itself. Morality is liberty under a universal law which expresses our self-consistency. Even here Kant's ethics attains that purely formal character which is so peculiar to it. In ethics as in epistemology he regards the form as the constant factor in contrast with its ever-varying content.
​But in the fragment just cited Kant's ethics was still individualistic: The moral law demands only that the individual be in harmony with himself. The specifically Kantian ethics springs from an expansion of this principle. He elaborates it in the Grundlegung zur Metaphysik der Sitten (1785) and the Kritik der praktischen Vernunft (1788). Here he formulates the moral law as follows: Act according to the maxim that you could at the same time will that it might become a universal law!—The viewpoint is therefore no longer individualistic, but social. His elaboration of the theory of knowledge evidently affected his ethics at this point. The fundamental moral law must be quite as universal and objective as the theoretical fundamental principles, as e. g. the principle of causality! But there are other theoretical motives likewise here in evidence.
In the interval between the fragment just cited (1780) and the first draft of the ethics (1785) another noteworthy essay appeared, namely, Idee zu einer allgemeinen Geschichte in weltbürgerlicher Absicht (1784), in which Kant shows that the only viewpoint from which history is comprehensible and of any value is from that of the human race as a whole, but not from that of the individual citizen. Reason is an evolutional product of the process of history. The antagonism of interests brings the capacities of man to maturity, until he finally organizes a society in which freedom under universal laws is possible. And it is only then that genuine morality becomes possible! Kant observes that Rousseau was not wholly in error in preferring the state of nature, so long as this stage has not been reached. —It is evident that, from the viewpoint of history, the moral law which Kant formulated in 1785 contains a sublime anticipation. The individual citizen is expected to ​regulate his actions here and now, precisely as all actions shall finally be regulated in that ideal society. Morality, like history, is likewise incomprehensible from the viewpoint of the individual.—Kant returns to this theory two years later (1786 in the essay on Muthmasslicher Anfang der Menschengeschichte). Civilization and nature are contradictory principles (so far Rousseau was right) "until perfect art becomes nature once more, which is the final aim of the moral determination of the human race." Kant therefore arrived at this definitive ethical theory by the historical or social-psychological method, and Rousseau's conception of the problem of civilization influenced him at this point, just as it did at an earlier stage of his ethical reflection.—But in the mind of Kant that sublime anticipation appears with such ideality and absoluteness that he regarded the fundamental moral law as a manifestation from a super-empirical world and he forgot his historical and psychological basis. (Cf. the author's essay: Rousseau's Einfluss auf die definitive Form der Kant'schen Ethik, in Kantstudien, II, 1898.)
2. In the first draft of his ethics (1785) Kant discovers the fundamental moral law by means of an analysis of the practical moral consciousness. That action alone is good which springs from pure regard for the moral law. Neither authority nor experience can be the source of this sense. Moral principles reveal the inmost, supersensible nature of our volition, and neither psychology nor theology can here furnish the basis. The fact is the more evident in that there are elements in human nature which impel us in directions which are contrary to the moral law. The moral law manifests itself in opposition to these empirical and egoistic tendencies in the form of duty, an unconditional command, a categorical imperative. The ​distinctively moral element appears most clearly in cases where duty and inclination stand out in sharp contrast. Kant even says in a certain place that a state of mind in which I follow duty even though it is in conflict with my purposes is the only one which is really good in itself.
The moral law must be purely formal. Every real content, every purpose would degrade it to the level of the empirical and hence to the material. The moral law can do nothing more than indicate the form of the fundamental principles which our actions are intended to express,— that is to say, that these fundamental principles are capable of being based on a universal principle of legislation in such manner as to enable all rational beings to obey them under similar circumstances. I must, e. g. return borrowed property even though no one knows that it does not belong to me; because the contrary course will not admit of generalization, and in that case no one would make a loan to another. Kant however here clearly presupposes that man is a member of society. This maxim is therefore not purely a priori. He likewise realizes the need of a more realistic formulation of the maxim and the necessity of a real object of human action. The highest object can be given only through the moral law, and Kant discovers this object in the very dignity which every man possesses in the fact of being capable of becoming conscious of the moral law. From this he deduces the principle: "Act so as to treat humanity, in thyself or any other, as an end always, and never merely as a means!"
The moral law is not objective, but deeply imbedded in the nature of man and identical with the essential nature of volition. Law and liberty are not separate concepts. They express only the autonomy of man viewed from opposite sides. As an empirical being man is subject to ​psychological laws, but as a rational being he is elevated above all empirical conditions and capable of originating a series of changes absolutely. But man possesses this capacity only as an "intelligible character," as a "thing-in-itself." And since things-in-themselves can never be given in experience, it is impossible for intelligible liberty and empirical necessity ever to conflict with each other. Kant here introduces a positive use of the concept of the thing- in-itself.
Kant elaborated the special problems of ethics in his Rechtslehre and his Tugendlehre. Both works appeared in 1797 and bear the impress of old age.—Right, according to Kant, consists of the aggregate conditions under which the will of the individual can be united with the will of another according to a universal principle of liberty. As a matter of fact man's only original right is liberty, i. e. immunity from the arbitrary demands of every other individual in so far as it can obtain together with the liberty of others according to a universal law. Even though Kant makes a sharp distinction between the Right and the Moral (Legality and Morality), he nevertheless regards our obligation to regulate society as far as possible according to principles of Right to rest upon a categorical imperative.
In the Theory of Virtue he finds the highest duty in the realization of the dignity of man, which is based on autonomy and consists in the complete development of personal qualities. To be useless and superfluous is to dishonor humanity in our own person. Besides personal perfection the happiness of others is a matter of fundamental importance. The perfection of others on the other hand can only be realized through their own efforts; and we provide for our own happiness even through a natural instinct.
​3. Kant aimed to establish the pure autonomy and spontaneity of the moral sense, and especially as independent of all theological presuppositions. But he was nevertheless convinced that religion and morality are vitally related. He finds the transition from morality to religion to rest on the fact that man is destined to realize the unconditional moral law in the empirical world, i. e. in the world of finitude, limitation and conditionality. Ideal and reality here appear in sharp contrast to each other, which gives rise to a demand for harmony between liberty and nature, virtue and happiness, and it is just because experience offers no guarantee, that religious postulates, which contain the conditions of such a harmony, are formulated. Besides the freedom of the will previously cited, there are according to Kant two additional postulates: viz. the immortality of the soul and the existence of God. Kant is convinced that these postulates reveal a universal human need. Faith is the natural consequence of the sentiment of morality, even though faith is not a duty.
The possibility of faith rests upon the fact that knowledge is limited to phenomena. The native element of the dogmas of faith is the thing-in-itself. But these dogmas add nothing to our knowledge. This follows even from the fact that our intellectual and intuitional forms do not pertain to the thing-in-itself. Religious ideas are nothing more than analogies or figures of speech. Kant even goes so far as to say that if the anthropomorphisms are carefully discarded from the psychological attributes ascribed to God, nothing remains but the empty word.
This fact, which even applies to the ideas of natural religion, is still mere pertinent to the ideas of positive religion. In his treatise on Religion innerhalb der Grenzen der ​blossen Vernunft (1793) Kant shows that important ethical ideas are hidden within the Christian dogmas. In the dogma concerning sin he discovers the experience of an inclination, deeply imbedded in human nature, which strives against the moral law; which he calls "radical evil." Kant regards the Bible story of the Fall as a subjective experience on the part of each individual, not as an historical event. So is the Bible story of the suffering Christ likewise experienced by every serious human being; regard for the moral law gives rise to a new man who must endure the suffering due to the constant opposition of the old man of sensual inclination.—The significance of a purely historical or "statutory" faith is only provisional; but we respect "the form which has served the purpose of bringing a doctrine, the acceptance of which rests on tradition,—which is irrevocably preserved in every soul and requires no miracle,—into general influence."
4. Kant maintains a sharp antithesis between the world of experience and things-in-themselves both in his theory of knowledge and in his ethics. In fact, his whole philosophy is characterized by these sharp antitheses. This was necessary to his purpose, if he would demonstrate the validity of knowledge and the unconditionality of ethical ideals. But the question must naturally arise— even in consequence of the critical philosophy—Must not even these distinctions and antitheses be ascribed to the method of our human understanding? The fact that this point also occurred to his mind with more or less definiteness is a splendid testimony to Kant's profound critical acumen. He felt the need before concluding his reflections, of investigating whether there might not be viewpoints which—more directly than the religious postulates—would transcend these profound antitheses. He thus ​discovers certain facts which show us how existence by virtue of its own laws and even our ethical ideals become matters of our knowledge. There are two such facts: the one is of an aesthetic nature, the other biological (Kritik der Urtheilskraft, 1790).
In the phenomena which we call beautiful and sublime the object inspires in us a sense of disinterested satisfaction. In the case of the beautiful this rests on the fact that our intuitional faculty or our understanding is induced to harmonious cooperation, in that the parts of a phenomenon are readily and naturally combined into a single unit. Kant places special emphasis on the pure immediacy and involuntariness of the impression of beauty,—what he calls free beauty (e. g. the beauty of a flower, of an arabesque, of a musical fantasy). He does not regard the "secondary" beauty presupposed in the concept of an object (e. g. the beauty of man as such) as real beauty.—In contemplating the sublime our faculty of comprehension is overwhelmed and the sense of self subdued in the consciousness of being confronted by the immensity, the immeasurable in content and energy; but even in this very vanquishment, the consciousness of an energy superior to all sensible limitations arises in our consciousness: the consciousness of ideas and of the moral law as transcending all experience. The really sublime, according to Kant, is not the object, but the sentiment to which it gives rise.
Just as we behold the activity of Being in harmony with our spiritual dispositions in the beautiful and the sublime, even so the genius acts his part as involuntarily as a process of nature, and nevertheless produces works which have the value of patterns or types. Genius is a talent by means of which nature furnishes rules of art,—it is typical originality.
​Organic life presents an analogy to the beautiful, the sublime, and the ingenious. Nature employs a method in the organic realm for which we really have no concept. Here we do not discover a being originated by the mechanical articulation and interaction of parts; nor have we the right, scientifically, to assume an antecedent plan according to which the parts are afterwards combined (as in the case of human architecture). The organism is therefore unexplainable either teleologically or mechanically. But perhaps the antithesis between the mechanical and the teleological explanations of nature rests merely on the peculiarity of our knowledge. Our understanding proceeds discursively, i. e. it proceeds from the parts to the whole, and if the parts are to be regarded as defined from the viewpoint of the whole, we are obliged to apply the anthropomorphic analogy with human purposes. But in pure being the same regulation which provides for the causal unity of things might perhaps also account for the possibility of the origin of organic forms capable of adaptation. It might be that the principles of mechanism and of teleology are after all identical in the unknown grounds of nature.
The same might be true also of the antithesis of pure reason which formulates natural laws, and the practical reason which propounds ethical ideals. Such being the case it would follow that it is one and the same principle which is revealed in the laws of nature and in the principles of ethics!
Here Kant reverts at the conclusion of his career, to a theory which had engaged him considerably during his early life (Allgemeine Naturgeschichte und Theorie des Himmels. Einzig moglicher Beweisgrund), and which ​tainly had never left him. He suggests the possibility of a monistic theory, which, according to his conviction, was incapable of scientific elaboration.
C. Opponents and First Disciples
If Kant himself felt that the stupendous critical task made it necessary to appeal to a fundamental unity behind the variety of distinctions, such demand must necessarily become even more insistent to independent thinkers who assumed a critical attitude to his own investigations. Independent disciples, if they had seriously studied the doctrines of the master, must likewise have felt the need of a greater unity and harmony. The difference between the opponents and the disciples consists in the fact that the former assumed a purely polemical attitude, whilst the latter endeavored to forge ahead to new viewpoints on the basis of the critical philosophy; the former oppose the necessary totality of life and faith to philosophical analysis, whilst the latter seek to realize a new idea of totality by means of a thorough analysis.
1. Foremost among the opponents, stands John George Hamann (1730-1788), "The Wise Man of the North," who was one of Kant's personal friends. After a restless youth he settled in Königsberg in the office of Superintendent of Customs. His external circumstances were poor and he experienced profound mental struggles. He was a foe to every kind of analysis because of a morbid demand in his own nature for a complete, vital and undivided spiritual reality. He finds the ground of religion in our total being and it is far more comprehensive than the sphere of knowledge. The life of pure thought is the most abstract form of existence. Hamann refers to Hume as not having been refuted by Kant (the Prussian Hume). ​In harmony with Giordano Bruno he thinks existence consists of a coincidence of opposites (coincidentia oppositorum), which are compatible with life, but in reflective thought remain forever incompatible. This explains the futility of analysis. In direct antithesis to Kant he holds (in the posthumous treatise Metakritik über den Purismus der reinen Vernunft) that reason, apart from tradition, faith and experience, is utterly helpless. He directs his attack more particularly against Kant's distinction between matter and form, intuition and reflection. What nature has joined together man must not put asunder!
John Gottfried Herder (1744-1803) likewise emphasizes the helplessness of reason: It is a product, not an original principle. He makes the racial character of poetry and religion prominent, regarding them as the immediate products of the human mind, in contrast to clear conception and volitional conduct. He extols the ages in which the mental faculties operated in unison rather than in isolation from each other, in which poetry, philosophy and religion were one. He aimed to penetrate behind the division of labor in the realm of mind. During the sixties he was an enthusiastic student of Kant, whom he attacks rather indirectly in the Ideen zur Philosophie der Geschichte der Menschheit (1784-1791), which is his most important work, more directly in his later, less significant treatises (Metakritik, 1799, Kalligone, 1800). As opposed to Kant, he denies the opposition between the individual and society. The individual is identified with the entire race by innumerable unconscious influences, and his inmost being is modified by historical development. On the other hand the goal of history is not alone determined by the race as a whole but likewise by the individual. Herder was no less opposed to the distinction between mind and nature, ​God and the world, than to the sharp distinction between the individual and society, or between the conscious and the unconscious. God can no more exist apart from the world than the world can exist apart from God, and, like his friend Goethe, he was an admirer and exponent of Spinoza, to which Lessing referred in the famous conversation with Jacobi. His ecclesiastical position did not prevent him from expressing his thoughts freely and courageously. (Gott, 1787.) On this point he disagreed with his friends Hamann and Jacobi, notwithstanding their common emphasis of the total and indivisible life.
Friedrich Heinrich Jacobi(1743-1819), the third member of this group, as already observed, exposed the contradiction resulting from the Kantian theory of the "thing-in-itself" (David Hume über den Glauben, oder Idealismus und Realismus, 1787). Like Hamann and Herder, he likewise fails to find in the Kantian philosophy, and in all philosophy for that matter, the complete, total, undivided unity which can only be found in life and in unmediated faith. He contends that philosophy, if it is to be consistent, must annul all distinctions, combine everything into a single series of causes and effects, and thus not only the perfect and the vital, but even all originality and individuality, would be annulled. He used this argument in his Briefen über Spinoza (1785) against the philosophy of the enlightenment. In his David Hume he used the same argument against Kant, and later he made similar objections to Fichte (Jakobi an Fichte, 1799) and Schelling (Von den göttlichen Dingen, 1811). He regards even direct perception a miracle, since it is utterly impossible to furnish any demonstrative proof of the reality of the objective world. We are born into faith. Jacobi defends the rights of the individual ​both in the realm of morals and of religion. It is perfectly right for a beautiful soul to be guided by the affections, even though it should thus contradict abstract moral law.
2. The Kantian philosophy was first introduced into wider circles through the Briefe über die kantische Philosophie (1786) by Karl Leonhard Reinhold (1758-1823). Reinhold had become a monk in his early youth; but when the conflict between his rationalistic philosophy and the Catholic faith became too strong, he fled the cloister, became acquainted with the Kantian philosophy at Weimar and was shortly afterwards called to a Professorship at Jena (later at Kiel) . Jena now became the center of the philosophical movement inspired by Kant. In contrast to Kant’s multiplicity of distinctions and forms Reinhold proposed the derivation of everything from a single principle as the true ideal of philosophy (Versuch einer neuen Theorie des menschlichen Vorstellungsvermogens, 1789). He deduced this principle from the postulate that every idea sustains a twofold relation, to a subject as well as to an object. Consciousness, as a matter of fact, consists of such a relationship. That which Kant called Form is that element of an idea by means of which it is related to the subject. It is necessary to assume a thing-in-itself, because it is impossible for the subject to produce the object. The fact that he conceived the thing-in-itself as something entirely distinct from consciousness subjected Reinhold to a contradiction similar to that of his master. This contradiction is clearly elaborated in G. E. Schulze’s Aenesidemus (1792).
The clearest exposition of the error resulting from postulating the thing-in-itself as a positive concept however is by Salomon Maimon (1754-1800). The thing-in-itself is intended to be the cause of the matter of our knowledge,​—but we never discover any absolute, i. e. entirely unformed matter, in our consciousness, and it would therefore be impossible even to inquire concerning the cause of the matter! The pure matter (pure sensation) is an "idea" like the pure form, the pure subject.
Maimon, the Lithuanian Jew, following the example of Reinhold in quitting the Catholic cloister, abandoned his native village with its limitations and poverty, in order to satisfy his intellectual hunger in Germany. Kant admitted that Maimon was the man who best understood him; but the venerable master was nevertheless dissatisfied with the criticisms and corrections offered by his brilliant disciple.
Maimon saw clearly that the mere reference to the conditions of experience is not the solution of Hume’s problem: for what Kant calls experience, the permanent, necessary coherence of impressions, is the very thing that Hume denies. By experience Hume understands nothing more than impressions. That which is given in experience is never anything more than a succession of impressions, and it is useless to appeal to the categories, for they are nothing but rules or ideas used in our investigations. The concept of causality, e. g., enables us to attain the highest possible degree of continuity in the series of our impressions.
It is not reason that impels us to transcend experience, but the imagination and the desire for completeness. These are the motives that give rise to the ideas (in the Kantian sense), to which we afterwards ascribe objective reality. It is not the objects which are believed to exist on these grounds, but rather the constant striving after totality—which is the source of faith—that constitutes ​the highest reality. (Versuch einer Transcendentalphilosophie, 1790. Philosophisches Wörterbuch, 1791. Versuch einer neuen Logik, 1794.)
There is a close analogy between Reinhold, Maimon and Friedrich Schiller (1759- 1805). Schiller, like the others, ran away from his cramping environment (the Military school at Stuttgart). And then, after the writing of his first sentimental essays, he devoted himself more thoroughly to the Kantian literature. He greatly admired Kant’s indefatigable research and the exalted, ideal character of his ethics. But from his point of view Kant had nevertheless over-emphasized the antitheses of human nature, and severed the moral nature too completely from the actual development and ambitions of men. Duty appeared to be a kind of compelling force which man's higher nature exercises over his lower nature. Schiller therefore asserts that harmony is the highest criterion in life as well as in art. All the elements in the nature of man must cooperate in his actions. In order to be good, an act must not only bear the badge of dignity, but likewise of gracefulness. Morality is slavish as long as it consists of self-command (Über Anmut und Würde, 1793). Schiller elaborates this theory more fully in his Briefen über aesthetische Erziehung (1795) which shows a decided agreement with Rousseau’s problem of civilization (which likewise exerted a profound influence on the reflections of Kant). The important thing is to surcharge the spontaneous fullness of the natural life with the independence and freedom of human life, the devotion to everchanging circumstances with the unity of personality, the matter-impulse with the form-impulse. The solution of this problem is found in play, which is the beginning and prototype of art. It is only in ​the free play of his energies that man acts as a totality. The æsthetic state is therefore the highest perfection of culture: it is at once the end and the means of development, which transcends all coarseness and all harmony.