KANT, IMMANUEL. – Philosopher, born in Königsberg, capital of East Prussia, on 22 April 1724, died there on 12 February 1804. He is unanimously regarded as the greatest thinker of the modern age, indeed with him a new epoch in philosophy begins. His life was almost devoid of external events: K., who lived almost always in his native city, remained estranged from the great historical events of his time. The “pietism” (q.v.) of his mother (his father was a saddler) exerted a strong influence on his spirit; the education he received at the Fridericianum College, where he completed his secondary studies, was also shaped by pietism. He subsequently attended the Faculty of Philosophy at Königsberg, where the teachings adhered to the methods of Wolff’s rationalism, a disseminator of the Leibnizian system but with a greater emphasis on the “Enlightenment” dogma of the supremacy of reason as the sole source of truth. During his university years, K. also devoted himself to the study of mathematics and physics, and above all to Newton’s physics, which he regarded as the model of human knowledge. After completing his studies and serving as a private tutor in noble households, he embarked on an academic career. In 1755, he obtained his habilitation in philosophy; after two failed attempts (in 1756 and 1758) to secure a full professorship in philosophy, he finally succeeded in 1770 in obtaining the chair of logic and metaphysics at the University of Königsberg, where he taught until 1796, the year in which, due to physical and mental decline, he retired from teaching.
Of a cheerful and serene disposition, a man of few affections and friendships, meticulous almost to the point of exaggeration, and open to cultural interests, particularly scientific ones, such was the character of K. Pietist education, on the one hand, and Enlightenment influences, on the other, led him to reduce everything to the moral value of humanity and to the uninhibited knowledge of nature. K., as a man and a philosopher, lacked a profound sensitivity to the human and the divine (he is the philosopher of external experience rather than of the interior life), and thus he also lacked an authentic concept of humanity and Christianity.
Three important points must be noted in K.’s intellectual formation:
a) the pietist education that instilled in him a sense of human dignity and of the inner life, of duty fulfilled in absolute independence from any external construction or authority, reinforced by his reading of Rousseau’s works (q.v.), the critic of civilization and of rational “Enlightenment,” the defender of human nature as an intimacy and spontaneity of feeling, conscience of duty, and freedom;
b) the Wolffian-Enlightenment formation, in some respects contrasting with the former, which exalted the supremacy of reason, a principle to which K. remained ever faithful;
c) the study of physics as understood by Newton (q.v.), to which K. always adhered even when he critically elaborated the problem of knowledge. Taking these three formative elements into account—along with the strong influence of English empiricism (especially Hume)—it is already evident how K. was oriented in two directions that were not contradictory but dissenting (two paths but not one against the other): the supremacy of reason (Enlightenment-Wolff) and of physics as the model of rational knowledge (Newton), and at the same time the problem of the conditions, value, and limits of reason itself (empiricism-Hume); the supremacy of human dignity as revealed in autonomous and interior moral conscience (pietism-Rousseau). The intellectual formation contains the elements that explicitly explain the conclusion of the *Critique of Practical Reason*: “the starry heavens above me and the moral law within me,” words which, quite rightly, were chosen as the epitaph on the philosopher’s tomb, for they express the profound and essential meaning of his system.
I. THE SO-CALLED “PRE-CRITICAL WRITINGS.”
a) Writings from 1755–56. – In addition to the Latin dissertation *De igne* (1755) and the *Monadologia physica* (1756), notable works from this period include the *Allgemeine Naturgeschichte und Theorie des Himmels* (1755), published anonymously, which sets forth the hypothesis (later made famous when revived 41 years later by Laplace; hence it is known as the Kant-Laplace theory) that the solar system and those of other celestial bodies originated from a primordial nebula; and the Latin dissertation *Principiorum primorum cognitionis metaphysicae nova dilucidatio* (1755), which already contains the formulation of the argument for the existence of God, to be developed in a later work, and where there is a lively interest in the problem of knowledge, particularly “metaphysical knowledge.”
b) From the writings of 1762 to the *Dissertatio* of 1770. – If the works listed above are considered as belonging to the period of “dogmatic rationalism,” those that follow are seen as evidence of the so-called “scientific empiricism” period; specifically: *Die falsche Spitzfindigkeit der vier syllogistischen Figuren* (1762); *Der einzig mögliche Beweisgrund zu einer Demonstration des Daseins Gottes* and *Versuch, den Begriff der negativen Grössen in die Weltweisheit einzuführen*, both from 1763; *Untersuchung über die Deutlichkeit der Grundsätze der natürlichen Theologie und der Moral* (1764); and finally *Träume eines Geistersehers, erläutert durch Träume der Metaphysik* (1766). This group of writings presents
Kant already shows signs of the influence of English empiricism from Bacon and Hume. Kant begins to subject the principles of Leibnizian-Wolffian rationalism to critical revision, not in the sense that he doubts the validity of reason, but in the sense that he does not see its efficacy and validity beyond the limits of experience. In particular, it should be noted that in the essay on Negative Quantities, although he does not deny the objective validity of the principle of causality, he highlights how the cause-effect relationship remains incomprehensible, insofar as the “synthesis of reality” that it expresses is not reducible, as rationalism claimed, to the analytic procedure of pure logical thought. Kant now poses the problem without providing a solution. It should also be noted that the critical stance within dogmatic rationalism is directed not so much toward metaphysics as toward the knowledge of the sensible world; that is, rationalism finds a limit precisely in the explanation of the sensible, not in that of the supersensible. Evidence of this is also found in the fact that in the same year Kant resumes his extensive treatment of what he considers the only possible argument for a demonstration of the existence of God, in the eponymous essay. It can be formulated as follows: to think is to affirm the possibility of an object; now, nothing can be thought without the absolute necessity of a being being implicitly contained in thought itself, because it is necessary while existing; this being is being in general, common to all our concepts, which are determinations of it; therefore, being in general is the rational possibility, the foundation of particular possibilities. Such a being cannot be denied without denying thought, insofar as there is something thinkable for being in general; hence, possible being is absolutely necessary; but since every possibility has its foundation in a reality or existence, therefore God exists as the principle of absolute possibility, the source of all reality. However, already in the Untersuchung of 1764, Kant considers it more necessary to “persuade oneself” of the existence of God than to “demonstrate” II. In the historical essay Träume, confidence in reason’s capacity to know the supersensible and to demonstrate existence is shaken. Indeed, in examining the fantasies of Swedenborg—a Swede then famous in Europe for his spiritualist faculties and author of the eight volumes of Arcana Coelestia—Kant finds occasion to satirize the constructions of metaphysicians who claim to know everything about the supersensible. Instead, it eludes our cognitive faculties and cannot be either affirmed or denied. Already at this stage, for Kant, metaphysics has a negative value (it demonstrates that its objects exceed the possibilities of reason) and a positive one, not with respect to metaphysics itself, but to the concepts of experience. Kant’s dual position (which is ultimately one) begins to take shape: metaphysics as the “science of the limits of human reason,” and philosophy as the determination of the concepts of experience upon which our judgments rest. As can be seen, the two phases outlined here do not present great discontinuities: ultimately, as some scholars have argued, critical elements can be found in the writings of the so-called dogmatic rationalist period, and rationalistic elements in those of the so-called empiricist-scientific period. Kant recognizes the truth contained in both the rationalistic and empiricist stances and, amid oscillations and uncertainties, seeks the point of resolution. One cannot yet speak of a conscious awareness of the “criticalist” position (at most, it is implicit or barely glimpsed), nor of absolute dogmatism or outright skepticism.
The criticalist position, however, becomes manifest in the *Dissertation on the Form and Principles of the Sensible and Intelligible World* (1770), which is unanimously regarded as the beginning of the so-called “critical period.” Here, the fundamental initiative of the a priori is already present, even if the full development and extensive application that would come later are missing. In the *Dissertation*, we find what will become the transcendental aesthetic in the *Critique of Pure Reason*: space and time are a priori forms of intuition, and through them the sensible world is constituted as phenomenality. Thus, sensibility does not allow us to know reality as it is in itself (the supersensible), which instead is given to us by the intellect through innate concepts (virtual or Leibnizian-Wolffian innatism).
From this perspective, the *Dissertation*, while containing the discovery of the a priori and the phenomenality of sensible knowledge, represents, with regard to the problem of metaphysics, a less “critical” position (in the Kantian sense of the term) compared to earlier writings. This explains why Kant, before writing the first *Critique*, meditated for ten years on the discovery of 1770.
II. WORKS OF THE CRITICAL PERIOD
They begin with the *Critique of Pure Reason* (1781), Kant’s masterpiece, where the a priori is developed in its full critical scope and extends even to metaphysical knowledge. This was followed by the *Prolegomena to Any Future Metaphysics That Will Be Able to Come Forward as Science* (1783), which addresses the problems of the *Critique* in a new form, designed to facilitate understanding and dispel misinterpretations and obscurities. The *Groundwork of the Metaphysics of Morals* (1785) and the *Critique of Practical Reason* (1788), another fundamental work, apply the principles of criticalism (the name given to Kant’s philosophy) to the moral problem; the *Critique of Judgment* (1790), the last major work, addresses the problem of finality in nature. Among the minor writings, mention should be made of: *Metaphysical Foundations of Natural Science* (1786); *Religion Within the Boundaries of Mere Reason* (1793), the most notable of this group; *The Metaphysics of Morals*, which includes *Metaphysical Foundations of the Doctrine of Right* and *Metaphysical Foundations of the Doctrine of Virtue*, as well as the *Logic* (1800) and the *Pedagogy* (1803).III. THE PROBLEM OF THE “CRITIQUE.” — Criticism presents itself first and foremost as a question of method and in this sense continues historically the great dialogue between rationalism and empiricism, which, though divided, are united (from Descartes and Bacon onward) precisely by this problem, formulated as follows: to form true ideas about reality, should we start from reason or from experience? In the first case, our ideas correspond to real things (as rationalism maintained), so that the deductive process of thought translates that of reality; or else reality is given only by experience (as empiricism countered), but only insofar as it appears, leaving unresolved the question of whether ideas (“sensible impressions”) correspond to things as they are in themselves. Rationalist deductivism, whose typical method was the geometric method, had no doubts about the efficacy of analytic a priorism as establishing a necessary connection among all beings, the only objective and therefore true knowledge. Empiricism, in turn, pressed its critical claims, namely the impossibility of deducing concrete reality from abstract principles, so that experience proves to be a twofold limit of reason, both with respect to the sensible and the supersensible.
The insufficiency and one-sidedness of the two methods force K. to restate the problem of method in precise terms: a priori “analysis” of concepts cannot acquaint us with reality; knowledge is “synthesis” or “connection” of data that only experience can supply, yet synthesis is impossible (and cannot have objective validity) without rational elements. If the “intuition of concepts” nourished the rationalist illusion of a purely analytic, a priori knowledge, the synthetic character of knowledge itself gave rise to the empiricist illusion that mere sensory experience suffices to constitute knowledge. “Judging” (which for K. is “knowing”) is neither adding to a representation (subject) another (predicate) in a purely empirical connection, nor analytically decomposing the concept serving as subject and predicating one of its elements. The empiricist’s are “synthetic judgments,” but a posteriori (they contain only sensible elements or states of consciousness) and hence valid only subjectively; in them the connections are contingent, of “succession” and “coexistence” of data, lacking anything necessary or universal. The rationalist’s are “analytic judgments a priori,” yet precisely because they are “analytic” they are merely “explicative,” even if objective because deduced from rational principles independent of experience (Critique of Pure Reason, Introduction, § 4, Italian trans. by G. Gentile, Bari 1924, I, pp. 44-47). In short, the former are synthetic judgments, but only a posteriori; the latter are a priori, but only analytic. Thus the problem is posed: by deepening the concept of experience, may we not discover conditions independent of it or a priori that render experience itself possible? The question is no longer whether we have innate (a priori) knowledge, but whether in experience there are elements more a priori—conditions of experience that confer objectivity on human knowing. Hence “the objectivity of knowledge” is given by reason (the only faculty capable of giving it, in keeping with the rationalist’s legitimate demand), yet since it is sensibility that supplies the data, there is no knowledge without a posteriori content to which those a priori elements may be applied, constituting it as experience. Reason’s activity is therefore “synthetic” (or connective of sensory data) a priori, inasmuch as the elements of connection belong to reason itself and are immanent in II.
Are such judgments possible—i.e., syntheses of an a priori element or form and an a posteriori content? Are “synthetic judgments a priori” possible, and not merely “analytic a priori” (rationalism) or “synthetic a posteriori” (empiricism)? This is precisely one of the two central problems of the Critique of Pure Reason (Introduction, § 6, op. cit., I, pp. 51-52): to determine what the a priori elements or forms of our mind are and how they constitute experience. On the other hand, since a priori forms require sensible content, the question arises “whether a metaphysics as science is possible,” given that metaphysics’ objects are supersensible. This is the other fundamental problem of the Critique. Criticism thus presents itself as “critique of experience,” in that “synthetic judgments a priori” are possible through the forms of reason, and as “critique of metaphysics,” in that the concept of “synthesis” sets metaphysics as the limit of reason itself, since its objects are more, i.e., not mixed with anything derived from experience. Criticism’s demands are thus framed in the new concepts of experience and synthesis: “experience” is not adding a sensible to a sensible (empiricism), but the construction of the rational subject, for it is possible only through the necessary and universal relations established among sensibles (phenomena) by the a priori activity of thought; and “synthesis” does not mean adding a form to a content (as liquid poured into a vessel), but the subject’s constructive activity in organizing sensory data, which in themselves are not experiences, according to its own universal and necessary laws or forms. It is not nature that imposes laws on thought, but thought that gives laws to nature. This is what K. himself calls the “Copernican revolution” in philosophy: not the subject conforming to the object, but the subject as the orderer and builder of the world of experience, which is an irreducible synthesis of form and content, so that pure form without content is “empty” and mere content without form is “blind.” To prove that the human subject is capable of synthetic a priori knowledge is for K. to prove that mathematics and pure physics are possible as sciences (ibid., op. cit., I, pp. 49-51), yet not yet that metaphysics is possible as science, since its objects are supersensible. There is, however, a “natural metaphysics,” as a human, spontaneous, and profound exigency for the supersensible, which, whatever failures any metaphysical construction may encounter, is indestructible. Can this exigency be satisfied? And to what extent is a pure a priori knowledge possible? Before reason “dogmatically” abandons itself to metaphysical flights beyond the limit of experience, like the dove that “might imagine it could fly far better in airless space” (ibid., Introduction, op. cit., I, p. 43), it must “critically” examine its own capacities before the “tribunal” of itself, to decide, according to its eternal and immutable laws (ibid., Preface to 1st ed., op. cit., I, p. 7), whether it is permitted to found metaphysics as science or is condemned to experience, every a priori construction being a mere “illusion” (ibid., Preface to 2nd ed., op. cit., I, p. 31). The critique of reason is therefore the critique of pure reason as activity independent of experience. Yet it is evident that the problem of metaphysics, thus posed, refers back to the solution of the other problem hinted at above: what are the conditions of the objective validity of knowledge in general? In this sense the first two parts of the first Critique are an introduction to the solution of the problem of metaphysics, which remains the central problem of criticism. Hence for K. the task is no longer to construct a theory of knowledge, but to establish the critique of knowing in general, to ascertain how far man is capable of objective knowledge and whether reason possesses the means to construct metaphysics as a rational science. Hence the parts of the Critique of Pure Reason: “Transcendental Aesthetic” (“aesthetic” in the sense of a doctrine of “sensibility” in general) or philosophy of mathematics; “Transcendental Logic” or philosophy of pure physics, divided into “Transcendental Analytic” (analysis of a priori concepts) and “Transcendental Dialectic” (or critique of the dialectical illusion of reason, or of reason’s use of a priori concepts beyond experience).
IV. THE «A PRIORI» FORMS OF KNOWING AND THE MYTHS OF PURE REASON
Knowledge that refers to objects and which every thought aims at as a means is what K. calls intuition (v.). The capacity (receptivity) to receive representations in the way we are modified by objects he calls sensibility. Therefore, objects are given to us by means of sensibility, and it « alone provides us with intuitions»; but these are thought by the intellect, from which concepts derive. The action of an object upon the representative capacity, in so far as we are affected by it, is sensation. That intuition which refers to an object by means of sensation is called empirical intuition. The indeterminate object of an empirical intuition is called a phenomenon, of which « the matter is what corresponds to sensation », while « form » is that « by which the manifold of the phenomenon can be ordered in determinate relations ». All representations in which nothing belonging to sensation is mixed are « pure », and thus the pure form of sensible intuitions is found in the mind; this is what K. calls pure intuition. Transcendental aesthetics is the « science of all the a priori principles of sensibility » (Crit. d. r. pura, I, part 1, § 1, cited ed., pp. 63-65). « Transcendental » is the term by which K. indicates the a priori, that is: it is not « empirical », inasmuch as it is not derived from or dependent upon experience; nor is it « transcendent », inasmuch as, although not derived from experience, it is valid only when applied to it, as a law or form by which we know the objects of experience itself.There are two forms of sensible intuition: space or outer sense, by which we represent objects as outside us; it is not an empirical concept, but a « necessary a priori representation » which underlies all outer intuitions, and renders geometry possible « as a priori synthetic knowledge » (ibid., I, part 1, § 3, and sect. 1, § 3, pp. 67-69); and time or inner sense, likewise non-empirical and a necessary a priori representation, in which « two contradictory opposite determinations can meet together in one thing, one after the other » (ibid., sect. 2, § 5, p. 75). Apart from these two transcendental forms (or a priori conditions) of sensibility, no experience is conceivable.
To intuit an object sensibly is not to think it, and thus other relations are required to transform intuitions into concepts. It is the intellect, by means of its own « functions » or categories, that unifies the manifold intuitions and formulates synthetic a priori judgments. K. distinguishes (in the second part of the Critique of Pure Reason, called « Transcendental Logic », and precisely in that section termed « Transcendental Analytic ») judgments according to: 1) quantity; 2) quality; 3) relation; 4) modality; and from these classes of judgments he derives twelve categories respectively: 1) unity, plurality, totality; 2) reality, negation, limitation; 3) substance and accident, cause and effect, action and reaction; 4) possibility and impossibility, existence and non-existence, necessity and contingency. By means of these universal and necessary categories, the intellect constitutes sensible impressions as thought objects. Yet in order that manifold representations may be unified, they must be brought back to a point of reference. This centre, for K., is the consciousness I have of being always the same. Thus, through the identity of my consciousness, in the succession of representations, I can establish relations among them and thus unify them into an object. The « I think » (Ich denke) is the condition of their unity. But it is not enough that the representations are in me: in the act of unifying them, they are mine, yet distinct from me, my representations but of something. Individual subjects presuppose a deeper unity, which K. calls consciousness in general (Bewusstsein überhaupt) or transcendental ego, or the organizing activity, according to universal laws, of all possible representations of all possible empirical consciousnesses. Consciousness in general in every subject is expressed as the transcendental unity of self-consciousness, which manifests itself in the « I think ». This consciousness does not act outside individual consciousnesses, inasmuch as the « I think » cannot be abstracted from inner sense, proper to empirical consciousness, which becomes self-consciousness because through it the universal consciousness acts (ibid., I, part 2, §§ 17-18, pp. 133-35). The « I think » is the legislator of nature, the builder of the world of experience, the unifier of the manifold into concepts of objects. Yet it is not known as such, as « res cogitans » or substantial soul, but as transcendental activity, that is, in its modes of « functioning ».
There is, however, a heterogeneity between pure concepts or categories—forms of possible concepts—and sensory impressions. And so, « how is the subsumption of these under those possible, and thus the application of the category to phenomena? » (ibid., I, part 1, book II, chap. 1, p. 159). K. resolves the problem with the doctrine of schematism: there is a third term, homogeneous on the one hand with the categories and on the other with the phenomenon, which renders possible the application of the former to the latter; this is the transcendental schema. The schema is in itself a product of the imagination, yet it must be distinguished from the image. « Now I call the schema of the imagination of a concept the representation of a general procedure whereby the imagination procures for a concept its image. In fact, underlying our pure sensible concepts there are not images of objects, but schemata » (ibid., p. 161). The schematism of our intellect is « a hidden art in the depths of the human soul ». « We can say only this: the image is a product of the empirical faculty of productive imagination; the schema of sensible concepts (such as figures in space) is a product, so to speak, a monogram of pure a priori imagination, by means of which and according to which images first become possible; yet these images, moreover, can be related to the concept only through the schema, which they designate; and in themselves they never coincide perfectly with it (the concept) » (ibid., p. 162). The schema of substance, for example, « is the permanence of the real in time, that is, the representation of the real as the substratum of the empirical determination of time in general; a substratum which therefore remains, while all else changes »; and the schema of cause is the real, to which, once it is posited, something else always follows. It thus consists in the succession of the manifold, in so far as it is subject to a rule » (ibid., p. 163), and so on. « The schemata therefore are nothing but a priori determinations of time according to rules, and these rules, in the order of the categories, refer to the series of time, its content, its order, and finally to the totality of time in relation to all possible objects » (ibid., p. 164). From what has been said, two conclusions may be drawn
sioni: a) the objectivity of knowledge (mathematics and physics) is given by the a priori links that the subject establishes among sensory data; b) the transcendental a priori forms are valid only when applied, as unifying principles, to sensory data. Consequently, our knowledge is only of phenomena. But K. does not identify all reality with the phenomenon. We receive sensory impressions, and thus there is a reality in itself from which the impressions derive; however, we always learn reality as it appears to our consciousness, that is, through the subjective forms of space and time. Yet man naturally aspires to knowledge of the unconditioned or the absolute, the object of metaphysics. Is it possible to satisfy this aspiration? As we know, for K., if one of the two elements of synthesis is lacking, there is no longer knowledge; now the unconditioned is not given by any experience, and therefore to claim to know it with the forms of the intellect is to make these latter function in a void, since a content is lacking. Criticism therefore acknowledges the irrepressibility of the metaphysical demand, but declares unjustified and impossible to realize the pretension of reason to know the supersensible. To these pretensions of knowledge K. gives the name of Ideas (pure form devoid of sensible content); and he reduces to three the Ideas of pure reason corresponding to the three fundamental problems of special metaphysics, according to the systematization of Wolff, namely: a) the idea of the absolute unity of the pure subject, or the idea of the soul as substance (rational psychology); b) the idea of the absolute unity of the series of phenomena (rational cosmology); c) the idea of the absolute unity of all objects of thought (rational theology). In short, the ideas of the soul, the world, and God. In attempting to solve these problems, reason becomes entangled in false inferences (paralogisms and sophisms) and in contradictions, inasmuch as it extends the a priori forms of the intellect beyond experience. It fashions and deludes itself into believing it knows objects corresponding to them (K. devotes more than half of the Critique of Pure Reason to the treatment of the Ideas of reason, and precisely the other part of the Logic, which he calls the "Transcendental Dialectic").
Indeed: a) rational psychology makes of the soul a simple, immortal substance, etc. The paralogism lies precisely in making of the "I think," which is known as the synthesizer of experience, a substance, that is, in claiming to know the soul beyond experience and illegitimately using the category of substance, which is valid for unifying phenomena. "I think myself as subject of a possible experience, while I am still far from any actual experience, and I conclude that I can have consciousness of my existence even outside of experience and the empirical conditions of II. Thus I mistake the possible abstraction of my empirically determined existence for the pretended consciousness of a possible existence separate from my thinking self, and I believe I know what is substantial in me as a transcendent subject, whereas in thought I have simply the unity of consciousness, which is the foundation of every determination as the mere form of knowledge" (ibid., II, p. 327). b) Similarly, rational cosmology claims to attain an unconditioned principle representing the totality of phenomena and their conditions. From this pretension arise what K. calls the antinomies or conflicts of pure reason, in each of which the thesis and antithesis are equally justifiable. But both thesis and antithesis proceed from a mistaken presupposition, namely, they presuppose that it is possible to know the idea of the totality of phenomena (the unconditioned), when such an idea is never given by intuition. c) Lastly, rational theology claims to demonstrate the existence of the Supreme Being or God. For K., three proofs are possible: the ontological, the cosmological, and the physico-theological. We limit ourselves to mentioning the critique of the ontological proof, which considers the proposition "God exists" to be analytic, that is, the predicate of existence is contained in the essence of the subject. K. observes: "you have already committed a contradiction when, in a concept of a thing that you wished to think solely in its possibility, you have introduced, even under a hidden name, the concept of its existence" (ibid., II, p. 371). In logical use, "being" is not a real predicate but the copula of a judgment. Therefore, when I say "God is," I do not affirm a new predicate of the concept of God, and thus "the real does not thereby contain anything more than the merely possible. A hundred real thalers do not amount to anything more than a hundred possible thalers... The object of reality is not analytically contained in my concept, but is added synthetically to my concept (which is a determination of my state) without this thereby adding anything intrinsic to my concept; these same hundred thalers of thought are not in the least increased" (ibid., II, pp. 472-73). In the case of the most perfect Being or God, existence cannot be added synthetically because there is no sensible content of God, it is beyond experience. Pure reason can therefore not demonstrate the existence of God: experience is the limit of human knowledge. K. concludes that the pretension of pure reason to know the objects of metaphysics (the soul, the world, freedom, God) is unjustified and that, therefore, a metaphysics as science is not possible, precisely because there is science only of what is the object of experience. The use of the Ideas of pure reason is not epistemological, since the Ideas are not constituted principles of our knowledge, but only regulative or normative. He distinguishes between "natural theology" and "transcendental theology," the latter having an important negative use, and being a constant censure of our reason, if it is to deal simply with pure ideas, which for that very reason admit no other measure than the transcendental" (ibid., II, p. 499). If transcendental theology convinces reason of the impossibility of demonstrating the existence of God, on the other hand it convinces of the impossibility of denying II. "The Supreme Being thus remains, for the merely speculative use of reason, a mere but perfect ideal, a concept that crowns and completes all human knowledge, and whose objective reality, it is true, is not demonstrated, but cannot be contradicted either; and if there is to be a moral theology capable of supplying this defect, then transcendental theology, hitherto merely problematic, demonstrates its necessity for the determination of its concept and for the incessant censure of a reason often deceived by the senses and not always in agreement with its own ideas" (ibid., II, p. 500).
THE PRACTICAL REASON AND ITS POSTULATES
Only an a priori form or law can confer upon the will the character of universality and necessity. Consequently, morality cannot be founded upon subjective principles, such as sentiment in all its forms: sentimentalist, sympathetic, hedonistic, eudemonistic, utilitarian, etc., moralities are therefore insufficient (C. d. r. pratica, part 1, Italian trans., 3rd ed., Bari 1924, pp. 26 ff.). For an action to be moral, it is necessary that the will be independent of every particular object and that it determine itself unconditionally according to the law, which, for Kant, is duty (Grundlegung, ch. 1 § 4). "You ought" is the categorical imperative (imperativo categorico) because it is a command that demands obedience; "categorical" because it is unconditional, the tone which the law of practical reason assumes in us, valid for the will of every rational being (ibid., ch. 2, § 3-4). Man, however, is not merely pure will, but also has "inclinations" that impel him to act not from duty but from sympathy, pleasure, utility, etc. Morality is a strict discipline, a subordination of inclination to the law. The first formula of the categorical imperative thus reads: "Act only according to that maxim whereby you can, at the same time, will that it should become a universal law" (ibid., § 6). For this to occur, it is necessary that no particular content determine my action. If, for example, I act for my own advantage, the maxim of my action holds good for me—and for me in those particular circumstances—and cannot hold good for all (another in my place might act differently). In this case, the maxim of my action is empirical and subjective and therefore not a universal law of conduct. The categorical imperative therefore commands no particular action, no
determinate good, since there is no good or action, however noble, that can be universally and always valid for all rational beings. Every particular good is always conditioned by particular circumstances: for example, you ought even to die, if the fatherland is in danger. This command holds not universally, but in a particular circumstance (it is a hypothetical imperative). In every action, therefore, one must always distinguish the law or form from the content. The content or matter of the will is particular and a posteriori; the form is the universal law a priori. Now a particular action is moral when it is willed according to the form or rational law, not for the effects we expect from it, but for the duty of doing II. Only thus can a particular end enter into a universal order. In short, only the action conforming to the law is good, and only the will that determines itself according to the law is good. Only the rational being is a moral person and therefore an end in itself. Hence the second formula of the categorical imperative: "Act in such a way that you treat humanity [rationality], whether in your own person or in the person of any other, never merely as a means to an end, but always at the same time as an end" (ibid., II, § 10). Now the subject of all ends is every rational being as an end in itself (on the basis of the second principle); from this there follows the third practical principle of the will as the supreme condition of its harmony with universal practical reason, namely, the idea of the will of every rational being considered as a will that legislates universally" (ibid., § 12).
The will that determines itself according to the law is autonomous, unconditional; if it determines itself for any other reason, it is heteronomous (Cr. d. r. prat., part 1, ch. 2, § 8, pp. 40-41). Therefore, according to Kant, placing the motive of action in the sentiment of pleasure or pain, of utility or interest, in instinct or anything else, is to deny the autonomy of the will. Even if the command is placed in God, such autonomy ceases. All techniques other than his are therefore heteronomous. The fact that the will ought not to depend on external circumstances and that the law commands nothing in particular has led to the accusation that Kant is a "formalist," and not altogether unjustly. It must however be recognized that for Kant the content is indispensable to moral action. He does not say to act without inclination, but to act from duty. One can therefore act also with inclination, provided that the end of the action is always the fulfillment of the law. Morality thus conceived is distinguished from legality, which is external conformity to the law (ibid., part 1, ch. 3, p. 26). The law is satisfied with legality, with external sanction. An action can therefore be not juridically condemnable, yet morally condemnable. If I do not steal merely from fear of prison, I cannot be punished, but morality still condemns my intention to steal. The juridical order, which with external coercion imposes respect for the law, is necessary to society, inasmuch as it makes possible the coexistence of individual freedoms, i.e., it prevents the abuses of one from obstructing the freedom of others. For the law to exercise this function, however, a power is necessary to enforce it, namely, the authority of the State. For Kant, the function of the State is limited solely to the protection of right.
With morality we enter the world of the supersensible, of the unconditional, and it is therefore permissible to re-examine the problems of metaphysics in the sphere of practical reason. Morality and the autonomy of the will are not possible without freedom, which is therefore a postulate of morality. Moreover, virtue, unconditional moral good, is not the supreme good, even if it is the "highest good"; to it must be added happiness (Cr. d. r. prat., part 1, p. 11, § 13, pp. 133 ff.). The perfect adaptation of the will to the moral law is holiness. No rational being in the sensible world, at no point in his existence, is capable of this perfection. From the need to realize perfection and to attain the supreme good, and from the impossibility of realizing it in this life, arises the faith in the immortality of the soul (the second postulate of morality), which makes us believe that we continue, beyond this life (ibid., ch. 2, § 4, p. 146 ff.), the progress toward perfection. For the realization of complete good, i.e., for the attainment of virtue accompanied by happiness, a third postulate is necessary: the existence of God. For since nothing in nature guarantees the union of virtue and happiness, it is necessary to postulate the existence of a cause of the world distinct from the world itself, as the principle of the connection of happiness and virtue. This cause is God (ibid., ch. 2, § 5, p. 148 ff.). Freedom, the immortality of the soul, and God are the three postulates of morality.
Thus the three regulative ideas of speculative reason are now necessary truths for practical reason. Not that there is objective knowledge of the metaphysical ideas, but only a practical necessity to admit their existence. Speculative reason recognizes the legitimacy of the demands of practice, but moral faith is not a demonstrated truth; and therefore an extension of pure reason in the practical respect is conceivable, without thereby extending its knowledge as speculative (ibid., part 1, p. 11, ch. 2, § 6, pp. 160 ff.). In other words, for practical exigencies, man acts as if the will were free, the soul immortal, and God existent. Thus practical persuasion (I am "subjectively" persuaded that God exists) and not rational demonstration valid "objectively." "Transcendental theology" authorizes only "moral theology" and not "natural" or "rational" theology.
The theoretical and practical principles already set forth contain a pedagogical conception, namely the autonomous formation of the personality. K.’s pedagogy (a collection of lecture notes compiled by a disciple) is a speculative deepening of Rousseau’s *Émile* (v.). K. opposes all forms of sentimentalism: the autonomy of the person is realized in the strict and conscious subordination to the law of duty, which coincides with freedom. Only respect for the law is capable of forming a character, of making man feel his own dignity, and of revealing to the spirit an unsuspected strength to detach itself from every sensible affection and to find in the independence of its intelligible nature and in the greatness of soul a recompense for its sacrifices. For K., man by nature is neither good nor bad. He becomes good when he rises to the idea of duty and law. The aim of education must therefore be precisely to render man morally good, that is, to give him possession of virtue, which is mastery of self, autonomy, and freedom of the person.
K. also treats the problem of religion from the standpoint of criticism; religion within the limits of mere reason is a rationalist interpretation of Christian doctrine (the supersensible can be represented only symbolically: “symbols” of moral virtues, having only practical value, are the dogmas of positive religions), so much so that, because of his Enlightenment spirit, Frederick William II of Prussia admonished the aged philosopher to refrain from undermining the foundations of Christianity.
VI. THE END OF NATURE
The world of phenomenal nature is governed by necessity, the moral world by freedom; hence the two worlds are antithetical. Man participates in both, and therefore it is not indifferent for him to know whether nature obstructs or does not obstruct the realization of his ends. That is: is a teleological representation of the world possible, in which the mechanism of natural causes does not present itself as an obstacle to the attainment of the ends of moral life? It is precisely this problem that K. proposes to solve in the *Critique of Judgment*. To this end he introduces a new form of judgment, the reflective judgment (distinct from the determinant judgment, in which the universal—the category—is determined in the particular to which it is applied), in which, given the intuition of the particular, the mind reflects upon it in order to connect it with a universal that is not a concept but is lived in feeling (Introduction, IV, Italian trans., Bari 1923, p. 17). The *Critique of Judgment* has as its object the reflective judgments, by which the particulars of nature are referred to a universal order of finality in which they are comprehended.Two forms of reflective judgment render a teleological representation of nature possible: the aesthetic judgment and the teleological judgment. The aesthetic representation is the intuition of the pure form of the Beautiful: given only the particular, the judgment finds the universal in it, that is, it refers it to the pure form of the Beautiful. “The pleasure of the beautiful is neither a pleasure nor enjoyment, nor of an activity conforming to laws, nor of contemplation reasoning according to ideas, but a pleasure of mere reflection; and, without being guided by any purpose or principle, accompanying the common apprehension of an object, which results from the imagination, as a faculty of concepts, by means of a procedure of judgment that must also be found in the most common experience; with the difference, however, that in the latter case the judgment aims at an empirical objective concept, whereas in the former (in the aesthetic judgment) it has only the purpose of perceiving the finality of the representation with respect to the harmonious action (subjectively final) of the two cognitive faculties in their freedom, that is, of feeling with pleasure the state of the representative activity” (ibid., part 1, sect. 1, I, II, § 39, p. 145). This is a disinterested enjoyment that suggests an accord between nature and our faculty of knowing, as if nature were constituted to arouse in us this enjoyment. The aesthetic feeling (as feeling and pleasure) is not subjective subjectivity but objective, inasmuch as for K. the Beautiful is a universal form like the True and the Good. This correspondence between ourselves and things is even more evident in living organisms, where the accord among the various parts of a being is thought by us as determined by the concept of end (teleological judgment). But reflective judgments always have a “regulative” and not a cognitive value. Not a “physical theology,” but a “physical theology” (properly physico-theological), which “can at least serve as a propaedeutic to a true theology, by providing, through the consideration of the ends of nature of which it offers a rich material, the idea of a final end that nature cannot establish; and thus it can make felt the need for a theology that sufficiently determines the concept of God for the supreme practical use of reason, although it cannot produce and found it in a sufficient manner on its proofs” (ibid., part 2, sect. 2, p. 368).
VII. The key to the entire Kantian system—architectonic, complete, and powerful in its depth and originality of inquiry (it is a mandatory passage point in philosophical research and has influenced world thought)—is the discovery of the a priori as transcendent, that is, as the objective form of sensible content. From this follows: a) that knowledge is of the phenomenal; b) experience is the limit of knowledge; c) hence a metaphysics as science is not possible, but only as moral faith. Yet the reduction of the a priori or of the categories to pure transcendental conditions is an unjustified assertion, not critically deduced or demonstrated. K. reduced the real elements of knowing to functions of the intellect, and it is evident that the objectivity of knowledge no longer escapes a fundamental subjectivity; indeed, the knowledge of things is known through phenomena, and the world is our “representation.” If ideas are empty forms of sensible context, their functioning remains blocked by experience, and valid knowledge only within these limits, that is, within the limits of physical-mathematical science. In this way, the critical concept of the a priori, whose functional limit lies in experience, and the critical concept of experience, whose limit lies in the a priori that organizes it, are only half-critical: they are critical of the concept of science but not of the concept of metaphysics; the a priori finds its adequation in the world (in the natural order: “the starry heavens” and “the moral law”), and consequently the world is its supreme end, and thus also its initial beginning. In short: with this, God is eliminated from the order of thought and from the order of reality; it is no longer possible to explain how the exigency of God and the Ideas of reason can arise, which within the Kantian system are not even justified as postulates of practical reason: K. introduces them, but they remain extraneous to the Critique as he understands it, which resolves itself into the system of “cosmicity” (M. F. Sciacca, *Filosofia e metafisica*, Brescia 1950, pp. 188-189). Critical reason is not that which denies to itself the capacity to surpass experience, but is reason that knows it cannot but surpass experience and itself. Only if reason knows that truth is more, not less, than itself does it rediscover itself with God. Hence the problem of the existence of God is not added to experience (as if from the outside), but is implicit in the very problem of experience and in experience itself. In this sense, experience is witnessing: by the fact that I exist (and the world exists), God exists. If God were only an Idea of reason in the Kantian sense, He would be a mere possible; but to say that God is only possible is to say that He is impossible; and everything suddenly becomes impossible and inexplicable. The true critical problem is not that of the limiting of reason’s experience, but of the critique of experience, that is, to prove that the problem of experience, adequately resolved, rationally demonstrates (not merely as a moral exigency) the existence of God. The fact is that the Kantian system tends to do without God, who is replaced by the “I think,” legislator of nature and of the moral world. The autonomy of pure and practical reason is significant in this regard: it signifies the foundation of natural and human science (morals, law, etc.) independently of metaphysics and hence of natural theology. K.’s thought is fundamentally atheistic and skeptical, and for this reason it has nourished all subsequent forms of lay (and dogmatic) rationalism, such as pragmatism and fideism. Kantian transcendentalism is therefore irreconcilable with the natural order of reason and with Catholic doctrine.
Italian translations: *Crit. della r. pura*, trans. by G. Gentile and G. Lombardo Radice, Bari 1909; *Crit. della r. pratica*, trans. by F. Capra, 1910; *Critica del giudizio*, trans. by A. Gargiulo, 4th ed., 1910; *Critici minori*, trans. by P. Carabellese, 1912; *Prolegomeni*, trans. by P. Martinetti, Turin 1913; *Fondazione met. dei costumi*, trans. by G. Vidari, Bari 1908; *Met. dei costumi*, trans. by G. Vidari, 1912; *Rel. nei limiti della rag.*, trans. by A. Poggi, Modena 1941; *Pedagogia*, trans. by N. Abbagnano, Turin 1930.
Bibliographic guide: E. Adickes, *German Kantian Bibliography*, New York 1895-96; Überweg, III, 12th ed., Berlin 1924, pp. 709-749.
Principal monographs: C. Cantoni, *K.*, 3 vols., Milan 1883; F. Paulsen, *K., sein Leben und seine Lehre*, Stuttgart 1898; T. Ruyssen, *K.*, Paris 1909; A. D. Lindsay, *The Philos. of K.*, London 1913; J. Ward, *A study of K.*, Cambridge 1922; P. Lamanna, *K.*, 3 vols., Milan 1925; E. Boutroux, *La philos. de K.*, Paris 1926; P. Carabellese, *La philos. di K.*, I, Florence 1926; A. Renda, *Il criticismo, fondamentali etico-religiosi*, Palermo 1927; still valuable: K. Fischer, *I. K. und seine Lehre*, Heidelberg 1860; E. Caird, *The critical philos. of K.*, London 1889.
On the precritical period: A. Guzzo, *K. pre-critico*, Turin 1924; E. Oggioni, *K. empirista*, Milan 1947.
On the *Critique of Pure Reason*: H. Vaihinger, *Kommentar zur K. d. r. V.*, 2 vols., Stuttgart 1881-92; F. Tocco, *Studi kantiani*, Palermo 1910; H. Cornelius, *Kommentar zur K. d. r. V.*, Erlangen 1926; L. Scaravelli, *Saggio sulla categoria kantiana della realtà*, Florence 1947. On moral philosophy: V. GELBOE, *La philosophie pratique de K.*, Paris 1905. On the doctrine of law and history: K. Borries, *K. als Politiker*, Leipzig 1928.
And this was seen in the test of facts: the definitive repression of brigandage in southern Lazio (1864-66) was followed by the valiant resistance opposed to Garibaldi’s bands in the autumn of 1867, as well as by the victorious action at Mentana (3 Nov.). Then came the final crisis of 1870: for K. and his men, as Vigevano rightly called it, it represented a veritable “drama of military psychology,” between a spontaneous spirit of combativeness even to the point of supreme sacrifice and disciplined obedience to sovereign orders aimed at reducing the clash to the minimum necessary to demonstrate the use of force. Even on that extreme occasion the papal militias led by K. knew how to command respect from honest combatants by fighting and obeying like a “good army,” so much so that they received the honours of war from the besiegers. Once the painful and arduous capitulation negotiations were concluded, and after bidding farewell to the troops departing into captivity, K. refused to leave the side of Pius IX, whom he had the fortune to attend until his final agony. Created a baron by Leo XIII, he spent the rest of his life aiding and benefiting his former soldiers, and devoting himself with success to studies of a military and astronomical nature.
Among other things, he is responsible for an objective *Rapporto alla S. di N. S. papa Pio IX sulla invasione dello Stato pontificio nell'autunno 1867* (Rome 1868), as well as an important collection of personal and governmental documents entrusted to the Vatican Archives by Msgr. A. Mercati in 1932.