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Kant, Immanuel


Immanuel Kant and Theology (Richard Peters, 2004)

Immanuel Kant (1724-1804) (Xiang He and Matt McLaughlin, 1998)

Immanuel Kant (1724-1804) (Wonbin Park, 2000)

Notes on Immanuel Kant (1724-1804) (Andrew Irvine, 1998)

Notes on Parts of Kant's Critique of Pure Reason (Roy Smith, 2008)

Immanuel Kant and Theology

Richard Peters, 2004

Biography and Historical Background

Immanuel Kant was born in 1724 in the Prussian city of Konigsburg (now Kaliningrad, Russia). Though his parents were too poor to ensure that Kant received an education, he was nevertheless sent off to school by his pastor at the age of 8 (Scruton, 1982, 1). His parents were Lutheran pietists and the school Kant attended was a pietist school, so Kant was strongly influenced by this movement from a young age (Scruton, 1).

“Pietism” names the dominant form of Christianity in Germany during the late seventeenth and early eighteenth centuries. The origins of pietism are attributed to the writings of the German Lutheran theologian Jakob Spener, whose movement reached into America and the present day (Welch, 1972, 23). It was originally motivated by dislike for religious detachment and creedalism, immorality, and Enlightenment philosophy, preferring religious affections and good works, holiness, and simple faith (Welch, 23). Welch (1972, 26-27) describes pietism as less a system of thought than of feeling

…in which all attention was centered on the heartfelt character of true religion, on inner conviction and peace, on the intensity of feeling, on the affective and the emotional elements in experience…. Whether in validation of accepted doctrine, or in defense against unbelief, the central thrust of the pietist movements was toward the interiorization of the Christian truth.

It was also marked by individualism and a corresponding emphasis on existential aspects of Christianity, such as the struggle against fleshly desire. In this last respect it had much in common with what are often identified as “Enlightenment” tendencies to devalue appeals to external authority and to identify religion with morality (Welch, 34-37).

The Enlightenment period in which Kant developed and labored was one of considerable intellectual excitement and uncertainty. Scientific advances in all fields stimulated hope in progress and gave new direction to thought and labor (Brooke, 1991, 154). Newton had unified—perhaps all but completed—physics with a few simple equations in the late seventeenth century, inspiring others to similarly broad aspirations. Confidence in human powers and possibilities was on the rise. Critics of religion proclaimed the value of free thought for human advancement (Brooke, 167-189). And yet the emphasis on progress also meant that traditional religious perspectives were undermined and devalued. Hume published his attack on metaphysics just prior to Kant’s major work, leaving philosophy drifting with no way to settle its disputes. Natural theologians of different stripes wrangled with each other over the meaning of various data (Brooke, 191-225). The plurality of opinions among all kinds of thinkers in this rapidly changing time encouraged a skeptical outlook.

Kant emerged from the contexts provided by pietism and the Enlightenment evidently deeply marked by their influence. It seems that he was inspired by the uncertainty of his times to provide sure, philosophical foundations for thought and action. He struggled to protect and promote the best of the new ideas (e.g., Newtonian mechanics) and to contest the worst (e.g., dogmatic metaphysics). He had apparently inherited a strong tendency to view religion in moralistic terms from his pietist background, and acquired a preference for individualism and a suspicion of ecclesiastical authorities as a gift of the Enlightenment.

In what follows I examine two of Kant’s writings in some detail, uncovering evidence of these historical influences along the way. I hope to prepare the reader for Kant’s views on religion as found in Religion Within the Boundaries of Mere Reason with an explication of his Prolegomena to Any Future Metaphysics. Kant also left a deep impression on subsequent thinkers, so this essay will end with a discussion of theology after Kant.


Prolegomena to Any Future Metaphysics

In the Prolegomena to any Future Metaphysics, Kant presents a “sequel” to his longer and more difficult Critique of Pure Reason (Prolegomena, 263). (Page numbers given for the Prolegomena refer to the marginal page numbers in the Hackett edition of James W. Ellington’s revision of the Carus translation.) His object in writing, as he states it on the first page of the Prolegomena,

…is to persuade all those who think metaphysics worth studying that it is absolutely necessary to pause a moment and, disregarding all that has been done, to propose first the preliminary question, ‘Whether such a thing as metaphysics be at all possible?’ (255)

But this is an unduly modest account of Kant’s aims. What he really hoped to do, it seems, was present accessible arguments for his conclusions: 1) that reason has a limited competence, 2) that it is necessary to identify those limits to discover the proper scope of reason, and, best of all, 3) that he, Immanuel Kant, had in fact identified those limits and thereby overcome skepticism, established the scope and possibility of any future metaphysic and ensured its rapid completion. Kant wrote for teachers of would-be metaphysicians (255), whom he evidently hoped would be better equipped to promote his thought upon receiving this “sketch” of it (263).

Toward answering the “just complaint” concerning a “certain obscurity” in the presentation of the Critique of Pure Reason (261), Kant approaches his subject in the Prolegomena according to an “analytical” (in contrast to a synthetic) method (263). That is, he begins not by aspiring to identify the preconditions of pure reason from scratch (as in the first Critique), but by picking out paradigmatic examples of pure knowledge and then dissecting them to reveal their parts. This procedure simplifies the discussion so considerably in Kant’s estimate, that, besides measuring the competence of pure reason itself, the Prolegomena also measures the competence of any who aspire to reasoning. In Kant’s words:

…should any reader find this plan, which I publish as the Prolegomena to Any Future Metaphysics, still obscure, let him consider that not everyone is bound to study metaphysics…. (263)

Thus encouraged, I will now attempt to explicate the Prolegomena.


History seems to confirm Kant’s observation that the metaphysicians of his day were restless, unable to attain any consensus concerning metaphysical matters but equally unable to settle their minds by leaving off the pursuit. According to Kant, this state of confusion gave opportunity to incompetents who supposed that they could settle metaphysical questions with assertions or appeals to common sense and tradition (256, 259). The result of this uncertainty and “shallow talk” was a growing skepticism, which Kant seems to have regarded as both a sign and cause of social unrest. Kant sought to extinguish this skepticism—and thereby ensure social stability—by attaining metaphysical certainty.

But in addition to the incompetents doing metaphysics was David Hume, who had interrupted Kant’s “dogmatic slumber” with his careful analysis of the origin of our ideas of cause and effect (260). Hume had “demonstrated irrefutably” that we are unable to get behind appearances to a priori knowledge of causes and effects (257). Presupposing with Locke that all the mind’s contents are obtained through the senses, Hume went on to argue that belief in causation was a mere “custom” arising from the “constant conjunction” of events, and thereby reduced causation to an empirical idea. Hume used this argument to show that metaphysics is impossible, thereby undermining the natural theology that depended on it and contributing to the growing skepticism of the age. Kant recognized that Humean skepticism extended—not just to cause and effect—to all metaphysical concepts. The threat of skepticism loomed large.

Though other philosophers were satisfied to offer dogmatic and “sensible” responses to Hume’s analysis of human understanding, Kant responded by attempting to penetrate reason through reasoning even more deeply than Hume (259). The results of that work are described in the rest of the Prolegomena.

1. Preamble on the Peculiarities of All Metaphysical Cognition

In chapter one of the Prolegomena, Kant describes what he thinks is the essential characteristic of metaphysics, and then identifies two further sciences that share that feature (mathematics and Newtonian physics) toward establishing grounds for further comparison. The possibility of metaphysics is in question, but mathematics and physics are unquestioned actualities for Kant. Because all three sciences have the same essential characteristics, Kant believes that he can reveal the possibility of metaphysics by exposing the conditions for the actuality of math and physics. In other words, comparing the three sciences provides justification for the analytic method that Kant uses in the Prolegomena to expose the structure of reason and thereby establish metaphysics.

The essential characteristic of metaphysics, according to Kant, is that it is entirely concerned with synthetic a priori propositions (274). A priori cognitions are not obtained through the operation of the senses as are a posteriori cognitions; a priori cognition is non-empirical in origin. According to Kant, empirical cognitions can play no role in metaphysics because metaphysics is by definition about that which lies beyond or behind experience (265). In addition to a priori (and a posteriori) cognitions—which provide the raw data of thought—Kant considers two kinds of judgment that operate on them: analytic and synthetic judgments. Analytic judgments render explicit—through the principle of non-contradiction—what was implicit in a particular concept. (Kant offers “all bodies are extended” as an example of an analytic judgment, the idea of extension being implicit, as he sees it, in the concept of a body, such that “body” cannot be coherently thought without the accompanying idea of extension.) All analytic judgments are a priori and merely make explicit what one knew already (266-267). Synthetic judgments on the other hand, are “ampliative,” that is, they yield more information than can be derived from the individual pieces that are involved in the judgment. Most synthetic judgments are empirical in nature, but some, Kant argues, are a priori.

As noted above, Kant recommends mathematics and theoretical physics as bodies of knowledge that consist entirely of synthetic a priori judgments. We will examine some of his arguments for this conclusion in the next section of this paper. For now it is enough to note that if mathematics and physics are in fact comprised of synthetic a priori judgments, and if mathematics and physics are “apodeictically certain,” then the possibility of synthetic a priori knowledge is a foregone conclusion. And if synthetic a priori knowledge is actual in mathematics and physics, then recognizing how it is actual for those sciences should show how it is possible for other sciences—like metaphysics—that are not yet actual (275). In other words, if mathematicians and physicists can reason using synthetic a priori propositions, then so can metaphysicians. And if we can discover how it is possible for the former sciences then we will know how it is possible for the latter. The big question is: “How are synthetic propositions a priori possible?” (276). Kant says: “Metaphysics stands or falls with the solution to this problem” (276).

As stated above, Kant approaches this problem analytically by analyzing mathematics and physics to show how metaphysics is possible (263, 275). This method determines the structure of the Prolegomena. Having established his method, Kant divides the rest of his inquiry into four questions:

1) How is pure mathematics possible?

2) How is pure natural science possible?

3) How is metaphysics in general possible?

4) How is metaphysics as a science possible? (280).

Kant takes up these questions one at a time in four subsequent chapters of the Prolegomena. I will address three of these four chapters in detail below.

2. Part I of the Main Transcendental Question: How is Pure Mathematics Possible?

Mathematics is certain and actual. But mathematics, says Kant, consists entirely of synthetic a priori propositions (280). How can this be?

Kant notes that no mathematical judgments require empirical supplement; all work a priori on pure concepts (281). More importantly, he says, all mathematical judgments are synthetic. For example, arithmetic is such that one must go beyond the concepts “2” and “+” to know that “4” is equivalent to the proposition “2 + 2” (268-269).1 Geometry is such that one must know more than what “straight” means to conclude that the shortest distance between two points is a straight line (Critique, B16). But if these observations are correct, then the capacity for such synthetic a priori thought must belong to the mind. In other words, our minds are put together in such a way that they output “4” given an input of “2 + 2” (Prolegomena, 282).

Kant argues that the structures of the mind that cause us to draw “4” out of “2 + 2” and “a straight line” out of “the shortest distance between two points” are time and space, respectively. Kant gives “space” and “time” meanings that are quite different from their vernacular senses. Space, for example, is not that void which the Critique of Pure Reason occupies atop my desk, but the void it occupies inside my mind. That is to say, what I know of space (and time) is all in my head, a mold that shapes “the shortest distance between two points” into “a straight line,” a “form”—to use Kant’s term—that determines my intuitions. Without these forms, Kant argues, we would be unable to connect one “2” with another “2” for want of time, unable to connect two points for want of space. Space and time, as the forms of intuition, together comprise that according to which the synthetic constructions of mathematics are possible. But as conceptual forms, space and time are a priori, that is, they are features of my mind and are not derived from my experience. And herein lies the solution to the problem that Kant set out to answer in this chapter: “how is pure mathematics possible?” His answer:

Pure mathematics, as synthetic cognition a priori, is possible only by referring to no other objects than those of the senses. At the basis of their empirical intuition lies a pure intuition (of space and time) which is a priori. (283-284)

Mathematics is possible, says Kant, because our mind is equipped in a certain way, equipped with the forms of space and time. So if our mind is thus equipped, and if this equipment renders synthetic a priori knowledge possible for one science, and if the same equipment would render the science of metaphysics possible, then Kant has succeeded in establishing the possibility of metaphysics.

But it is established at a cost. For by interiorizing space and time Kant idealizes everything within them. That is to say, he transforms space and time and all that they contain—tables and chairs, my body, you, the Critique of Pure Reason (and even mathematical objects?)—into we know not what. Though we had naively supposed such objects to exist apart from the mind, we are now persuaded, if we follow Kant, that for all we know our mind has so distorted the world lying behind our intuitions that we are cut off from it.

Kant recognizes that this is a great price to pay for the establishing of metaphysics. But it is not so great, he argues, as the price demanded by those who think that we have no immediate access to the world outside us. Rene Descartes, for example, supposed that one could doubt the reality of the objects of the senses on the ground that these exist apart from the mind and that we have access to them only mediately (293). David Hume supposed that one could doubt the reality of cause and effect because if these exist at all they exist apart from the mind and we lack even mediate access to them. But Kant says that we have immediate access to the objects of sense precisely because these are regulated by the law of cause and effect (among others) (292). In contrast, then, to the more radical idealism of Descartes and the skepticism of Hume, Kant’s idealism is what he calls transcendental—or better, critical—idealism (293). In calling this idealism “transcendental” Kant means that it is about conditions for the possibility of ideas. It is an idealism that, he thinks, definitively answers skeptical doubts and provides a suitable ground in which a peculiar sort of metaphysics can grow.

3. Part II of the Main Transcendental Question: How is Pure Natural Science Possible?

Kant apparently builds in chapter three from the conclusion he established in chapter two—that all human experience occurs by way of the forms of space and time—toward discovering how it is that natural science is possible. His aim is to identify principles for metaphysics from an analysis of the laws of physics.

In this chapter, Kant builds upon an implication of his theory of intuition. Given that the entire natural world appears in space and time, and given that space and time are structures of the mind—forms of intuition, as he calls them—it follows that objects of experience constitute the natural world. Since we have no way of knowing what nature might be like behind our experience of it because we experience all of nature through the forms of space and time, it is only nature as we experience it that could concern us (295). Kant is primed—he seems to think constrained—having thus discovered the conformity of nature to the faculty of intuition, to attribute the laws of nature to further mental structures. More than this, Kant thinks he can determine the a priori conditions that make possible the experience of natural objects (297).

Kant seems to believe that we must be perpetually involved in the judgment of experience if experience is to be more than an undifferentiated stream of intuitions. That is to say, if we didn’t somehow order our perceptions we would be unable to experience them as anything—they would all run together into a confused mass. Kant considers this ordering of experience to constitute a “judging” of it. Some judgment of experience is objectively/universally valid. That is, some judgments are such that others must necessarily (if they are reasonable) agree with them. This necessary agreement indicates an objective ground that—given the ideality of the objects of experience—must be located in the structure of the human mind in what Kant calls the faculty of understanding (to distinguish it from the faculty of intuition) (298). And this indicates to Kant that the structure of the human mind corresponds to the structure of judgment in general, such that an analysis of judgment can disclose the structure of the faculty of understanding (302). The structures—or “moments”—of judgment correspond to what Kant calls the pure concepts of the understanding. These are categories under which we must subsume our perceptions of natural objects if we are to experience them as anything, drawers in which we file the deliverances of the senses to resolve them from chaos into order: substance, cause, necessity, limit, unity, reality, and etc. (302-303). Experience, then, is a product of these drawers and the ordered files inside them.

Furthermore, because nature simply is the totality of the objects of experience, and because experience is owed to the ordering of our perceptions by which we render universally valid judgments regarding causation and the like, it is clear that the rules of judgment are equivalent to the laws of nature. And this answers the question Kant presented at the head of the chapter: “how is pure natural science possible?” To put the answer more succinctly: natural science is possible because our understanding is structured so as to order the stream of perceptions, this ordered stream being all the objects of experience collectively called nature (306).

Embedded in this answer is Kant’s response to Hume’s argument concerning causality. Hume argued that it is impossible to understand causation by way of experience. Kant turns Hume on his head and argues that we understand experience by way of causation—that is, the concepts of the understanding (e.g., causation) precede and make possible the experience. In Kant’s famous words: “they are not derived from experience, but experience is derived from them” (314). So while Humean skepticism was widely regarded as a threat to natural science, Kant establishes the sciences with the words: “the understanding does not derive its laws (a priori) from, but prescribes them to, nature” (320).

In fact, all of experience is derived from the forms of intuition and concepts of the understanding for Kant, and it is this discovery that makes his special brand of metaphysics possible (313). The world is thereby divided into two parts: phenomena and noumena: nature and whatever lies behind nature: the objects of sense and those things in themselves (314). Concerning the former class (the phenomena) absolute certainty is attainable because they are formed and categorized by our intuition and understanding; concerning the latter (the noumena) absolutely nothing can be known. We will see how this plays out in the sections that follow.

4. Part III of the Main Transcendental Question: How is Metaphysics in General Possible?

In this chapter Kant describes metaphysics as he thinks it appears on the other side of his critique. It is a severely truncated metaphysics—one that can claim no knowledge about anything that lies behind experience—but a very practical metaphysics just the same.

Metaphysics, says Kant, has properly to do with pure rational concepts in addition to concepts of nature. Pure rational concepts, however—as we’ve learned from the preceding chapters of the Prolegomena—cannot be discovered nor confirmed by experience, and there is therefore nothing to guard against their being “mere chimeras.” Metaphysics proper, in other words—if construed as knowledge concerning that which lies behind experience—is impossible. But, says Kant:

This part of metaphysics…is precisely what constitutes its essential end, to which the rest is only a means…. (327)

But again, Kant argues that the pure concepts of the understanding cannot be divorced from the objects of experience, treated as mere logical functions, and thereby applied to such problems as the immortality of the soul or the existence of God. They cannot be applied to such problems because God and the soul, if these would in themselves be objects of knowledge, must be regarded as noumena. The objects of the natural world can be described exhaustively and accurately using the forms of intuition and the categories of understanding, because natural objects—that is, things as we experience them—are functions of those forms and categories. But God and the soul cannot reasonably be regarded as creatures of the understanding that survive the dissolution of the understanding. So even if the consideration of such matters constitutes the essential end of metaphysics, metaphysics can tell us nothing about them (328-329).

Kant’s way out of this impasse is to refashion metaphysics such that—though it cannot yield knowledge about the noumenal reality of God and the soul—can and does provide practical guidance by way of demonstrating the possibility and practical necessity of reasoning as if God and immortality are realities. In this, Kantian metaphysics acknowledges the boundary between the two worlds that Kant has identified—the noumenal and phenomenal—and so does not attempt to penetrate beyond it, but restricts itself instead to it—that is, it restricts itself to the relations that reason can discern between the two worlds (355).

At this point I will leave the Prolegomena behind in favor of another work of Kant’s, in which he investigates one such boundary area toward establishing a natural religion within the limits set by pure reason.


Religion within the Boundaries of Mere Reason

I. Concerning the Indwelling of the Evil Principle Alongside the Good

Kant explicitly sets out to accomplish two major tasks in the first chapter of Religion Within the Boundaries of Mere Reason: 1) to show that the possibility of radical human freedom is thinkable even if the how of its actuality is not thinkable, and 2) to reveal a manner in which good and evil principles might coexist within humanity. He is, it seems, concerned to establish these possibilities out of a sense of duty. It is Kant’s duty—if not his destiny—to clear the grounds for an affirmation of true morality and thereby breathe logos into the chaos of his day. The creation of order under law is Kant’s principal end, such that the aim implied in his title (to place Christianity within the limits of pure reason) and stated explicitly in the prefaces (to unify faith and reason by defining religion in terms of morality (6:8, 6:13)) is but a means to this end. (Page numbers given for Religion Within the Bounds of Mere Reason refer to marginal page numbers of the Cambridge edition translated by Wood and Di Giovanni.) Kant thinks that popular religion contributes to disorder but that it can contribute to order if properly purified, and so sets out to transform revealed religion into natural religion. Toward these ends Kant treats of freedom and the coexistence of good and evil within the human being.

Kant clearly believes that it is incoherent to speak of morality apart from radical freedom. If moral goods and evils exist, then they exist because of the activity of moral agents, agents who are not mere links in causal chains but are themselves originators of causal chains. Kant does not explore the possibility that moral agents and morality do not exist because, as he sees it, practical reason requires that one think and act as if they exist even if they do not. He is therefore both concerned and satisfied to establish the possibility of human free agency.

Kant tries to establish this possibility by separating out two kinds and realms of causation. Insofar as human beings belong to the natural world—that is, to the totality of the objects of sense—human behavior is inevitably cognized with the categories of cause and effect. Our minds determine this—as Kant argued in the Critique and Prolegomena—through the concepts that comprise the faculty of understanding. It is therefore inevitable that we ascribe a prior cause to any effect produced through a human agent in time; our reasoning about human behavior is unavoidably deterministic (6:21, 6:39-40). But Kant also recognizes noumena behind human phenomena. The noumenal human agent is the human agent as it is in itself, apart from the forms of intuition and categories of the understanding that make it into something we can think about—apart, that is, from space and time and natural causal law. Though nothing can be known about the noumenal human per se, something can be said about the relation that it bears to the phenomenal human (6:21-22). It is in this boundary that Kant finds room to speak of human freedom.

Kant suggests the possibility that noumenal human beings might make free choices outside of time that manifest phenomenally as caused behaviors. Though human actions must be experienced under the form of time, and though events that are constantly conjoined in time must be cognized as causes and effects through the category of causation, Kant appears to suggest that we might choose rules or “maxims” outside of time that determine how we behave within time (6:21). If we freely choose our moral maxims outside of time, and if these determine our behavior within time, then our actions are both determined and free. In this way Kant reconciles human freedom—and thereby morals—with the metaphysical and epistemological scheme explicated in his Prolegomena.2

Having thus established the theoretical possibility of human free agency, Kant is prepared to tackle a second problem that seems to him to stand in the way of a coherent conception of morals. Kant seems to believe that it is incoherent to suppose an act or actor can be morally good and morally evil at the same time. “The human being is (by nature) either morally good or morally evil” (6:22), and to think otherwise is “contradictory” (6:25). But Kant must affirm a sense in which good and evil coexist in human beings if he is to affirm that humans are responsible for both good and evil. And though he never explicitly mentions it, Kant also seems concerned to show that humans are evil only because we have freely misappropriated the goods provided by our Creator.

I find it impossible to completely follow Kant’s proposed solution to this puzzle. As far as I can tell, Kant’s suggestion is that the moral maxims that regulate our behaviors (from outside of time) are composite—made up of “principles”—and that moral freedom is the privilege and ability to differentially prioritize and emphasize these principles, such that the resultant regulating maxim is either good or evil. Each of the pieces of the resultant maxim are good, but the overall effect of their arrangement can be a maxim that is evil, and therefore good and evil principles can coexist.

What makes a moral maxim (and the person who chooses it, and the actions that arise from it) good, for Kant, is that it gives proper place to the “moral law.” If the moral law is not prioritized in the regulating maxim, then whatever behaviors issue from that maxim are evil, no matter how lawful or good they may appear. For example, one could prioritize “stay out of trouble” to “obey the moral law,” and thereby fulfill the letter but not the spirit of the moral law and so be evil in spite of making a good show.

Though Kant fails to tell us what the moral law is in Religion Within the Boundaries of Mere Reason, it seems clear that he has in mind the categorical imperative of his Groundwork for the Metaphysics of Morals:

Act always in accordance with that maxim whose universality as law you can at the same time will. (1785, Ak 4:437)

(Page numbers given for Groundwork for the Metaphysics of Morals refer to marginal page numbers of the Yale University Press edition translated by Allen Wood.) Good actions, then, are actions performed by free agents that can be universalized without contradiction. Morally good actions are actions that are performed for no other reason than because they can be universalized without contradiction, that is, out of duty. Such actions are, furthermore, all Kant can imagine that any God worth acknowledging could want from human beings, and must therefore constitute the essence of pure religion.

At this point, Kant has provided what he thinks is an adequate foundation on which to reconstruct religion within the boundaries of mere reason, and so begins the task of commandeering various Christian themes and doctrines on behalf of a religion of morals.

Fall of Humankind

Kant begins his development of a dogmatics of rational religion by reinterpreting the Christian account of the origin of evil, otherwise known as the doctrine of the fall of humanity. He finds several things in the Genesis 3 account that correlate nicely with his thoughts on the nature of morality and freedom. He notes that Adam was created good (6:44), and finds in the description of Adam’s initial innocence an echo of his doctrine that moral evil arises from nothing more than free human decision (6:41). He rejects the notion of original sin—which he interprets as the idea that all humanity has inherited a “prior innate depravity” from Adam—because it entails that humans are not free and therefore cannot be moral. That the origin of evil is traced back to a point in time, to the first sinful choice of the first man, Kant attributes to the limitations of narrative account (6:43). But his recognition that Genesis 3 is not a piece of dry history does not prevent Kant from ascribing an impure maxim to Adam. If we are to take seriously the idea that Adam fell into sin, Kant tells us, then we must suppose that he chose to adulterate the one pure aim of morals, which is doing one’s duty (6:42).

Rebirth and Grace

In the discussion leading up to his interpretation of the doctrine of rebirth, Kant notes that divine commandments presuppose the capacity to obey: “[T]he command that we ought to become better human beings still resounds unabated in our souls; consequently, we must also be capable of it…” (6:45). He puts it more concisely elsewhere: “We ought to conform to it, and therefore we must be able to” (6:62). Kant takes this to mean that our created predispositions to goodness have not been lost, and interprets the call to turn from sin to obedience as our felt obligation to properly order and prioritize the principles that comprise our moral maxims (6:46). He cites with approval certain New Testament scriptures that speak of the turn from sin to obedience in terms of “rebirth” and “new creation.” These passages seem to him to recognize that reform cannot come gradually by way of external obedience but must come suddenly, “through a revolution in the disposition of the human being…” (6:47). Kant writes:

But if a human being is corrupt in the very ground of his maxims, how can he possibly bring about this revolution by his own forces and become a good human being on his own? Yet duty commands that he be good, and duty commands nothing but what we can do. The only way to reconcile this is by saying that a revolution is necessary in the mode of thought but a gradual reformation in the mode of sense. (6:47)

Though Kant emphasizes the role of the individual will in affecting this revolution, he does not deny that heavenly grace might also contribute something:

According to moral religion…it is a fundamental principle that, to become a better human being, everyone must do as much as it is in his powers to do; and only then…can he hope that what does not lie in his power will be made good by cooperation from above (6:52).

II: Battle of the Good Against the Evil Principle for Dominion Over the Human Being


As Kant sees it, humanity is alone able to “make the world the object of divine decree and the end of creation” (6:60). He goes so far as to suggest that the divine idea of the perfect human being is that which Christians call “the Word” and “the Son of God,” and that “only in him and through the adoption of his dispositions can we hope ‘to become children of God’” (6:61). The biblical picture of the Christ is for Kant a model for imitation, a “prototypecome down to us from heaven” after whom we may strive for the salvation of our souls through “practical faith” (6:61). Though this Christ is an object of revelation according to Christian tradition, Kant finds that Christ-as-prototype is far too real to require special dispensations:

…even if there never had been one human being capable of unconditional obedience to the law, the objective necessity that there be such a human being would yet be undiminished and self-evident. There is no need, therefore, of any example from experience to make the idea of a human being morally pleasing to God a model to us; the idea is present as model already in our reason. If anyone, in order to accept for imitation a human being as such an example of conformity to that idea, asks for…miracles and credentials, to be brought about either through that human being or on his behalf…thereby confesses to his own moral unbelief…. (6:62-63)

In this, Kant does not deny that the Christ might also be “a supernaturally begotten human being” but merely finds such an idea to be inaccessible to reason and of no practical benefit (6:63).

Heaven and Hell

The way of Christ brings salvation, according to Kant, and this salvation may be pictured with images of heaven. On the other hand, the rejection of Christ brings damnation, which may be pictured with images of hell. Heaven and hell are images of the moral and the immoral life projected into the “boundless future” (6:69). They represent the practical outcomes of the moral and the immoral life, and as such constitute “incentives” toward good action. Again, Kant does not deny that heaven and hell as popularly conceived are actualities, but argues that to assert dogmatically that they are actual serves no good purpose and transgresses the bounds of reason (6:69).

Kant goes on to develop his own interpretations of atonement, miracles, and other elements of Christian dogmatics. We are familiar enough with Kant’s approach to dogmatics through the above examples, however, and so will now skip ahead to examine the next section.

III. Victory of the Good Over the Evil Principle, and Founding the Kingdom of God


In the first part of this chapter Kant develops his doctrine of the church. Though he initially prefers to use cumbersome terms like “ethical community” and “ethico-civil state” (6:94-9), it is clear that he is referring to the church stripped down to what he thinks are its reasonable, moral essentials (6:101).He looks to the church (thus stripped) for a safe haven from the temptations to shirk duty that inevitably come through worldly associations. The church, then, is a community of men and women who embrace the same moral maxim and can therefore aspire to growth through common action (6:97). It is a society free from external constraints, because such constraints contradict the freedom that is essential to morality by competing with the call to duty for duty’s sake (6:95-96). Because unadulterated duty is the incentive that binds the church together, and because it is impossible to perceive motives for the appearance of duty, the church proper is not visible (6:101). As invisible, the church must be united by a public lawgiver who is also not visible, a legislator who issues his law internally. Kant writes:

…only such a one can be thought of as the supreme lawgiver of an ethical community, with respect to whom all true duties, hence also the ethical, must be represented as at the same time his commands; consequently, he must also be one who knows the heart, in order to penetrate to the most intimate parts of the dispositions of each and everyone and…give to each according to the worth of his actions. But this is the concept of God as a moral ruler of the world. (6:99)

Though the church proper is invisible, Kant does think it important to provide criteria by which the likeness of the church might be recognized, so that it can display the “kingdom of God” to the world (6:101). The true church, according to Kant, will exhibit: 1) universality in its principles, 2) union under exclusively moral incentives, 3) free association, 4) unchangeableness.

Because claimants to the title of visible church already exist within Christianity, Kant asserts that the relation of visible to invisible church is formally one of subordination (6:110-113). He also envisions an historical process whereby this formal relationship might become visible (6:121-122). Kant distinguishes between “rational faith” and “historical faith” (6:103). Because historical faith prescribes arbitrary, statutory laws that tempt the true church away from its attention to duty, it must be brought under the tutelage of rational faith (6:104). To this end, the Christian scriptures must be interpreted by historical scholars and scholars of “reason.” The latter, Kant says, will separate the dross of historical religion from the pure gold of natural religion via a hermeneutical key provided for them in scripture: “Every scripture given by inspiration of God is profitable for doctrine, for reproof, for correction…” (I Tim. 3:16). As Kant reads it this means: “All scripture must be adapted for the moral improvement of human beings” (6:112). Through these means, a universal religion of mere reason will gradually grow out of and overtake ecclesiastical or historical religion. Kant writes:

…in the end religion will gradually be freed of all empirical grounds of determination, of all statutes that rest on history and unite human beings provisionally for the promotion of the good through the intermediary of an ecclesiastical faith. Thus at last the pure faith of religion will rule over all, ‘so that God may be all in all.’ (6:121)

Having adequately exposed its essentials, I here end my exposition of Religion Within the Boundaries of Mere Reason, and go on to consider Kant’s impact, through this book, Critique, Prolegomena, and other works, on subsequent theology.


Theology after Kant

In spite of Kant’s incredible ambition, relatively few of the details of his metaphysical work continue to inform modern theology. But what does continue to inform is a prism through which any would-be theological light must pass. For this reason, anyone who would do philosophical theology or understand the origins of contemporary theological options must know Kant.

Kant is said by some to be the most important of the developers of essentialist approaches to religion (Capps, 5). Essentialist approaches were especially popular during the Enlightenment, which, as noted above, was a period marked by the rapid advance of “reason” and “science” into every avenue of human life. In Religion Within the Boundaries of Mere Reason we saw that Kant reduced religion to morality. Religion, though ostensibly about God and perhaps even in need of a God, really has to do with human beings and their duties to each other, as Kant saw it. This “turn to the subject” or to “the natural” is a direct consequence of Kant’s conclusion—expressed in the Prolegomena and the Critique of Pure Reason—that noumena and phenomena are kept utterly separate by the nature and limits of human reason (Capps, 9). It was therefore both possible and appropriate to identify the perceived needs of humanity with the commands of God, reclaim through reinterpretation whatever themes could be adapted to promoting the true purpose of religion, and excise the rest. Many theologians since Kant have followed his pattern.

Not all who followed Kant’s pattern of reduction, reclamation, and excision agreed with his choice of essentials. But even those who thought the essence of religion was something other than morals tended to choose from among the subjects of his three critiques: the Critique of Pure Reason (about reason), the Critique of Judgment (about aesthetics), and the Critique of Practical Reason (about morals) (Capps, 10). This division of human capacities is not unique to Kant, but he has certainly contributed to promoting awareness of it and affecting divergence along its lines.

Friederich Schleiermacher agreed with Kant that religion should be human and for humans (Schleiermacher, 4). And he also appreciated Kant’s tripartite division of the human faculties (Capps, 13). But he preferred not to identify the essence of religion with morals. Instead, Schleiermacher understood religion to be an aesthetic sensitivity or quality of feeling which for him manifested as a “feeling of absolute dependence” (Schleiermacher, 49-50).

Welch (1972, 47-48), recognizing that a significant effect of Kant’s work was to interrupt Enlightenment attempts to obtain sure knowledge of God through natural theology, outlines two possible routes for theologies that emphasized belief after Kant’s Critique of Pure Reason: 1) attempt to bridge the Kantian divide by way of an alternate metaphysic or otherwise do natural theology that takes that divide into account (as in neo-Thomism), or 2) make a principled appeal to an arbitrarily selected source of revelation as that which penetrates the divide (as in Barth). Both of these paths were followed and continue to be followed by many theologians.


Concluding Remarks

In this paper I provided some historical background to Kant and his thought, and presented detailed expositions of two of his works toward better understanding his impact on philosophical theology. Though it is impossible to do justice in so few pages to as influential a thinker as Immanuel Kant, I hope that I have at least given my readers a good introduction.



Brooke, John Hedley, 1991, Science and Religion: Some Historical Perspectives, Cambridge University Press, 422 p.

Capps, Walter H, 1995, Religious Studies: The Making of a Discipline, Fortress Press, Minneapolis, 368 p.

Guyer, Paul, and Wood, Allen, 1998, Introduction to the Critique of Pure Reason, Cambridge University Press, p. 1-77.

Immanuel Kant, 1996, Religion Within the Bounds of Mere Reason, translated by George di Giovanni, Cambridge University Press, p. 41-215.

Immanuel Kant, 1998, Critique of Pure Reason, translated and edited by Paul Guyer and Allen Wood, Cambridge University Press, 785 p.

Immanuel Kant, 1977, Prolegomena to Any Future Metaphysics, translated by Paul Carus, revised by James Ellington, Hacket Publishers, 136 p.

Immanuel Kant, 2002, Groundwork for the Metaphysics of Morals, translated by Allen Wood, Yale University Press, p. 1-79.

Scruton, Roger, 1982, Kant: A Very Short Introduction, Oxford University Press, 141 p.

Welch, Claude, 1972, Protestant Thought In The Nineteenth Century, Yale University Press, 325 p.



1 I am not at all confident that I have understood Kant on this point.

2 I am not confident that what I have written in this paragraph is true to Kant.

Immanuel Kant (1724-1804)

Xiang He and Matt McLaughlin, 1998

Life (Xiang He)

Immanuel Kant was the five feet tall monument of the Enlightenment period as well as the 50 miles long bridge between continental rationalism and British empiricism. He seemed to have remained sane to the last minute of his life when he concluded "Es ist gut" (It is good). Although a bachelor (who was an unmarried man), Kant nevertheless fathered generations of philosophers to come.

Kant was born at five o’clock in a Saturday morning on April 22, 1724, at Königsberg, East Prussia. His father was an upright and hardworking saddler. His mother, an uneducated and yet intelligent woman. Both were devoted followers of the Pietist movement. At age eight Kant attended at Collegium Fridericianum, a local pietist school, where he acquired not only his love for the Latin classics, but also his distaste for religious emotions. For the rest of his life he would avoid any activities which involved praying or hymn singing.

In 1740 Kant entered the University of Königsberg. Influenced by Knutzen (a young professor who was born poor and spent his whole life in Königsberg), Kant switched his interest from philology and the classics to science and philosophy and started reading Isaac Newton and Christian Wolff.

In 1746 the death of his father forced Kant to withdraw from the school. For the next nine years he worked as a family tutor. The year 1755 saw him complete the degree at the university and find a job as a lecturer (Privatdozent). From 1755 to 1770, Kant enjoyed the pleasure of lecturing on many subjects as well as suffered the disappointment of failing twice to secure a professorship at Königsberg. During this period he was becoming increasingly critical of the Rational Philosophy represented mainly by Leibniz and Wolff.

At the ripe age of 46, Kant was finally appointed professor of logic and metaphysics. After delivering the Inaugural Dissertation, which already included many of his mature thoughts, Kant rested his hand, if not his brain, for about 11 years. He was, according to some scholars, using this time to reflect on David Hume’s empiricism and to "clarify his position with regard to Hume." (Goldmann 1971, 103-104)

The volcano of Kant’s critical energy erupted in 1781 with the publication of the Critique of Pure Reason. Within years the Critique of Practical Reason (1788) and the Critique of Judgment (1790), together with many other important works, including Religion within the Limits of Reason Alone (1793), followed. By this time Kant had established his reputation as an epoch-making philosopher.

Unfortunately, he was also establishing his old age and weak health. He retired from the university in 1796. In his last years Kant was planning to write another substantial philosophical work, but he never finished it. The notes were later published as Opus Postumum. On February 12, 1804, Kant died in the same city where he was born one era ago. (Stephen Körner wrongly moved his death date to February 28; see Korner 1955, 222.)

The Critique of Pure Reason (Matt McLaughlin)

The problem faced by Kant and his contemporaries was how to justify knowledge attained independently of experience. Hume had argued that because all knowledge began in experience, such a justification was impossible. Kant’s philosophy, called transcendental or critical idealism, provides an answer to Hume’s purely negative conclusion by offering a new hypothesis: the mind plays an active role in experiencing objects. In the Critique of Pure Reason, Kant explores the details of this hypothesis of the mind and its ramifications for knowledge in mathematics, natural science, and metaphysics.

The Classification of Judgments

Kant frames his critical philosophy within a classification of judgments. First, each judgment is either analytic or synthetic. In an analytic judgment, the predicate is already contained in the subject, and therefore these judgments merely elucidate the meanings of terms (e.g., "all bachelors are unmarried males"). To deny an analytic judgment would create a logical contradiction. Synthetic judgments, by contrast, add to the concept of a subject a predicate not contained in it. These judgments are informational, supplying new knowledge of the subject (e.g., "this bachelor is European"). The denial of a synthetic proposition does not imply a logical contradiction.

Kant further distinguishes between a priori and a posteriori judgments. A judgment is a priori if it is logically independent of all experience (e.g., the proposition that 7+5=12). The criterion for such judgments is necessity (in the sense that they are indispensable for all thinking (Körner 1982, 25)) and strict universality. Judgments that logically depend on experience are a posteriori. Empirical judgments are of this type.

All analytic judgments are a priori because, by virtue of logical necessity, they fit the criterion of necessity and strict universality. All a posteriori judgments are therefore synthetic. For Kant, the interesting question is the existence of synthetic a priori judgments. Against the empiricists, Kant argues that synthetic a priori judgments exist, and that they constitute a great part of mathematics, a portion of natural science, and all of metaphysics proper. Moreover, their use does not lead to "mere delusion," as Hume argued. The task of the critical philosophy is to justify this claim by answering the question, "’How are synthetic judgments a priori possible?’" (Kant 1945, 12).

Kant’s "Copernican Revolution"

Kant felt that his "Copernican revolution" provided the answer to this question. Kant’s revolution involved the recognition that objects actually conform to the operations of the mind, rather than the mind conforming to objects, as empiricists supposed. Because these operations or forms of the mind precede the experience of any object, they are a priori. Therefore, Kant conjectures, synthetic a priori judgments that describe the content and structure of the mind’s forms could exist. Much of the Critique of Pure Reason is an inquiry into these forms and the synthetic a priori judgments that describe them.

The Transcendental Aesthetic

The Transcendental Aesthetic discusses the mind’s contribution to the faculty of sense and the synthetic a priori judgments made possible by this contribution. According to Kant, the subject brings to sensation the two pure (or a priori) forms of intuition, space and time. He gives many arguments for the a priori nature of space and time, one of which is the following: if space and time were abstracted from perception (i.e., a posteriori), then one could imagine a representation independent of them. Because one cannot, they must not be abstractions from perception, but must be a priori brought to sensation by the subject. Therefore, all sensations must be given to the subject’s intuition in terms of space and time.

The Possibility of Pure Mathematics

The question of synthetic a priori propositions contains the question, "‘How is pure [or a priori] mathematical science possible?’" (Kant 1945, 13). Kant states that the answer to this question lies in the a priori nature of space and time. Pure mathematics is possible because it describes the a priori forms of space and time, and therefore can construct its concepts a priori. Geometry is based on the intuition of space, and arithmetic attains its concept of numbers by the successive addition of units of time.

The Transcendental Analytic

In the Transcendental Analytic, the first part of the Transcendental Logic, Kant discusses the a priori elements of the faculty of understanding. Kant calls these elements the "pure concepts of the understanding" or "the categories." Like the forms of pure intuition, space and time, the categories are not abstracted from perception, but are contributed a priori to experience by the subject. Kant states that there are twelve categories, each derived from a different logical form of judgment (see Table 1).

Logical Forms of Judgments
correspond to …
Categories of the Understanding
I. As to Quantity I. Quantity
Universal Unity (Measure)
Particular Plurality (Quantity)
Singular Totality (Whole)
II. As to Quality II. Quality
Affirmative Reality
Negative Negation
Infinite Limitation
III. As to Relation III. Relation
Categorical Substance
Hypothetical Cause
Disjunctive Community
IV. As to Modality IV. Modality
Problematic Possibility
Assertoric Existence
Apodeictic Necessity

Table 1: The Forms of Judgment and Categories of the Understanding

Kant feels that the importance of the categories lies in the difference between judgments of experience, which have universal objective validity, and judgments of perception, which have subjective validity only. The latter do not require the application of a category, but only the logical connection of a manifold of perceptions in the subject. The former, on the other hand, do require the application of "special concepts originally generated in the understanding [i.e., the categories]" (Kant 1977, 41). The application of categories confers objectivity on otherwise subjective judgments.

Kant justifies the preceding assertion by the Transcendental Deduction of the Categories. The Deduction attempts to prove that the application of categories is a necessary condition of the possibility of all (objective) experience. The proof follows from the existence of what Kant calls the "transcendental unity of apperception." This unity is the self, the I think that must exist in order to unite the manifold given in perception into a concept of an object. According to Kant, the unity of pure apperception is implied by the possibility of objective experience. And the self-consciousness of this unity implies that the categories are necessary for experience.

The categories are related to perceptions by the imagination. The imagination achieves this synthesis through the use of schemata, which specify the production of images and which pick out categories as being applicable to perceptions. (Wildman Lecture, 11/04/97). To have reference to perception, then, all concepts must have schemata; in other words, they must be schematized. This includes the Categories. Kant schematizes the categories in terms of time (‘being in time’ is the only thing that all objects of experience, including the empirical self, have in common (Körner 1982, 73)) and comes up with four divisions, corresponding to the four classes of categories (for a discussion of these, see Körner 1982, 73-74). In this schematized form, the categories can be rightly applied to perceptions.

Kant concludes the Analytic with a discussion of the synthetic a priori principles, rules that allow for the possibility of knowledge by governing the proper application of categories to objects. He derives the four sets of principles from the categories, each set corresponding to a different category class (Table 2). Kant groups the first two classes together as the "mathematical" principles, and the last two as the "dynamical" principles. The two classes differ because only the former justify the application of mathematics to appearances and allow us to predict properties of future perceptions (Körner 1982, 82).

Categories of the Understanding
correspond to…
Synthetic a priori Principles
I. Quantity I. Axioms of Intuition
II. Quality II. Anticipations of Perception
III. Relation III. Analogies of Experience
IV. Modality IV. Postulates of Empirical Thought in General

Table 2: Categories of the Understanding and Synthetic A Priori Principles

The Possibility of a Pure Natural Science

The question of synthetic a priori propositions also contains the question, "'How is pure natural science possible?’" (Kant 1945, 13). The answer lies in the existence of synthetic a priori principles. According to Kant, synthetic a priori principles are at the same time universal natural laws that can be known a priori. The collection of these principles constitutes a system of nature that may "in strictness be called the universal and pure natural science" (Kant 1977, 49). Hence, pure natural science is possible, and it is equivalent to the set of synthetic a priori principles.

The Phenomenal and Noumenal Worlds

One ramification of Kant’s philosophy is the distinction between appearances (phenomenon) and things-in-themselves (noumenon). The forms of sense (space and time) and of the understanding (the categories) allow the subject to have objective experience of the phenomenal world. However, because the subject must necessarily perceive reality through the "lenses" of these forms, he or she can never experience the thing-in-itself (which may be independent of these forms). Thus, knowledge of noumenal reality is impossible. The distinction between phenomenal and noumenal reality becomes crucial for Kant’s discussion of metaphysics in the Transcendental Dialectic.

Transcendental Dialectic

The Transcendental Dialectic deals with the error that arises when the categories of the understanding are applied to ideas. The ideas are notions that are neither derived from nor applicable to experience. They are the a priori concepts of reason, which is the faculty of mediate or syllogistic judgment. According to Kant, the ideas arise when reason proceeds upwards through syllogisms to discover the unconditioned premises from which all other premises derive. The three unconditioned premises that arise out of this process (corresponding to the categorical, hypothetical, and disjunctive forms of syllogisms) are the "subject which cannot be employed as a predicate," the "presupposition which supposes nothing higher than itself," and an "aggregate of the members of the complete division of a concept" (Pu. R. 203). These three unconditioneds give rise to the ideas of the self ("the absolute unity of the thinking subject"), the world ("the absolute unity of the series of the conditions of a phenomenon"), and God ("the absolute unity of the condition of all objects of thought in general") (Kant 1945, 209).

Illusion arises, according to Kant, because reason assumes that the process of inferring from conditioned premises to an unconditioned premise can be given in completion in experience (called the principle of pure reason). Because, says Kant, this assumption is invalid, the unconditioned premises, and therefore the ideas that relate to them, can never be given in experience. Any attempts to treat the ideas as objects of possible experience to which categories apply will fail. Kant claims that it is the failure to recognize this that has led to the illusions of metaphysics, specifically in the fields of rational psychology, rational cosmology, and rational theology.

The illusion of rational psychology, what Kant calls the "logical paralogism", is that it attempts to gain knowledge of the pure self by applying the category of substance. According to Kant, this use of the category of substance is illegitimate because categories only apply to objects of experience, and the pure self as an idea cannot be an object of experience. Therefore, proofs that the pure self is a simple substance are doomed to failure.

The illusions of rational cosmology lead to the four antinomies of pure reason. The antinomies arise from the specious application of the categories to the idea of the world. The first antinomy, corresponding to the category class of quantity, has for its thesis, "The world has, as to time and space, a beginning (limit)," and antithesis, "The world is, as to time and space, infinite." The antinomy of quality has for its thesis, "Everything in the world is constituted out of the simple," and antithesis, "There is nothing simple, but everything is composite." The antinomy of relation posits, "There are in the world causes through freedom," and its antithesis, "There is no freedom, but all is nature." Finally, the antinomy of modality has for its thesis, "In the series of world-causes there is some necessary being," and antithesis, "There is nothing in the world, but in this series all is contingent" (Kant 1977, 80).

Basing his arguments on traditional metaphysical assumptions, Kant produces what he feels are valid proofs for each side of the four antinomies. To avoid these antinomies, Kant states that his own critical position must supercede traditional metaphysics; specifically, philosophy must recognize the distinction between the phenomenal world and noumenal world. In the mathematical antinomies (the first two), this distinction amounts to a rejection of both the thesis and antithesis. For instance, in the first antinomy both sides of the argument assert a magnitude to space and time that is beyond our possible experience. But this is to treat time and space as applicable to a thing-in-itself (namely, the world outside of our experience), when in fact they are mere modes of representation, and thus only applicable to experience. The mathematical antinomies are resolved, then, by noting the illusion that lies in representing an appearance as an object-in-itself.

In the dynamical antinomies (the last two), the differentiation between the phenomenal and noumenal worlds allows the contentions of both the thesis and antithesis to be compatible. The antinomy of relation is solved if it is supposed that natural necessity refers to objects of appearance and freedom to things-in-themselves, and therefore both kinds of causality can be admitted. Similarly, the antinomy of modality is solved by distinguishing a cause within the phenomenal world to a cause of this world. Both the thesis and antithesis can be reconciled, then, because each uses cause in a different sense: the antithesis can be true in relation to the schematized category of cause, while the thesis can be true in relation to a causality "of another kind and according to another law" (Kant 1977, 87).

The illusion of rational theology comes from assuming God’s existence. For Kant, the very notion of God (the Ideal of pure reason or transcendental Ideal) involves an infinite aggregate of perfections given in completion. But the completion of an infinite aggregate can never be given in experience, according to Kant, and therefore God’s existence cannot be an object of knowledge (Körner 1982, 119).

Kant continues his critique of rational theology by attacking the three speculative proofs of God’s existence: the ontological, cosmological, and physico-theological arguments. The ontological argument attempts to prove God’s existence from the very idea of God. Kant feels that this proof fails for two reasons. First, if one denies both the subject (God) and predicate (existence), no contradiction arises. Second, existence is not a real predicate, so no matter what a concept logically implies, "it is necessary to go beyond it, if we wish to predicate existence of the object" (Kant 1945, 336).

The cosmological argument moves from the existence of something to the existence of God. Kant lists many reasons for its failure, one being that it attempts to apply the category of cause to the idea of God (the same strategy that produced the dynamical antinomies). The physico-theological or teleological proof argues that the "constitution and disposition" of the world demand God as an explanation (Kant 1945, 347). The problems with this proof are legion; the most obvious is that one cannot argue from an experience of the world to the idea of God, which is necessarily independent of experience. The best this argument can do is to prove the existence of an architect of the world, not a creator or an all-sufficient being.

Despite Kant’s pessimism towards ideas as objects of experience or speculative thought, he does feel that ideas have a legitimate function in thinking. Kant says that the ideas can be used as "regulative." That is, the ideas of self, world, and God may be treated as if they were true in order to direct "the understanding to a certain aim" and to give concepts "the greatest possible unity combined with the greatest possible extension" (Kant 1945, 361). If used heuristically, then, these ideas provide the possibility for completeness and unity of experience.

Also, the ideas have a role in practical reason. The use of the ideas in this domain of reason is described in Kant’s next Critique, the Critique of Practical Reason.

The Critique of Practical Reason (Xiang He)

In the first Critique Kant mainly dealt with the epistemological question "what can I know." As a result of his denying the validity of speculative metaphysics, the positions of religion and morality seemed to be in danger, which, however, was not Kant’s intention. In 1785 Kant wrote a short but important essay, the Foundation of the Metaphysics of Morals. Three years later, the second Critique appeared. For Kant, the question now was "what ought I to do" based on "what I can know."

The Critique of Practical Reason consists of two unbalanced parts, namely the long "Doctrine of the Elements of Pure Practical Reason" and the short "Methodology of Pure Practical Reason." Part one is again divided into two books, one "Analytic" and the other "Dialectic." Kant thought of practical reason as the rational faculty of human action. In each human action there are two "things" at work, the will and the inclination. The latter is caused by human desire, the former by the a priori idea of freedom. The moral situation thus for a human being is that on the one hand the will is free, on the other hand there are rules and laws to follow and obey. Kant put this situation between the two worlds he had established in the Critique of Pure Reason. A purely rational person would act in harmony with the principle of autonomy in the "noumenal" world so that to this person the notion of morality would have no meaning. Similarly a purely sensuous person would act according to the laws of natural necessity in the "phenomenal" world so that to this person too the notion of morality would be meaningless. A normal person, unfortunately, is both rational and sensuous, hence this dilemma.

According to Kant, morality has to presuppose freedom in order to be meaningful. Since freedom cannot be experienced directly in the phenomenal world, it must belong to the "noumenal." Kant regarded the "noumenal" world as the practical ground for ethical behavior; he saw in it the possibility of posing a moral categorical imperative. Different from the end-oriented "hypothetical imperative," the categorical imperative is unconditional: Act as if the maxim of your act can at the same time by your will become a universal law. This same idea can be put into the "practical imperative": Treat persons as ends in themselves, and never as means only. For Kant, the only good thing in the world is the good will which takes laws only from itself. If one pursues the good not for its own sake but for some other benefits, one becomes heteronomous and loses freedom.

Kant conceived of three postulates of practical reason that are required by morality. Besides freedom, the other two are the immortality of the soul and the existence of God. Kant argued that these beliefs, even though dismissed in the Critique of Pure Reason as unknowable objects beyond human sense experiences, are nevertheless essential in human moral life.

In the conclusion of the second Critique, Kant wrote: "Two things fill the mind with ever new and increasing admiration and awe, the oftener and more steadily they are reflected on: the starry heavens above me and the moral law within me." The last phrase is inscribed on his tomb.

The Critique of Judgment (Xiang He)

The Critique of Judgment is generally regarded as a series of appendixes to Kant’s earlier Critiques. In this book Kant introduced the notion of "judgment" as different from and in between "understanding" and "reason." He believed that it must therefore have its own a priori principles.

The work has two parts dealing with the ‘Critique of Aesthetic Judgment" and the "Critique of Teleological Judgment" respectively. In part one Kant wanted to differentiate aesthetic judgments from moral judgments and from scientific judgments. An aesthetic judgment, say, this flower is beautiful, has two layers of meanings. It is not only a personal feeling, it also claims to be universally valid. That is, the speaker also thinks that the flower is beautiful to everyone else. However, Kant argued, the judgment is not cognitive. No certain knowledge about the flower has been given to us through this judgment. Kant interpreted an aesthetic judgment as a result of the harmonization between the observer’s imaginative grasp of the object and his or her understanding of it.

In part two Kant focused his attention on teleology. His major concern was that the mechanical principles offered by the physical sciences couldn’t satisfactorily explain the existence of organic bodies. Yet to suggest that there was a purpose in nature as manifested in organic bodies ran the risk of suggesting a supernatural designer, a risk Kant definitely would not like to take. What Kant resolved to do was somewhat peculiar. He first admitted that teleology could be used to explain certain phenomena, but then emphasized that the organic bodies should be thought of only "as if" they were designed!

Kant’s Influence on Philosophy (Xiang He)

In 1784, to the question of "what is Aufklärung," Kant answered: "Have courage to make use of your own intellect!" This is precisely what Kant himself did, as a philosopher, as a freethinker. His work on epistemology, ethics, religion, and so on so forth, referred to collectively as Kantianism, formed the grand beginning of German Idealism, which would bloom in full in the absolute idealism of Hegel. His critical method, terms, categories, etc., forever changed not only the way philosophers do philosophies, but also the way people look at the world.

Nowadays the term "Kantianism" no longer designates Kant’s thoughts only, it has been expanded to include the many works of later scholars who are inspired by Kant. Kant’s great influence can be seen in the diversity of positions his intellectual successors have taken, some on the phenomenal side, some on the noumenal one, some both, some none. From early Kantianism to Neo-Kantianism to contemporary Neo-Kantianism, it seems the soul of Kant is immortal.

Kant’s Influence on Theology (Matt McLaughlin)

Kant’s legacy for subsequent theology has both a negative and positive aspect to it. Negatively, Kant’s critique of speculative reason extended Hume’s criticism of traditional natural theology by emphasizing that humans can have no speculative knowledge about noumenal realities such as God. Positively, Kant laid the theoretical foundation for a new approach to theology that distinguished between the pure reason, which states what is, and practical reason, which states what ought to be. While theology can never say what God is, it can recognize a reasonable form of faith in God that is implied in experience (Livingston 1971, 63). For Kant, this reasonable form of faith was strongly moral in quality.

Theologians of the nineteenth and twentieth century who decided to deal with Kant’s legacy did so predominantly in four different ways (Welch 1972, 47). One was to question Kant’s restriction of speculative knowledge to phenomenal realities only (Welch 1972, 47). Hegel took this route; he identifying knowing with being and therefore argued that the knowledge of something is the thing-in-itself (Stumpf 1993, 330). To Hegel, reality is what we know about it, and thus the distinction between phenomenal and noumenal world is unnecessary.

This route was also taken by some neo-Thomists, who attempted a revised form of natural theology (Welch 1972, 47). The neo-Thomist Joseph Marechal argued that while we cannot know the Infinite Being through a concept, we can know this Being analogically. This analogical knowledge arises because we implicitly refer all objects to the Infinite Being, whose existence is supposed by the unity of concepts. (Donceel 1970, 143). Therefore, knowledge of noumenal reality can be gained analogically.

The second route taken was to accept Kant’s criticism of reason and natural theology and thereby define theology independently of them (Welch 1972, 47). This was especially the approach of Karl Barth, who rejected any philosophy or "anthropological theology" that would purport to know God outside of God’s revelation in Jesus Christ (Mueller 1972, 86). Instead, concrete knowledge of God is gained through revelation, which is initiated solely by the sovereign God. Thus, knowledge of God cannot be achieved by humanity, although it can be received by divine initiative.

The third approach, taken up by Albrecht Ritschl and his followers, was the wholehearted acceptance of both Kant’s critique of speculative reason and his emphasis on the moral as the basis for proceeding in theology (Welch 1972, 48). A more reserved acceptance of Kant can be found in some existentialist and narrative theologies. For instance, Kant’s critique of speculative reason had a profound effect on the existentialist Søren Kierkegaard, particularly in his concept of the radical contingency of existence and in his concept of God as infinite subjectivity (Green 1992, 124).

The fourth approach was to expand the faculties of the mind so as to allow for direct experience of God or the spiritual order (Welch 1972, 48). One theologian with this approach was Friedrich Schleiermacher, who located religion within the realm of "feeling" (Gefühl), or immediate self-consciousness (Welch 1972, 62). Theology, then, is the explication of these immediate religious affections. Another theologian who approached Kant in this way was Rudolph Otto. To Kant’s categories, Otto added what he called a "category of the ‘numinous’" (Otto 1958, 11). This category allows direct experience of the "awefulness" and "mysteriousness" of the holy. Finally, Samuel Taylor Coleridge took this route by expanding the faculty of reason. Coleridge viewed reason as the divine essence present in humanity, and as therefore capable of knowing super-sensuous or spiritual realities. (Howard 19??, 37).


Kant’s Principal Works in English Translation

Kant, Immanuel. 1945 [1781]. Critique of Pure Reason. B edition. Trans. by J.M.D. MeikleJohn. New York: Willey Book Co.

______. 1977 [1783]. Prolegomena to Any Future Metaphysics. Trans. by Paul Carus, revised by J.W. Ellington. Indianapolis: Hackett Publishing Company.

______. 1949 [1788]. Critique of Practical Reason, and other writings in moral philosophy. Ed. and trans. by L.W. Beck. Chicago: The University of Chicago Press.

______. 1969 [1790]. The Critique of Judgement. Trans. by J.C. Meredith. Oxford: The Clarendon Press.

______. 1934 [1793]. Religion within the Limits of Reason Alone. Trans. by T. M. Greene & H. H. Hudson. Chicago/London: The Open Court Publishing Company.

Works Cited—Books on Kant

Beck, L. White. 1960. A Commentary on Kant’s Critique of Practical Reason. Chicago: The University of Chicago Press.

Cassirer, H. W. 1970. A Commentary on Kant’s Critique of Judgment. New York: Barnes & Noble, Inc. & London: Methuen & Co. Ltd.

Goldmann, Lucien. 1971. Immanuel Kant. Trans. Robert Black. NLB.

Hume, David. 1980. Dialogues Concerning Natural Religion. Ed. R.H. Popkin. Indianapolis/Cambridge: Hackett Publishing Company.

Körner, Stephan. 1955. Kant. New Haven and London: Yale University Press.

Works Cited—Other Books

Donceel, Joseph. 1970. A Marechal Reader. New York: Herder and Herder.

Green, Ronald M. 1992. The Hidden Debt. Kierkegaard and Kant. Albany: State University of New York Press.

Howard, Claud. 19??. Coleridge’s Idealism. Boston: The Gorham Press.

Körner, Stephen. 1982 [1955]. Kant. New Haven: Yale University Press.

Livingston, James. 1971. Modern Christian Thought: From the Enlightenment to Vatican II. New York: The Macmillan Company.

Mueller, David L. 1972. Karl Barth: Makers of the Modern Theological Mind. Waco: Word Books.

Otto, Rudolph. 1958 [1923]. The Idea of the Holy. New York: Oxford University Press.

Stumpf, Samuel Enoch. 1993 [1966]. Socrates to Sartre: A History of Philosophy. 5th ed. New York: McGraw-Hill, Inc.

Welch, Claude. 1972. Protestant Thought in the Nineteenth Century, vol. 1. New Haven: Yale University Press.

Immanuel Kant (1724-1804)

Wonbin Park, 2000


Born in Königsberg (now Kaliningarad, Russia), on April 22, 1724 and died at the same place on the 12th of February 1804. Kant received his education at the Collegium Fredericianum and the University of Königsberg. Like many other great men of this period, Kant came from humble origins. His father was a saddler (harness-maker). Kant’s father married Anna Regina Reuter. Kant was their fourth child. His parents belonged to the Pietistic movement, which was a strong formative influence on Kant. Being devout Pietists, both of his parents took a firm and ethical interest in their children’s moral and spiritual development. This movement claimed the personal appropriation of religion. To his mother, religion appears to have been a matter of living faith. Kant could not lose this lively appreciation of what he owed to his mother. Once Kant explained himself to his friend, “I shall never forget my mother, for she implanted and nurtured the first seed of the good in me; she opened my heart to the influence of Nature; she awakened and broadened my ideas, and her teachings have had an enduring, beneficent effect on my life” (Cassirer, 13). However, one can claim that Kant’s thought is quite devoid of pietistic belief and behavior. “Even though the religious ideas of that time and the concepts of what they called virtue and piety were anything but clear and adequate, still they really got hold of the basic thing” (Cassirer, 17).

As a boy of eight, in the autumn of 1732, Kant entered the Collegium Fredericianum. As a bright student in elementary school, Kant excelled at classical languages. After this academic career, he showed a universal curiosity. He entered the University of Königsberg as a student in the Faculty of Theology, but he was much more interested in the study of the natural sciences, even though he did not pursue that direction. Kant began to write and embark on the career of a university teacher at thirty-one. He published one short work on the problem of physics, and he began by giving lectures on physical geography and empirical psychology.

Kant’s first book, which was published in 1747, was entitled “Gedanken von der Wahren Schatzung der lebendigen Kräfte” (“Thoughts on the True Estimation on Living Forces”). In 1755 he published his doctor’s dissertation, “On Fire” (“De lgne”), and the work “Principiorum Cognitionis Metaphysicae Nova Dilucidatio” (“A New Explanation of the First Principles of Metaphysical Knowledge”), which qualified him for the position of Privatdozent. In 1770 appeared the work “De Mundi Sensibilis atque Intelligibilis Formis et Principiis” (“On the Forms and Principles of the Sensible and Intelligible World”), in which he shows an independent system of philosophy. Kant spent his time from 1770 to 1780 in the preparation of the Critique of Pure Reason (Kritik Der Reinen Vernunft).

Although Kant’s lectures and works written in the early 1760s established his reputation as an original philosopher, he finally became an ordinary professor in Logic and Metaphysics in 1770. Eleven years after, Critique of Pure Reason appeared in 1781. The work is difficult to read, because of the combination of earlier (1781) and later versions (1787) and in German instead of Latin. Two years after this great book appeared, Kant wrote a shorter, more compact, and more readable introduction, Prolegomena to Any Future Metaphysics. Kant’s purpose is to construct a solid epistemological and methodological basis. He continued this project on ethics in Critique of Practical Reason (1788) and aesthetics in Critique of Judgement (1790). Kant’s unorthodox religious teachings, which were based on rationalism rather than revelation, brought him into conflict with the government of Prussia. In 1792, he was forbidden by Frederick William II, King of Prussia, to teach or write on religious subjects. However, he submitted his book, Religion within the Limits of Reason Alone, to the philosophical faculty of Jena University, and published it at Königsberg in 1793. In 1794, he received the following letter from the king:

Our most high person has for a long time observed with great displeasure how you misuse your philosophy to undermine and debase many of the most important and fundamental doctrines of the Holy Scriptures and Christianity; how, namely, you have done this in your book, Religion innerhalb der Genzen der blossen Vernunft, as well as in other smaller works…We demand of you immediately a most conscientious answer and expect that in the future, toward the avoidance of our highest disfavor… If you continue to resist, you may certainly expect unpleasant consequences to yourself (Greene, 34).

Although he obeyed this order for five years until the death of the king, he was a son of the Enlightenment. Kant was a strong advocate of the right and duty of every man to judge for himself in religious matters. In a famous article, An Answer to the Question, What is Enlightenment? published a few years earlier (1784), he had affirmed the motto of the enlightenment, “Have courage to make use of your own reason!” (Greene 32) In 1798, the year following his retirement from the university, he published a summary of his religious views. He died February 12, 1804.

Kant’s Philosophy: Critique of Pure Reason

1. Transcendental Aesthetic

Space and Time: Form of Sensation

The keystone of Kant’s philosophy is contained in his Critique of Pure Reason. In the Prolegomena, he sees the Critique of Pure Reason as presenting “a perfectly new science” (Kant, 1977, 7).

Why did Kant establish his study of human knowledge on the form of a priori? Giovanni Sala, who was a professor of University of München, syllogized Kant’s reason in the following way:

  1. Scientific knowledge is knowledge of the universal and necessary.

  2. But universality and necessity cannot come from experience; that is, they cannot be based on anything a posteriori.

  3. Therefore they are a priori. (Sala, 181)

In the “Transcendental Aesthetic”, Kant deals with sensibility and seeks to discover its pure a priori conditions. What does Kant mean by “pure”? He defines that “pure is independent of experience and even all impressions of the senses” (Kant, 1968, 42). Kant raises a question: are there any “pure forms of sensible intuition” through which everything is perceived ? (Kant, 1968, 67) He answers that there are such forms of pure perception-space and time. He says that if we subtract all conceptions of cause and substance, time and space still remain. All of our perceptions are determined within Here, a particular space, and Now, a particular time. Space and time cannot be conveyed through sensation. They must be presentations to let the mind (Verstand) arrange our sensations. But space and time are indivisible from our intelligence. Even if one can think of space without objects, he cannot think of the non-existence of space. Likewise, if one can think that nothing happens, he cannot think of the non-existence of time. Therefore space and time are inseparable from our intelligence. They are a priori forms of consciousness. They constitute conditions of the possibility of objects of external and internal sense (Clark, 53). The a priori space and time perception gives us universal and necessary truths. Time and space are independent of the sensation given in particular experience. It enables all minds to anticipate the form of experience.

Space and time are respectively forms of outer and inner perception. We cannot perceive anything as existing outside us except by putting it in certain space. In addition, we cannot perceive anything within us except by placing it in certain time. “Time has one dimension, different times are not simultaneous but successive just as different spaces are not successive but simultaneous” (Kant, 1968, 75). For Kant, time and space cannot be derived from experience. They are logically prior to experience.

It is important to ask at this point: Do the a priori forms of sensation extend the domain of sense-knowledge? Kant says that they do not. They affect knowledge qualitatively, not quantitatively. The data of sensation represent only the appearances (Ersheinungen) of things. Therefore all sensation is confined to a knowledge of appearance. Sense-knowledge cannot penetrate to the noumenon, the reality of the thing (Ding-an-sich). (Kant, 1968, 84, 271, 274) Kant said,

It is, therefore, not merely possible or probable, but indubitably certain, that space and time, as the necessary conditions of all outer and inner experience, are merely subjective conditions of all our intuition, and that in relation to these conditions all objects are therefore mere appearances, and not given us as things in themselves which exist in this manner (Kant, 1968, 86).

In the “Transcendental Aesthetic” Kant shows that the notion of pure mathematics is innate to the human mind. In his “Transcendental Logic” he shows that some non-mathematical concepts are also like this (Kant, 1968, 96).

Kant divides the “Transcendental Logic” in two parts: “Transcendental Analytic” and “Transcendental Dialectic”. The former deals with the application of a priori concepts. The latter deals with the improper and fallacious application of such concepts.

By analyzing a priori intuition, time and space, Kant tries to deal with transcendental analytic. “The part of transcendental logic which deals with the elements of the pure knowledge yielded by understanding, and the principles without which no object can be thought, is transcendental analytic” (Kant, 1968, 100).

2. Transcendental Analytic

Categories: Form of Understanding

Like other earlier philosophers, Kant differentiated modes of thinking into analytic and synthetic judgments (propositions). An analytic proposition shows that the predicate adds nothing to the subject, i.e., “a bachelor is an unmarried male”. The truth of this type of proposition is clear, because if we state the negation of this proposition, it makes the proposition self-contradictory. In other words, the judgment ‘All S is P’ is analytic only if the concept of class S contains the concepts of the characteristic P. If one can not find the concept of the characteristic P by analyzing the concept of S, it would be self-contradictory (Brood, 1978, 4). Such propositions are called analytic because truth is found by the analysis of the concept itself. On the other hand, synthetic propositions cannot be reached by pure analysis. For example, “Wonbin Park is a bachelor” is a result from experience of the world, and this sentence increases the given cognition (Kant, 1977, 12). According to Kant, propositions are divided into two other types. Synthetic propositions are empirical and the earlier statement depends on sense perception. On the other hand, analytic propositions are a priori. A priori statements have a fundamental validity and are not based on such perception. We can simply illustrate these distinctions with the empirical sentence “Wonbin Park is a bachelor” and the analytic sentence “a bachelor is an unmarried male”. Kant claims that analytic judgments do not advance knowledge at all, since they always make no advance beyond the data of the concepts. At the same time he claims that the synthetic judgments have no scientific value. Therefore, he proposes a third class, namely synthetic a priori judgments. Kant’s critical thesis in Critique of Pure Reason is that it is possible to make synthetic a priori judgments. According to Kant, an example would be “Every effect must have a cause.” Our concept of ‘effect’ and ‘cause’ are supplied by experience; but the universality and necessity are derived from “all our a priori endowment of the mind (Kant, 1968, 51). By synthetic a priori judgments, Kant tries to establish not only the universal, necessary features in human knowledge, but also actual conditions for possible knowledge.

Kant starts with the division of what nature offers for our knowledge and what the mind contributes to this. The status of “what nature offers” is an unorganized impression given by nature. The forms are already in the mind. Kant categorized this forms as follows (Kant, 1977, 38-46):




As to Quantity



As to Quality



As to Quantity

Unity (Measure)
Plurality (Quantity)
Totality (Whole)


As to Quality



As to Relation



As to Modality



As to Relation



As to Modality


These categories are twelve in number and each is derived from one class of judgement. These forms are directly intuited. We never experience these forms independent of our senses. Likewise, we never perceive sense data without these forms. In order to show that the categories are necessary as the forms of perception, we inquire into the relation between perception and thinking. The meaning of synthetic a priori judgements is that the judgements are synthetic because the content of them is supplied by a synthesis of the facts of experience. In addition, a priori, because the form of universality and necessity is imposed on them by the understanding, is independent of experience. In this sense, Kant says, “Thoughts without content are empty, perceptions without concepts are blind.” (Kant, 1968, 93) ‘Thoughts without content are empty’ means that, without sense data, metaphysics is an empty knowledge; ‘perceptions without concepts are blind’ means that, without categories, sense date is useless.

In order to establish necessary conditions of objective experience, objects are to be perceivable, and also thinkable. Kant’s discussion of the relationship between the unity of objects and pure self-consciousness shows that our understanding is mutually interdependent with perceiving and thinking. There are objects of experience that we perceive and think. The knowledge of objects presupposes the forms of perception (space and time), and the form of understanding (Categories). (Körner, 63) 


We can find rationalism and empiricism in Kant’s thinking. For rationalism, he tries to establish the universal, and necessary features in human knowledge. He also worked as an empiricist, in the sense that he focused on establishing the actual conditions for possible knowledge. Unlike British empiricists, Kant makes the operation of mind indispensable. What he has done is to change the Hume’s concern into the formal condition, disregard of particular subject matters. Kant shows that the relation of cause and effect can not be known from a fact in nature, but a necessary form of thought. The mind is not passive to objects, it constructs the possible experience. This is known as “Copernican revolution” in epistemology. (Philipson, 1962, 714)

Kant himself was wont to say that business of philosophy is to answer to the three questions: What can I know? What ought I to do? What may I hope for? However, he thought that the answer to the second and third depends on the answer to the first. Our duty and destiny can be determined only after a thorough study of human knowledge. Kant never denied the existence of God, immortality of soul, and the ultimate reality of matter. However, his goal was to argue that these three ideas could not add in our knowledge. All our knowledge is inevitably conditioned by our own cognitive faculties, so that we cannot know or even understand how the world would look from outside (For example, from God’s view). It is very easy to find how the negative argument of Kant’s philosophy influenced philosophical thought in Europe. The conclusion of Critique of Pure Reason is the proposition of agnosticism. We can know nothing except the appearances of things. The senses reach only phenomena. 


Kant’s Works

Kant, Immanuel. 1968. Critique of Pure Reason. Trans. by Norman Kemp Smith. New  York: St. Martin’s Press.

________. 1977. Prolegomena to Any Future Metaphysics. Trans. by Paul Carnus. Indianapolis: Hackett Publishing Company.

________. 1960. Religion Within The Limits of Reason Alone. Trans. by Theodore Greene. New York: Harper & Row Publisher.  


Broad, C.D. 1978. Kant: An Introduction. Edit. by C. Lewy. London: Cambridge University Press

Cassirer, Ernst. 1981. Kant’s Life and Thought. Trans. by James Haden. New Haven: Yale University Press.

Clark, Norman. 1925. An Introduction To Kant’s Philosophy. London: Methuen & Co.

Goldmann. Lucien. 1945. Immanuel Kant. Trans. Robert Black. London: NLB

Körner, S. 1970. Kant. Harmondsworth: Penguin Books Ltd.

Parsons, Charles. 1992. “The Transcendental Aesthetic” in The Cambridge Companion To Kant. Cambridge: Cambridge University Press.

Paulsen, Friedrich. 1972. Immanuel Kant: His Life and Doctrine. New York: Frederick Ungar Publishing.

Philipson, Morris. 1962. Foundations of Western Thought: Six Major Philosphers. New York: Alfred A. Knopf.

Sala, Giovanni. 1976. “The A Priori in Human Knowledge: Kant’s Critique of Pure Reason and Lonergan’s Insight” in The Thomist: A Speculative Quarterly Review 40 (April): 179-221.

Young, J. Michael. 1992. “Functions of thought and the synthesis of intuitions” in The Cambridge Companion To Kant. Cambridge: Cambridge University Press.

Notes on Immanuel Kant (1724-1804)

Andrew Irvine, 1998.

True religion is a vehicle for the advance of rational morality, toward the realization of an ethical commonwealth on earth. It is, thus, the recognition of all moral duties as divine commands (cf. Religion Within the Limits of Reason Alone, 142). It has nothing to do with theoretical knowledge, or aesthetic appreciation of God; neither has theology, unless to explicate just this autonomy.

Theology cannot succeed as a speculative, metaphysical science because all synthetic knowledge presupposes the conformation of objects to the forms and categories of reason by which experience is yielded. The only exception to this rule is knowledge of those forms and categories themselves—so-called synthetic a priori knowledge. Since God is not among these truths, nor among experienceable phenomena, theoretical reason is necessarily agnostic with respect to theology’s primary subject. Indeed, all knowledge of realities outside the mind is of things-as-they-are-experienced (phenomena), rather than as they are in themselves (noumena). Consequently, traditional metaphysics cannot be established as a science. A ‘Copernican revolution’ is called for: ‘The general metaphysical principles of rationalism turn out to be true when relativized into statements about the form and structure of empirical knowledge’ (from an article on Kantianism whose source I have been unable to trace as yet).

All this is a culmination of Kant’s dual philosophical inheritance:

Descartes (1596-1650)
Certainty belongs to knowledge that can be demonstrated from intuitive, self-evident starting points—not from the senses.

British Empiricism
Hume (1711-1776)
Knowledge pertains to the observable world; for that reason it is uncertain and unreliable.

Continental Rationalism
Leibniz (1646-1716)
The true object of knowledge, therefore, is an intelligible realm beyond the senses.

Kant (1724-1804)
Universality and necessity in knowledge are not due to, or descriptive of, an intelligible, rational realm inaccessible to the senses, but follow from the form or pattern of rational operations to which the phenomena have been conformed.

Although reason cannot assay the truth of religion metaphysically, it can give an ethical account of religion that neither stands nor falls on metaphysical agnosticism. This possibility lies within pure practical reason, the basis for ethical conduct at all.

Practical reason stipulates that for any deed or proposal to attain to the status of the moral it must conform to principles of universality, impartiality and rationality. Only thus does it have the aspect of binding legality, in conformity with the categorical imperative: ‘Act only on hat maxim which you can at the same time will to be a universal law.’

The ‘ideas of reason,’ namely the existence of God, freedom of the will, and immortality of the soul (which, prior to Kant’s critical revolution, were loci of metaphysical concern) cannot be resolved as either true or false. They can function only as regulative ideas for practice. Their objective/noumenal status is a matter of faith. Thus Kant ‘makes room’ for faith. However, in Religion Within the Limits of Reason Alone, Kant suggest that these ideas are logically admissible postulates for the purpose of harmonizing categorical ethics with more traditional teleological accounts of ethics. (That is, to allay concern that the perfection of the rational life might not coincide with human happiness.)

The categorical imperative does not destroy human freedom but fulfils it because it is rationally chosen self-legislation. It realizes the ideal of autonomy.

However, in Religion, Kant addresses the problem of evil with regard to the inclinations of the will. In doing so, he enriches the terms of his philosophy of religion with ethical, ahistorical transpositions of Christian notions, including grace and atonement. Indeed, external cult is accorded relevance inasmuch as traditional religion (especially Christianity) aids in providing social unity for the task of realizing an ethical commonwealth. Other religions are ‘servile’ rather than purely ethical-rational. Jesus is significant as the manifestation of a moral ideal that can be called ‘God incarnate.’ Jesus exemplifies an archetype to which all human beings can conform.

Theological possibilities after Kant:

  • Accept the moral transposition of religion (Ritschl);
  • Expand or deepen Kantianism (a) a specifically religious form of intuition (Schleiermacher? Hick)
  • (b) some religious object as a transcendental condition for any experience;
  • Refute Kant (Hegel);
  • One-up Kant (e.g. Barth—philosophy, then, can place no limit to God’s self-disclosure);
  • Conduct a research program to test hypotheses about the noumenal realm, garnering evidential (not certain) results (Wildman).

Notes on Parts of Kant's Critique of Pure Reason

Roy Smith, Boston University, 2008

As last week Todd presented up through B175, I will not attempt to recapitulate a summary of that material. I will however attempt to hit some main points in those sections, so as to make a smooth transition into the sections assigned for today. Thus the Transcendental Analytic will be quickly addressed, followed by the Second Analogy. I will show how Kant relates categories to objects of appearances, and discuss ‘the turn’ (as Dr. Neville describes) he takes in the second analogy. Last, I will discuss the main points in the section on the distinction between phenomena and noumena. I want to keep in mind two primary questions for the purpose of this presentation: First, on what basis does Kant posit the objective validity of our representations/appearances to the things-in-themselves to which they correspond? Second, how does the first Critique relate to faith in the idea of God?

Kant’s main question is how synthetic judgments are possible a priori (B19). Further, as shown below, Kant wants to discuss the relation of understanding (judgment) to intuitions (sensibility). He will then move from these faculties to the question of reason- leading to the question of whether pure reason is something that can be distinguished from the understanding. He will show that it can. In a nutshell, concepts come from the understanding and are combined by our minds with intuitions. But reason stands above the unity of understanding, and wants to push beyond our knowledge- into transcendental illusions. This is where the three key ideas (God, immortality, and autonomy- corresponding to Kant’s three questions to which his three Critiques are dedicated: What can we know? What should we do? What can we hope for? Thus the first Critique examines that which lies in the human mind prior to experience to address the question of what we can know. This is called a Transcendental Philosophy.[1]


The categories of the understanding articulate the concepts which the understanding provides for the imagination to schematize sensible/intuitive experiences of the appearances of objects. That which “precedes all data of intuition” (i.e. precedes experience), through which alone experience is possible, is transcendental apperception (A107). This acts as a “transcendental ground of unity” through which the concepts and the appearances are synthetically unified. Thus the categories are the “conditions of thinking in a possible experience”, and space and time are the “conditions for the intuition” of possible experience (A111). Importantly, this process rests upon an a priori “objective ground”, or a universal rule/law (A122). “Sensibility gives us forms (of intuition), but the understanding gives us rules” (A126). This claim leads to Kant’s assertion that the understanding is the faculty which acts as rule maker and legislator of nature. He even goes so far as to claim that nature is contingent upon our minds: “without understanding there would be no nature at all” (A127).

How does this all relate to the claims of objective validity made by Kant? The way in which he approaches “objective validity”: Kant divides elementary logic into general pure and general applied sections. Without going into great detail, I will mention that Kant wants to show that pure logic has been misused by people who have attempted to posit “objective assertions”, when it (logic) is only “merely a canon for judging” (A61). Kant wants to attempt then, in the Analytic of Concepts, an “analysis of the faculty of the understanding itself, in order to research the possibility of a priori concepts” (A66/B91). Kant sees these pure concepts as “seeds…where they lie ready, until…experience [develops them] in their clarity…liberated from the empirical conditions attaching to them” (Ibid).

Concepts lie “pure and unmixed in the understanding”, prior to experience. This is the state of the categories before they are applied to objects of appearance, or a priori (A67/B92).[2] But how can we know whether our subjective representations can be trusted with regard to the objective validity of things in themselves? Kant answers this question by appealing to what he calls a universally valid rule, which is causality. Subjective representations can be understood as objectively valid judgments in the understanding- not simply judgments “deceived by sensibility”.[3]

For Kant, the concept of causality is detailed in this way: All change is change in substances. How to determine change in substance verses change in subject (i.e. succession in objects verses succession in subjective representations- c.f. B239), is whether the change is necessary and irreversible (A198-99/B243-44). Kant first provides the analogy of a house in juxtaposition to a moving ship (A190-93/B235-38). One can move around the house in any of various ways (clockwise, counterclockwise, etc.), and the experience of change is only subjective, or experiential. However the ship (moving down the stream) is different. One can experience the change, or succession in the object, only by virtue of the movement of the object itself. The movement of the ship, if reversed, would result in a different succession. Therefore the movement of the ship has objective validity. Hence the human mind organizes experience according to a rule which makes things necessary and irreversible. [Am I the only one who sees a contradiction here?] This is an a priori rule. Appearances necessitating one another allow us to refer change to objects, within an objective time order. This is the concept of a causal relation. (c.f. Sebastian Garner 74-76) I will now closely detail the Second Analogy.


Kant begins his argument with an appeal to his first analogy, where he has shown that the “arising and perishing of [a] substance does not occur”. Therefore, “All change (succession) of appearances is only alteration…” (B233). Second, because we “perceive that appearances succeed one another, i.e., that a state of things exists at one time the opposite of which existed in the previous state”, we “really connect two perceptions in time”. This connection is attributed not to “sense and intuition”, but to “the synthetic faculty of imagination, which determines inner sense with regard to temporal relations” (Ibid). There are two different ways in which the faculty of the imagination “can combine the two states in question [two perceptions in time]:

So that either one or the other precedes in time; for time cannot be perceived in itself, nor can what precedes and what follows in objects be as it were empirically determined in relation to it. I am therefore only conscious that my imagination places one state before and the other after, not that the one state precedes the other in the object; or, in other words, through the mere perception the objective relation of the appearances that are succeeding one another remains undetermined. (B234)

So then, the question is whether or not I can trust my faculty of imagination to inform me accurately with regard to the movement of objects (i.e. reality). Is the movement I perceive in objects really occurring in the objects, or only in my imagination? Kant wants to answer this by appealing to causality. He will next discuss how to determine that which (as stated above) is at this point, still undetermined. How can we know whether the succession we perceive in objects is objectively valid (occurring in the object), or merely subjective (occurring only in the mind).

Kant says that “if the objective relation of the appearances that are succeeding one another … is to be cognized as determined”, we must first establish whether the relation between the two states can be thought so as to place one state as preceding another. (B234) His answer is yes, in accordance with the principle of temporal sequence according to the law of causality (i.e. cause and effect). This is Kant’s argument: Only a “pure concept of the understanding, which does not lie in the perception” can offer the objectivity in question. This is the case because what is needed is a concept “that carries a necessity of synthetic unity with it”. The “relation of cause and effect” is just such a concept. Why? Because the consequence of cause is effect. Cause determines effect- not subjectively in the imagination, but objectively in time. This is so because “empirical cognition” of alteration in appearances is only possible by subjecting all alteration to the law of causality. Therefore Objects of Experience are only possible in accordance with the law of the connection of cause and effect.

The House (A190ff /B236ff):

·        The apprehension of the appearance of a house that stands before me is successive.

·        The question is whether the manifold of this house itself is also successive, which certainly no one will concede.

·        As soon as I raise my concept of an object to transcendental significance, the house is not a thing in itself at all but only an appearance, i.e., a representation, the transcendental object of which is unknown…. (emphasis mine)

The Problem: How to distinguish one apprehension of an occurrence from another (A192-93/B237-38). We only perceive (empirically) that something happens (“that something or a state comes to be that previously was not”), when we have had a previous appearance not containing the current “state in itself”. A reality following an empty time cannot be apprehended. “An arising not preceded by any state of things” can be apprehended. “Empty time” cannot be apprehended. Thus “every apprehension of an occurrence is therefore a perception that follows another one.”

However, because this is the case with all syntheses of apprehension, distinguishing one apprehension of an occurrence from another becomes a problem. Kant answers this problem with the analogy of a ship moving downstream, juxtaposed with the example of the house given above.

The Ship

A precedes B, as cause to effect. B can only follow A in apprehension.
The perception of A cannot follow but only precede B.

The analogy is that of watching a ship moving downstream. Kant says that his perception of the movement downstream follows its (real) movement downstream. He cannot perceive the movement backwards. In other words, if the ship moves downstream, Kant cannot perceive that the ship is moving upstream. “The order in the sequence of the perceptions in apprehension is therefore here determined, and the apprehension is bound to it.” With the example of the house, Kant could have looked at it in varying ways (top to bottom, left to right, or in reverse of these). Therefore, with the house, there was no “determinate order” wherein the house was to be apprehended. The ship, however, offers an example wherein the objective sequence determines the subjective apprehension of its object. Therefore Kant concludes that without an objective sequence by which the subjective sequence is determined, the latter would be entirely arbitrary, and would tell us nothing about the object. In other words, the example of the ship involves a situation wherein the succession of the object demands that the connection of the manifold in the object be determined, or given to the subjective apprehension from its objective state. This is the way in which Kant arrives at the conclusion that the connection of the subjective sequence of apprehension is derived from the objective sequence of appearances. This tells us that there is a rule: that which happens must follow that which precedes the happening. This rule is evident when “I cannot arrange the apprehension otherwise than in exactly this sequence.” (A193/B238) This rule presupposes a condition for a rule; i.e. an appearance is related to some preceding point.[4]

Kant’s argument then moves through the following propositions:

When we experience a happening, we presuppose something preceding it, which follows in accordance with a rule. Because I discover this rule not in the normal inductive, a posteriori, empirical way, it is a priori, universally valid, and objectively valid (A196/B241). “The case is the same here as with any other pure a priori representations (e.g. space and time) that we can extract as clear concepts from experience only because we have put them into experience, and experience is hence first brought about through them.” (Ibid)

·        Thought concepts such as causality are only possible if we have used them in experience, causality, “as the condition of the synthetic unity of the appearances in time, was nevertheless the ground of experience itself, and therefore preceded it a priori.” (Ibid)

·        In experience, we never ascribe sequence to an object (rather than to our representations of it), unless there is a rule which makes the objective validity of sequence in the object the only conclusion we can draw. (A197/B242)

·        The way in which we posit objective validity (i.e. objective reality) to our subjective representations, is by “subjecting them to a rule; and conversely that objective significance is conferred on our representations only insofar as a certain order in their temporal relations is necessary.” (A198/B243)

·        No object is represented in our (subjective) sequential manifold representations, because therein “nothing is distinguished from anything else.” (Ibid)

·        Temporal relation is only seen in the object when:

I cannot reverse the series.

The determinate occurrence inevitable and necessarily follows from positing the preceding state.

·        Therefore, “there is an order among our representations, in which the present one…points to some preceding state as a correlate…as its consequence, and necessarily connected with it in the temporal series” (A199/B244). The preceding time necessarily determines the following time. The understanding is what allows for the possibility of a representation, by giving temporal order to appearances. This is accomplished by its assigning temporal order to appearances- a priori.

·        A perception is actual (objectively true and real), if the rule for temporal sequence (causality) can be applied to it (A200/B246).[5]

Finally, Kant discusses “the empirical criterion of a substance”, which shows itself better through action than as inactive appearance. Action, activity, and force cannot occur without substance. Thus Kant will show the source of appearances in substance. (A204-05/B250-51)

First, we infer from action to persistence of a substance causing that action. Second, effect implies changeability, “which indicates succession in time, the ultimate subject of the changeable is therefore that which persists, as the substratum of everything that changes, i.e., the substance (Ibid). Third, the concept of a substance as appearance is supported by the inference that the loci of all arising and perishing cannot arise and perish itself. This inference leads Kant to posit “empirical necessity and persistence in existence, consequently to the concept of substance as appearance.” (A206/B251) The state of a substance arises, not the substance itself. This is alteration. Substances are therefore not originated out of nothing (as in creation). Rather, they act; and because they act, they must then persist. (B252) We have no a priori concept of alteration. However, the form of alteration can be thought a priori. (A207) Kant wraps his argument up by showing that a perception is always a magnitude through all degrees. Therefore the cognizing of an a priori law (the form of alteration) in the perception is possible. Kant claims that the “empirical cognition of temporal relations” is thereby objectively valid via the law of causality.


On the ground of the distinction of all objects in general into phenomena and noumena

Kant now wants to leave the “island of the understanding”, which is the “island of truth”, “enclosed in unalterable boundaries by nature itself”. (B295) Outside of this land- the understanding- is illusion. There are two questions this section will discuss: can we be satisfied with the understanding, and on what grounds can we defend the understanding. Before these questions are discussed, Kant reviews the analytic with these points:

·        All that the understanding contains is for the purpose of usefulness in experience; thus providing the pure schema through which the understanding synthetically yields concepts to the imagination. Apperception is on one side and appearances on the other. The understanding synthetically unifies their relation in order to cognize objects of appearances. (A237/B296)

·        These a priori rules are truth, and they are the “source of all truth” (remember, Kant defines truth as the agreement of “our cognition with objects, in virtue of containing the ground of the possibility of experience, as the sum total of all cognition in which objects may be given to us”. (Ibid)

·        It is not enough to stop here. One must further ask what use the above findings yields. One such benefit is that the understanding cannot assess its own boundaries, or “distinguish whether certain questions lie within its horizon or not … [the understanding] continually oversteps the boundaries of its territory … and loses itself in delusion and deception”. (A238)

·        As a result, the understanding is only of empirical- never of transcendental- use for concepts. (B298)

·        Transcendental use of concepts entails the relation of a concept to things in general and to things in themselves. Empirical use of concepts entails the relation of concepts only to appearances, or objects of possible experience.

That the understanding is impotent for transcendental use of a priori principles (or its concepts) is shown by its logical form and need to give that form to objects of experience. Without the latter, the understanding “is entirely empty of content”. Because this process can occur only in intuition (A239), we are dependent upon experience to seek objective validity. Further, experience limits the categories.[6]

This limitation leads Kant to seek something that is not limited by sensibility (meanwhile refuting the ontological tendency to rest its arguments on negation). If there is a way of thinking without relating intuitions to objects, the said object would be a transcendental object (B304). This cannot happen, therefore the categories cannot be useful in a transcendental way. Phenomena are defined as appearances thought through the categories. Noumena are defined as things that are objects only of the understanding, that could be “given to an intuition, although not to sensible intuition” (A249). The tension here is between things as appearances, and things-in-themselves. If it were possible for us to think of “pure cognitions of the understanding” with no sensibility whatsoever, there would be a “pure and yet objectively valid” use of the categories. This would be a “world thought in spirit” (A250), or a world of noumena. This is impossible. Therefore we can only think, but never really know, things in themselves- because they could only be know without the interference of sensibility/intuition.

Sensibility is limited by the understanding, only allowing appearances, but never access to things-in-themselves: “This was the result of the entire Transcendental Aesthetic” (A252). Because appearance must presuppose a source which is not appearance (a thing-in-itself, “an object independent of sensibility”), we have the concept of a noumenon. This is only a concept, not something real, since there is only one possible intuition for us- which cannot be independent of sensibility. Thus the concept of the noumena is only “a boundary concept, in order to limit the pretension of sensibility, and therefore only of negative use” (B311). This is a concept we cannot help but think, but it is nonetheless not an “intelligible object for our understanding” (A256/B312). As a result the concept of the noumena is only a negative concept “merely thinking [things] under the name of an unknown something” (B312). Again, the capacity for the concept of the noumena to be an object we could know is impossible, because it would imply the representation of an object to the understanding alone, without any sensibility (i.e. not as it appears, but as it is in itself). We cannot cognize an object in this way.


The transcendental dialectic is the “logic of illusion”. Truth and illusion are not in the object, but in the judgment made about the object. Thus error/illusion, are found only in judgments- never in the senses (B350). The focus of this section is not on empirical illusion, but on “transcendental illusion”, or that which “contrary to all the warnings of criticism, carries us away beyond the empirical use of the categories, and holds out to us the semblance of extending the pure understanding” (B352). These are fueled by three principles; immanent, transcendent, and transcendental (A296). This inquiry will be limited to the illusion in transcendental judgments.

This section will “uncover the illusion in transcendental judgments”, as summarized in these points:

·        Logical illusion is only imitation of the form of reason (the illusion of fallacious inferences), and is caused by a failure to observe the logical rule.

·        Transcendental illusion, on the other hand, survives transcendental criticism, and attempts to make assertions about things-in-themselves.

·        Transcendental illusion is unavoidable (as when the astronomer sees the moon as larger than it is, though he knows differently).

·        It is unavoidable because we cannot help but to take subjective principles and pass them off as objective, leading “our reason on with false hopes” (B355).

·        All cognition begins with the senses, “goes from there to the understanding, and ends with reason, beyond which there is nothing higher to be found in us to work on the matter of intuition and bring it under the highest unity of thinking”. (A299)

·        Understanding is the “faculty of unity of appearances”, and reason is the “faculty of the unity of the rules of understanding under principles”. (B359)

·        There is a distinction between that which is immediately cognized and that which we infer.

·        Conclusions from judgments flow through previous judgments. This yields thinking of a “wholly different object”. In this way some rules are obtained which are applied to other objects. In this way (through inference) reason tries to find universal conditions under which to subsume many various cognitions. (B361/A305)

·        Can reason be isolated? If so, then pure reason must have a priori synthetic principles within itself. These principles include:

1)      The unity of reason is not dependent upon sensibility. The unity of reason rather relates directly to the unity of the understanding and its judgments. (A307)

2)      Reason seeks a universal condition for its judgments/conclusions. Better, reason seeks the unconditioned for conditioned cognitions of the understanding.

·        Reason has a synthetic principle, which relates the above (2). This is the “supreme principle of pure reason”, which is transcendent, because it does not rely upon sensibility as does the understanding (whose principles are thereby immanent- reason is transcendent, understanding is immanent). (B365)


Questions for Discussion

·        First, Dr. Neville has corrected me before regarding my misunderstanding of Kant. He tells me that the ‘mirroring’ interpretation of Kant (that our mind mirrors objects) is a misinterpretation, but I still can’t seem to get away from that reading. Dr. Neville, please elaborate.

·        Ideas such as God and the immortality of the soul cannot allow for the application of the categories, which is another way of saying that they are outside of possible experience for us (c.f. A95-97). What is outside experience is unknowable. How then are we reliant upon a priori concepts in order to know only what is valid in experience? This confuses me tremendously.

·        How does Kant speak of an objective time order, if time is a product of the mind’s a priori conceptual apparatus? In other words, Kant maintains that time is a subjective, inner intuition that the mind brings to appearances. Yet he also claims that time yields objective validity. How can this seeming contradiction be resolved?

·        Kant distinguishes pure concepts from those mixed with sensations. But how is it possible for us to juxtapose experience with non-experience. We are never without experience, and experience of non-experience would be an experience, etc. I’m sure that Kant thought of this. But what is the answer?

Again, my most pressing question relates to how Kant can talk about the thing-in-itself, when he insists that we can never know it. How can we say that our intuitions are not what the thing-in-itself is if we cannot know what it is? How can we say anything about that which we cannot say anything about?

[1] Kant hopes to provide philosophy with a “science that determines the possibility of the principles, and the domain of all cognitions a priori” (A3). The understanding is that which provides concepts. Intuition is that which cognizes objects of appearances through the forms of space and time (inner intuition is time, and outer intuition is space). These two are combined in a synthetic way a posteriori, or during experience. In Kant’s second part of the transcendental logic, intuitions and concepts are given a detailed analysis. In short, intuitions are always a posteriori- sensible, and concepts are either a priori pure, or empirical. If pure, concepts have no sensation mixed with them; only the form of thinking an object in general is a pure concept. If empirical, they are intuitions, only possible a posteriori; and sensation is involved. Intuition involves only the way in which we are affected by objects. Understanding, however, is the faculty for thinking of objects of sensible intuition, via the categories.

[2] The categories are only the form of judgment in the understanding, and are divided into four titles, with three subsections (A70-83/B95-116): Quantity of judgments (universal, particular, singular), Quality (affirmative, negative, infinite), Relation (categorical, hypothetical, disjunctive), and Modality (problematic, assertoric, apodictic). The first two categories (quantity and quality) are mathematical, and the second two (relation and modality) are dynamical. These a priori categories are applied to the world (more specifically, to our representations/objects of appearance) via the understanding.

[3] The a priori conditions of a possible experience in general are at the same time conditions of the possibility of the objects of experience. Now I assert that the categories that have just been adduced are nothing other than the conditions of thinking in a possible experience, just as space and time contain the conditions of the intuition for the very same thing. They are therefore also fundamental concepts for thinking objects in general for the appearances, and they therefore have a priori objective validity, which was just what we really wanted to know. (A111, emphasis mine)

[4] If one were to suppose that nothing preceded an occurrence that it must follow in accordance with a rule, then all sequence of perception would be determined solely in apprehension, i.e., merely subjectively, but it would not thereby be objectively determined which of the perceptions must really be the preceding one and which the succeeding one. In this way we would have only a play of representations that would not be related to any object at all, i.e., by means of our perception no appearance would be distinguished from any other as far as the temporal relation is concerned, since the succession in the apprehension is always the same, and there is therefore nothing in the appearance that determines it so that a certain sequence is thereby made necessary as objective. (A194-95/B239-40)

[5] Thus the relation of appearances (as possible perceptions) in accordance with which the existence of that which succeeds (what happens) is determined in time necessarily and in accordance with a rule by something that precedes it, consequently the relation of cause to effect, is the condition of the objective validity of our empirical judgments with regard to the series of perceptions, thus of their empirical truth, and therefore of experience. (A202)

 [6] If one does away with all conditions of sensibility that distinguish [the categories] as concepts of a possible empirical use, and takes them for concepts of things in general (thus of transcendental use), then that is to do nothing more than to regard the logical functions of judgments as the condition of the possibility of things in themselves, without tin the least being able to show whence they could have their application and their object, thus how in pure understanding without sensibility they could have any significance and objective validity. (A242/B300)


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