"I had to deny knowledge in order to make room for faith" (Critique of Pure Reason, B xxx). This remark, taken from the preface to the second version of the Critique of Pure Reason, is one of Kant's most famous. The philosophy of Immanuel Kant (1724-1804) has unparalleled significance for the theology and philosophy of the nineteenth century and beyond. The roles of knowledge and faith are central to that philosophy, a fact that until recently was heavily downplayed by philosophers who investigated epistemology and ethics in ways that ignored theological and historical questions. In this chapter, Kant's philosophy will be presented in two sections in ways that make his theological commitments explicit. The first section will sketch the shape of Kant's thinking, and the second will present some of the technical arguments in relation to what are known technically as his theoretical, practical, and aesthetic philosophy. These divisions will be explained in due course.
Theologians continue to be interested in Kant today because he transforms certain questions inherited from his predecessors, especially those related to clarifying types of investigation, shifting from intuition to discursive reasoning, attempting to offer a "rational" account of respectable habits of thought and action, exploring the character of human freedom, and reconceiving the relation of philosophy to theology. Kant's influence extends far beyond his significance for particular subsequent individual thinkers. His thought has left its mark on the shape of the modern state, not least the university, and the place of religious life and theological reflection within it.
Kant bequeathed a variety of questions to his successors, including those dealing with the scope of modern investigations in metaphysics, epistemology, and ethics. Questions of religious life and theological topics lie at the heart of all of those investigations. He is best known for his "Copernican Revolution" in epistemology, his criticism of arguments for the existence of God, his claim that the concept of "God" is an "idea of reason," and - perhaps most importantly of all - his insistence that persons are autonomous, self-legislating agents who need not and should not rely on the authority of tradition, institutions, and other persons when making judgments. Kant is also credited with or blamed for a number of other inventions, including a division of entities into "noumena" and "phenomena," distinguishing the "thing in itself" from "objects of experience," the claim that consciousness of the "moral law" is a fact of reason, and the development of the notion of "radical evil." These topics will also be explained in what follows. The principal texts in which these ideas are explored, and which Kant wrote in German, are the Critique of Pure Reason (1781, revised 1787), Groundwork of the Metaphysics of Morals (1785), the Critique of Practical Reason (1788), the Critique of Judgement (1790), Religion within the Boundaries of Mere Reason (1793), and the Metaphysics of Morals (1797).
Kant's interest in questions about God was prompted by wide-ranging changes in European society in the eighteenth century. Developments in natural philosophy (today, natural science) had changed the kinds of investigation thinkers employed when describing the world. Rival or novel claims were tested not only in the customary ways - namely, by consulting the great authorities of the tradition -but also by increasingly refined methods for constructing and testing hypotheses. Claims that had been taken as axiomatic began to be taken as hypotheses. These included the claim that the sun rotates around the earth, or that God exists: claims that came to be treated as hypotheses from the sixteenth century onward.
The civil service in Germany had become increasingly important in running the affairs of various princes during and after the Protestant Reformation; it also became increasingly well educated over the course of the eighteenth century. This led to a transformed public sphere in which many questions, hitherto considered inappropriate for public discussion, were hot topics of debate. These topics included the authority of the church, the scope of sovereign power, and the nature of human freedom. These questions became more urgent after the Revolution of 1688 in England, the American Declaration of Independence of 1776, and the French Revolution of 1789. Religious matters were at the heart of these political transformations, and questions of ecclesial authority had themselves become more urgent during the period of reformations from the fourteenth century onward, culminating two hundred years later in the Protestant Reformations in Europe in the sixteenth century. The relatively stable views of natural and social order inherited from classical Greek philosophy were subject to new questions about how best to describe the world. It continued to be taken for granted that there is an analogy between the natural world and the social world, as it had been by the Greeks, but as descriptions of the natural world changed, the nature of that analogy changed too. As debates (about the authority of the Church, for example) grew more intense, questions about how to settle them grew more urgent. What counts as a good argument? How can claims be justified in public debate? What authority does "the public" have? What kinds of investigation are suitable for testing rival claims?
Kant's work focused and drove these debates in Germany for a brief period of perhaps fifteen years, after which rival figures simultaneously claimed the Kantian heritage for themselves and attempted to correct what they saw as its radical shortcomings.
The shape of Kant's thinking is best appreciated by considering eighteenth-century transformations in scientific method and in social life, and the relation of these to each other. Kant inherited well-formed questions about them, above all from Thomas Hobbes (1588-1679), René Descartes (1596-1650), Baruch Spinoza (1632-1677), John Locke (1632-1704), Gottfried Leibniz (16461716), Pierre Bayle (1647-1706), Christian Wolff (1679-1754), George Berkeley (1685-1753), David Hume (1711-1776), Jean-Jacques Rousseau (1712-1778), and Edmund Burke (1729-1797). Among these questions, and the various answers to them, two pairs of oppositions stand out, which Kant inherited and attempted to overcome. The first pitted "rationalism" against "empiricism"; the second opposed "dogmatism" and "skepticism."
Kant rejected, first, both the "rationalism" of Descartes and Leibniz, and the "empiricism" of Locke and Hume. Although there are significant differences between Descartes and Leibniz, they share an assumption that we have innate (but obscure) ideas, and that the task of philosophy is to clarify them. Although there are significant differences between Locke and Hume, they share an assumption that ideas are (obscure) impressions left by objects, and that the task of philosophy is again to clarify them. Instead of treating philosophy as a battle between rationalists and empiricists, as it had been, Kant indicated that two common assumptions generate both rationalist and empiricist approaches: (a) our knowledge is a matter of clarifying our ideas, whether they are innate or acquired - Kant called this shared assumption "empirical idealism," because it implies that what we experience is our ideas; and (b) the conditions for our knowledge - what makes that knowledge possible - are objects in the world, whether reflected in innate ideas, or leaving impressions on our minds. Kant called this shared assumption "transcendental realism." The word "transcendental" here means "the condition under which something is possible." Kant attempted to correct these assumptions, and called his repairs "empirical realism" and "transcendental idealism." Empirical realism names the view that what we experience are objects in the world, rather than our ideas of them. Transcendental idealism names the view that the conditions for our knowledge are our ideas, rather than objects in the world.
Kant rejected, second, both the dogmatism of Leibniz and Wolff and the criticism of Bayle and Hume. This cluster of arguments centers on the scope of enlightenment. "Enlightenment" is a key term in Kant's time. It means different things for different thinkers but has at its core the idea that ordinary people should be able to debate freely, in public, the important issues of the day. Leibniz and Wolff, in Germany, had insisted on a "principle of sufficient reason." This formulation expressed two things. First, there is the claim that everything happens for a reason; second, there is the philosopher's task to defend such a notion of reason against objections. If anything seems to contradict reason, one can presume that in fact it does not, and the philosopher should demonstrate this. Bayle in France and Hume in Britain had insisted that there is no convincing way to prove the reason of everything. Hume had further claimed that people's core beliefs are best described as conventions or habits with particular histories rather than as expressions of an ahistorical reason. The debates here express differing perspectives on order in the world. The rationalists insisted on a prior rational order in the world; the critics denied that such an order could be defended. Kant took both sides to share an important assumption: the task of philosophy is to defend or dispute the discernment of rational order in the world. Kant aimed to correct this assumption by articulating an alternative: the task of philosophy is to defend or dispute claims asserting the rational order of human thinking. Topics such as "cause and effect," for Kant, do not name questions about whether there is cause and effect in the world, but about what it means for persons to attribute cause and effect in their thinking about the world. This is his transcendental idealism.
It can already be seen from these two examples - rationalism/empiricism, and dogmatism/criticism - that Kant attempts to overcome pairs of oppositions. There are many other such pairs, such as materialism/skepticism and mind/ body. In philosophical arguments, once one assumes a split between two things it becomes formidably difficult to avoid unacceptable one-sidedness and almost impossible to show how the two now-separated things are related to each other. Most significant philosophical developments repair the cause of such splits rather than trying to force the split-off elements together, and Kant's philosophy exemplifies this well. He investigates the rule (the habit of thinking) that generates those pairs, and attempts to repair the rule, not merely the claims that characterize the pairs. He turns to transcendental idealism in order to cure the split between innate ideas and acquired ideas, and to cure the split between reason-in-the-world and its denial; this displays a repair of the causes of the split. Kant's distinctive turn is away from the structure of "the world" to the structure of "thinking" (more specifically, of "experience"). He calls this his "Copernican Revolution" because of its analogy with the new cosmology. Copernicus had recast many cosmological problems by a turn to a heliocentric model, where planets revolve around the sun. Kant sees himself as recasting many metaphysical problems by a turn to a transcendental-idealist model, where it is the structure of our thinking rather than the structure of the world that needs investigating. In one way, however, Kant's revolution is significantly anti-Copernican: whereas Copernicus had displaced "us" from the center of the universe (it is now the sun and not our planet that is the center), Kant emphatically placed "us" at the center of knowledge (it is now our thinking and not the world that is the center).
Kant's arguments can be seen as an attempt to save the Enlightenment from self-destruction. The "Enlightenment" names, for Kant, two tendencies in European eighteenth-century intellectual life. The first was to promote the practice of criticism. This meant taking well-established beliefs and examining the evidence for them. It meant converting axioms into hypotheses and constructing tests for them. The second was to widen the scope of explanation. Rather than seeing clusters of phenomena and associating them with relatively independent clusters of categories and modes of investigation, it became common to try to discern the big picture into which all phenomena can be fitted, accompanied by one overarching mode of explanation. This meant showing that particular events or occurrences were expressions of general laws. Kant understood clearly that the practice of criticism threatens to collapse into skepticism, where no claim can be defended against any other. All inferences rest on axioms, and any axiom can in principle be converted into a hypothesis. This pulls the rug from under any absolute objectivity. The practice of explanation likewise threatens to collapse into materialistic determinism, where every event, including all human action, is the product of natural causes. This pulls the rug from under certain conceptions of human freedom. Kant saw that the search for impregnable axioms concerning the world and attempts to defend human freedom in the light of the laws of causation in the world were doomed, at least in their current form. The turn from "world" to "thinking" was an attempt to relocate assumptions: his axioms would be about thinking; his laws would likewise govern thinking. One can see quickly that this solution creates a new separation between terms: this time between "world" and "thinking." Over a century earlier, Descartes had famously appealed to a split between world and thinking, but Kant means something different by it, because he sees all claims about "world" as "thinking" dependent. Yet it is a split all the same, and his successors set themselves the task of identifying and repairing the problematic assumption in Kant's work that causes this split. The philosophical projects of J. G. Fichte and F. D. E. Schleiermacher can fruitfully be viewed as rival forms of repair.
Kant's revolution sets philosophy the task of defending reason and freedom in human thinking. He tends to treat forms of thinking as universal or invariant: as the same at all times and in all places. In contrast to Hume, Kant does not treat either forms of logic (the rules for drawing inferences) or moral maxims (the rules for making ethical judgments) as conventions or habits. Although he addresses the principal philosophical topics as answers to questions about thinking, rather than questions about the world, he reproduces certain rationalist tendencies. Kant treats the structure of thinking, including the structures of moral and creative thinking, as expressions of universal laws. These laws now govern thinking rather than the world, but for Kant they are still universal. He was heavily criticized for this at the time by J. G. Hamann and later again by G. W. F. Hegel. Hamann followed Hume in claiming that patterns of thinking, just as much as discernible patterns in the world, express habits with histories. Hegel developed this further in describing concepts as products of social action, thus reintroduc-ing the dimension of social life that appears almost absent in Kant.
Kant's ahistorical universalism shows itself in his "theoretical" and his "practical" philosophy, and in his remarks about nature, art, the beautiful, and the sublime. The "theoretical philosophy" generally refers to his recasting of debates about the soul, the world, and God along transcendental-idealist (and thus empirical-realistic) lines. The "practical philosophy" refers to his recasting of debates about human freedom and divine action in the light of consciousness of "the moral law." In both contexts, Kant ascribes necessity and universality to what Hume called conventions or habits. In his theoretical philosophy, Kant describes concepts as "rules for judgement," and claims that the "categories" governing such rules are invariant. By "categories," Kant means the building blocks of formal logic. In the practical philosophy, Kant describes freedom as people's capacity to legislate their actions for themselves in a reasonable manner, in accordance with "the moral law." He claims that consciousness of the moral law is a universal "fact of reason." He also claims that the most basic maxim of all, the "categorical imperative," applies to all persons at all times in all places. Even more radically, he considers many of the most important moral conventions of his time (especially the practice of telling the truth) to be binding in a way that is universal and invariant.
Along with a strong universalism, Kant displays an emphatic individualism. The practice of judgment that lies at the heart of his epistemology has at its core the spontaneity of the irreplaceably individual human subject. At the heart of his moral theory lies the irreplaceably individual responsibility of the human subject. The human subject thinks for itself and is responsible by itself. Institutions, languages, communities, and conventions are all merely shells in which individual agency is contained. Kant has no significant account of institutional agency, linguistically shared horizons, or communal responsibility. Unsurprisingly, his account of the relation of divine and human action - in a word, his understanding of "grace" - has no reference to sacramentality, cooperation, participation, or life of the Spirit, but is merely "something incomprehensible." His verdict is that we "cannot incorporate it into our maxims for either theoretical or practical use" (Religion 6:53). Put plainly, in the light of the categories he uses and the way he uses them, the role of grace in Kant's philosophy is almost unrecognizably different from its role in theology in the previous centuries.
Kant's work can thus be understood in terms of three significant presuppositions: (a) appeals to habit do not constitute good reasons for action; (b) individual agents are solely responsible for their free actions (including what they think); and (c) in order to make sense of events in the world, we must treat human action as both naturally caused and freely willed. Taken together, these three presuppositions require a rethinking of forms of argument that rest on memory, history, or habit; of accounts that stress the corporate, social, and historical contexts of meaning and responsibility; and of explanations which insist one-sidedly either on human freedom or on efficient causality as the basis for human action. Kant inherits many habitual practices like care for the vulnerable, imprisonment of criminals, and praise of the virtuous. He sets himself the task of showing how these practices are rational and can thus be justified independently of appeals to history or trust in institutions. The juxtaposition of the new scientific habits of investigation with older habits of consulting eminent authorities, both of which intend to discover the "truth" about the world, leads to contradictions and confrontations of various kinds. Kant sees it as his vocation to adjudicate some of these by adopting an ahistorical perspective.
There are important theological implications which relate to the historical context in which Kant was writing. Prior approaches were generally associated not just with an easily legible cosmic order, but also with an easily legible divine order. God orders the world and God makes it legible to us. This meant that there were many available forms of investigation into the order of things, including looking at things in the world, looking at Scripture, and looking at Church doctrine. Renaissance thinkers a few generations before Kant had often talked of the "book of nature" and the "book of Scripture," for example. The most widely respected views of order were those that most successfully harmonized investigations into things in the world, Scripture, and Church doctrine. Copernicus himself made no strenuous efforts to harmonize them, and his views in De revo-lutionibus orbium coelestium (1543) were thus treated as not merely unrespecta-ble but also heretical. A century later, one sees increasing extremes. Spinoza's Tractatus Theologico-Politicus (1670) argued for a separation between what scripture teaches and what can be learned from philosophy. By contrast, Locke's The Reasonableness of Christianity (1695) constitutes a well-known English attempt at harmonization between "reason" and "scripture."
In What Is Enlightenment? Kant insists that rationality is properly ascribed to the individual thinker rather than to institutions. Thinking is something one must do for oneself rather than learn from or accept from anyone else. The key words here are "rather than." Kant does not merely recognize the difference between the irreducibly individual quality of judgment and the unmistakably shared quality of institutional action: he sees them as mutually opposed. This is noticeably unlike Joseph Butler in the generation before Kant, whose Analogy of Religion (1736) insists on the irreducibly individual quality of judgment and the genuine possibility of shared action and responsibility. It is also unlike Friedrich Schleiermacher in the generation after Kant, whose Hermeneutics and Criticism (c. 1828) likewise insists on the shared quality of rule-systems and language and on the individual quality of judgments within them. These two theologians insist on both individual and institutional dimensions in relation to each other. Kant separates them, in a binary opposition, and then associates institutional control of action and thinking with "theology" and individual responsibility and thinking with (his) "philosophy." Naturally, his own philosophy is deeply theological, in the sense we normally use that word.
Many of Kant's subsequent interpreters do the same. Theologians should thus expect to read accounts of Kant which claim simply that he broke with the theological approaches of his predecessors. Of the many strands associated with this word "theological" as used by Kant's interpreters, we can discern three. They are related to each other. "Theological" refers, first, to the idea that divine order is readily legible; second, to the enforced demand that there be harmony between the outcomes of investigations into things in the world and into scripture and doctrine; and, third, to the subordination of individual judgment to institutional control. Although it is possible in theology to offer subtle accounts of legibility, to distinguish different forms of inquiry, or to account for the relation between individual and institutional action, philosophically informed accounts of Kant's intellectual context often do not reflect this.
The word "reason" evidently plays a central role in these discussions. It is worth thinking historically about the term and its scope. The Peace of Westphalia in 1648 had established what one might call "minimal rules" for governing relations between religious communities. The failure of political and religious leaders to support the Peace of Augsburg of 1555 had led to the Thirty Years War. The minimal rules articulated at its end included the two famous principles that the ruler of a kingdom would determine the religion of his state (whether Catholic, Lutheran, or Calvinist), and that minority denominations in those states would be free to worship publicly without harassment. The major thinkers of the period after the Peace of Westphalia - Descartes, Spinoza, Locke, and Leibniz - set themselves the task of formulating these minimal rules more precisely. They sought to discern how members of different traditions could all adopt a common set of rules for public argumentation, for formulating and testing hypotheses, and for interpreting Scripture.
At first, these rules presupposed the continuation of distinct traditions. These distinct traditions would continue to have their local customs, their particular practices, their distinctive theologies, and their styles of worship. But they would be able to live together, in the same cities, in peace, because their relations with each other would be governed by a set of minimal rules. These minimal rules were a response to widespread suffering: entire economies had been bankrupted and entire regions had been destroyed by desperate armies. Many of those who had survived armed assault were now picked off by the famine and disease caused by the economic and agricultural collapse.
The philosophers mentioned above were, however, not satisfied with minimal rules governing different traditions. These minimal rules were what eventually came to be called "reason." The philosophers expanded their scope and extended their reach into all areas of life, including theology. When Denis Diderot and Jean le Rond d'Alembert published their Encyclopédie in the 1750s, they explicitly intended to organize all knowledge according to these now far-from-minimal rules. The Encyclopédie famously includes a telling line, "Reason is to the philosopher what grace is to the Christian." It is the contrast between these terms that is significant here. For previous theologians, it was obvious that reason and grace were harmoniously bound up with each other. Now they seem to be competitors.
Kant's Religion within the Boundaries of Mere Reason (1793) consummated this trend in a most intense fashion: he offered a complete view of religion, rendered in terms of these rules. What had started as "minimal rules" formulated for the sake of peaceful relations between communities had become "maximal reason" which permitted universal claims about everything. What had been conceived to regulate external interactions between communities were now extended to regulate meanings internal to those communities. Whereas the sphere of public interaction (including reasoning about institutions in which more than one tradition played a part) had been governed by minimal rules, there was now an established project to have the public sphere governed by maximal reason. Scripture was now subservient to these rules, in a quite comprehensive fashion. Instead of being rules whose purpose was restricted to governing the relations between traditions with decisive theological differences, they become - for Kant - rules for governing theological topics themselves, insofar as theological claims can be justified publicly. When Kant appeals to "reason," he means this in a maximal sense.
In summary, before considering the technical details of Kant's project with an eye on its theological details and implications, we may say that Kant attempts to repair problems he discerns in all his predecessors. He rejects the one-sidedness of rationalism and empiricism and attempts to mitigate the dangers of radical dogmatism and skepticism. He does so in ways that integrate recent insights in natural philosophy and recent trends that question the authority (and indeed agency) of institutions. His model of the human subject is of an individual agent, whose individual thinking is the principal condition for its individual action and of any explanation of that action. In other words, religion will turn out to be a distinctly private and individual matter for Kant.
Was this article helpful?