The medieval harmony between philosophy and religion, natural and sacred theology, reason and revelation, has undergone two heavy attacks in modern times which have radically disrupted it. The first attack was made from the side of religion, the second from the side of philosophy. Luther and Kant were the initiators respectively. They had the same target, they rejected purely intellectual or theoretical knowledge in the field of theology; or, in other words, they denied the validity of Greek thought in this field.1 Their arguments and even their motives were different, and so also the results they accomplished. Luther fought against human reason in general so far as it was not supported and inspired by the word of God. Kant strove against the primacy of theoretical speculation in the whole fabric of human valuations and propagated, instead, the primacy of practical or ethical reason. The interest of Luther was dictated by his belief in the activity of God alone; the interest of Kant by his critique of pure reason. An immense gap separates these outlooks, the gap between two different ages. Luther was rooted in medieval ground, Kant was spokesman for the modern spirit. But this modern day begins already to decline. We no longer believe so much in man as did the contemporaries of Kant. We begin to realize again that faith in the power of God is the basis even of man's own power and of reason's achievements. Therefore we must stress once more the religious outlook, without cancelling the benefits bequeathed by Kant. We must attain a new harmony between religion and philosophy. This task cannot be achieved by going back to any former position, be it that of Thomas Aquinas or Augustine. We must not forfeit the advantages of Kant's Critique.

It is an astonishing paradox in the history of the European mind that it was the Christian Church which propagated the ancient or pagan philosophy by resuming, first, Platonic and Neoplatonic schemes of thought, and then renewing the Aristotelian philosophy, while the succeeding modern epoch, which was in so many respects more pagan than Christian, rejected the ancient forms of thought and created, step by step, a philosophy that was born out of the Christian conscience as rediscovered in Protestantism. This new philosophic movement reached its summit and found its maturest interpreter in Kant. The key to the understanding of this paradox is the fact that Greek, and especially Aristotelian, thought, though theological, nevertheless is not originally Christian, while modern, and especially Kantian, thought, though not theological, nevertheless is essentially Christian.

It was protestant piety which abandoned the patterns of ancient philosophy and discovered a new method of thought. The protestant faith protested not only against catholic faith but also against catholic theology and philosophy. The protest against catholic philosophy reached its consummation in Kant's critique of natural theology, for this theology was an integral part of scholasticism. Scholasticism asserted the possibility of rational knowledge of God in agreement with the Christian faith. It followed the dictum of Augustine: “Si sapientia Deus est, per quem facta sunt omnia, sicut divina auctoritas veritasque monstravit, verus philosophus est amator Dei.” By applying the ancient conceptions concerning the relation between God and the world, scholasticism tried to base theological speculation on “pure reason” and on the Christian faith as well. Kant demonstrated that pure reason is incapable of producing such theological knowledge. Kant's Critique of Pure Reason is at the same time a critique of European philosophy as developed from the Greeks to Leibniz; it is the critique of Greek reason.

What is the peculiar character of Greek thought, as criticized by Kant? It is not so much a body of doctrine as an attitude. This attitude originated in the assumption that not religion but philosophy opened the path to the knowledge of God. Lacking a true religious knowledge of God, the Greek was driven to build up a philosophic knowledge of God that was superior to his religious imagination. Thus the consciousness grew and was finally proclaimed by Aristotle that thought or pure reason can accomplish what religion cannot, and can attain to an adequate idea of God, to a theological metaphysics. In that way the primacy of philosophic speculation over the religious life was established. Not faith but reason first established the monotheistic idea of God and thus deepened the religious consciousness. It was philosophy which raised the idea of God to an ethical level not reached in the popular myths.

This situation was wholly altered during the Christian era. No longer was philosophical thought deemed the superior faculty. Not scientific knowledge, but the actuality of religious life had reached the higher level. Philosophy was outdone by revelation, the thinker by the prophet, Socrates was surpassed by Jesus Christ. The Christian ethic superseded the ethic of paganism, even in its purest and highest manifestations. Religious sects, descended from philosophical systems or cults, were overpowered by the growing Christian community. It was not until Kant that the implications of this situation were realized in the realm of philosophic study. He was the first to understand by purely philosophic means why Christian faith had been able to triumph over Greek philosophy, by showing the limit of pure reason in the realm of speculative theology. He defeated speculation in its own stronghold and by its own methods: it is pure reason that criticises pure reason in Kant's Critique.

Although philosophy was called the handmaiden of theology throughout the Middle Ages, the real relation between speculative philosophy and Christian theology during those centuries is not accurately described by that statement; for though it is true that theology was the master in the house of scholastic philosophy, this theology itself was mastered by speculation and by categories derived from Greek thought.2 Aristotle and not the Gospel was victorious in scholasticism. The philosophic development from Augustine to Thomas exhibits the ever-increasing adoption of thought elements originally and essentially foreign to the Christian faith, the growing self-estrangement of the basic attitude of prophetic religion. It marks a period of an ever-advancing secularization of theological thought. Luther, therefore, opposed scholasticism as he opposed the whole tendency of that development. And Kant finally gave philosophy a new foundation with faith as its basis.

To be sure, Kant's accomplishment should be qualified, because his criticism of rational theology did not immediately serve the Christian faith but instead a rational faith based on practical (moral) reason. And in this respect Kant's philosophic standpoint is more remote from the Christian faith than the scholastic system had been in spite of the latter's Aristotelian foundation. Confusing and interwoven are the historical motives and trends in the development of European thought. A real Christian philosophy, therefore, has not yet been written. One must agree perfectly with Karl Barth when he says, that all endeavor to create a Christian philosophy has failed so far, and that the thinkers who aimed at such a philosophy produced “either a real and then no Christian or else a Christian and then no real philosophy.”3

Kant's “critique of all theology, based upon speculative principles” intended to destroy forever all purely rational knowledge of God. Kant shows that no extension of the categories which make experience, and therefore science, in the empirical world possible, can be permitted in order to attain knowledge of things beyond that world. We are able to explore causal relation in the world of sense, because our intellect connects the sense data according to the rule of temporal sequence. But in the field of the supernatural, or the divine, no sense data are at our disposal and, therefore, no use of the rational rules or forms of connection is possible. Thus no rational knowledge of God, no natural theology can be achieved. If we try to attain knowledge of God by rational means, then we ensnare ourselves in mere illusions. Kant expressed this doctrine in an extremely sceptical fashion; he vehemently denied the right and the ability of reason to attain to any legitimate knowledge of God.

Kant derives the idea of God from the imperfection of all empirical knowledge. No empirical object can ever be perfectly known because we have no adequate intuition of the sum total of all material conditions which determine the reality of any entity in the empirical world. Our empirical knowledge is always fragmentary and can never be complete. Even the idea of an end of our knowledge is hypothetical because the very nature of infinity contradicts the possibility of such an end. Nevertheless our reason is bound to conceive of the absolute perfection of our knowledge as the practical goal of all our scientific striving. We need the idea of the end of our striving as an ideal of reason. Kant calls this ideal “transcendental” because it transcends the horizon of the empirical world, and of empirical knowledge altogether.

The transcendental ideal represents a problem never to be solved by knowledge. It contains the positive determinations of all things real and possible, therefore it has rightly been called the “ens realissimum,” i.e., the most real thing. If we hypostatise and personify this ideal, it takes the shape of a highest being or of the being of all beings, in other words, of God. But this hypostasis and personification is in no way justified by reason. “In any such use of the transcendental idea we should, moreover, be overstepping the limits of its purpose and validity. For reason, in employing it as a basis for the complete determination of things, has used it only as the concept of all reality, without requiring that all this reality be objectively given and that it be itself an existing thing. Such a thing is a mere fiction in which we combine and realise the manifold of our idea in an ideal, as an individual being. But we have no right to do this, nor even to assume the possibility of such an hypothesis. Nor do any of the the consequences which flow from such an ideal have any bearing upon the complete determination of things, or exercise in that regard the least influence.\…”4

In accordance with this sceptical attitude Kant denies the validity of any proof of the existence of God by theoretical means, or by means of speculation. All these proofs are completely illusory, as Kant shows in detail. Even if we were rightly entitled to grasp the idea of God in the way mentioned, we are not allowed to assert the existence of the object of this idea. To assert that an individual being exists, demands the real or possible experience of this being, the possibility of its appearance, and we have no means of assuring such a possibility; on the contrary, it is excluded through the very nature of the idea or concept of this being. Reason alone, moreover, unsupported by intuition, cannot deduce the existence of anything, for existence is no rational predicate at all; it is a predicate that demands the context of a possible experience to be attributed to an idea or to its object. The transcendental ideal is an ideal only, it is no real thing; this is as much as theoretical or speculative knowledge can affirm.

Kant's verdict against all speculative theology is relentless. “Our understanding is in no way fitted” for it.5 Kant discloses the abysmal depth of human ignorance in this field of knowledge.v There is a boundary line between our mental faculty of understanding on the one hand, and religion, on the other hand, between reason and faith. Reason can never transcend this line. Kant criticises reason, as he says in the preface to the second edition, “in order to make room for faith.” His scepticism in no way extends to religion, it concerns our human knowledge only. It is a scepticism directed against theorizing about God, by no means against our belief in the existence of God. Kant sharply separates theoretical knowledge and religious belief. Belief is, as Kant's doctrine of rational faith defines it, the attitude of practical or moral, not the attitude of theoretical or speculative, reason. To save and to defend faith against all possible scepticism, Kant smashes all arrogant knowledge in the field which sensation and perception can never reach.

“Pure” reason is purely negative. It can criticise itself but it cannot produce any real knowledge. The religious source of Kant's attitude is Protestantism. Luther's doctrine that faith, and faith alone, can constitute man's relationship to God has found an adequate philosophic ally and its expression in Kant's Critique. While medieval Catholicism had brought about a system in which nature and grace, world and God, reason and revelation, were integral parts, supplementing each other, so that the whole was in perfect equilibrium in spite of the gap between the parts, Protestantism stressed the fact of the gap. While the catholic system reconciled the oppositions by means of a hierarchy which mediated between the lowest and the highest spheres in accordance with the neoplatonic type of philosophy, Protestantism emphasized the mission of God's word and of Christ as the only mediator between God and man, and thus generated the Kantian type of philosophy.

Protestantism rediscovered the paradoxical character of the Christian creed, and opposed it to the orthodox character of the scholastic system. The fact was emphasized anew, that the Gospel is called a stumbling block and foolishness. Instead of the rational reconcilation between revelation and speculation effected by Thomism, Protestantism restated the impossibility of reconciling reason with the nature of God's mystery.6 In Kant's Transcendental Dialectic this new (and old) religious outlook is reflected. Unavoidable antinomies, natural paralogisms, fatal illusions bar the way to the throne of the Highest for human understanding. Reason must capitulate to faith. Christian dialectic, as it appears in the parables of Jesus or in utterances of Paul, has not only the same implication as Kant's dialectic, but is also akin to it in spirit. Both point to the divine mystery which cannot be revealed without contradiction, and which therefore transcends the rational sphere.

Of course there is an important difference between the paradox of faith and the anti-dogmatic content of Kant's philosophy. Both agree in restricting human understanding, but while faith uses the paradox to express a truth that transcends its limits, Kant uses criticism to a purely negative end, at least for the possibility of human knowledge. There is no “dialectical method” whereby positive truth may be discovered. Kant does not exalt the “law of contradiction” in order to express truth as Hegel does. Kant does not establish a philosophic “paradox.” On the contrary, he believes that he can explain why human understanding necessarily comes to contradictions, and in what way the contradictions are to be solved, namely, by restriction of our knowledge.

Is Kant's verdict a final one? Has his Critique annihilated speculative theology for all time? Docs his negative attitude bind us still? Is no reconciliation possible between speculation and faith? Is it true, that all natural theology, from Aristotle to Hegel, from Clement to Thomas, was based on logical fallacies? Is the gap between reason and faith as deep and abrupt as Kant asserts? These questions we must discuss in order to reconstitute natural theology on a new basis.

Two items must be taken into consideration for this purpose. First, the relationship between theoretical (or speculative) and moral (or practical) reason and knowledge; second, the concept of existence as used by Kant with regard to the transcendental ideal, and rejected by him. The first item cannot be considered in full until Kant's doctrine of the primacy of practical reason and of rational faith has been developed in the next lecture. One point, however, may be mentioned here. The complete separation of mental faculties or of different phases of human reason is, though old in substance, more emphasized and developed by Kant than ever before. Of course, the division of problems into theoretical and practical has been classical since Aristotle. But Aristotle's metaphysics is far from being purely theoretical in the sense of Kant. On the contrary, Aristotle's doctrine concerning the existence and the nature of God combines precisely the functions of both theoretical and practical reason, or the viewpoints of logic, physics, and ethics. God is not only pure speculative reason; as the prime mover of the world, he is also the highest good. It is true, God's actuality is, according to Aristotle, the actuality not of the will, but of thought, and he is good in the highest degree, because he is this actuality in the highest degree. “It is through thinking that its value belongs to it.”7 On the other hand, “God thinks of that which is most divine and precious.” The highest good which is represented by this actuality is the theoretical and moral order of the world, or the world's unity. In this respect he is the mover of both nature and the moral world, without being moved, as the object of desire and of thought; as this object he is desired not arbitrarily, but because he is “in itself desirable,” and accordingly the best in every regard.8

It is difficult if not impossible to compare Kant with Aristotle without analyzing all the terms which both use, and it cannot be the task of this lecture to engage in such an analysis. But it can be maintained that Aristotle is far from thinking of God in the fashion criticised by Kant. The concept of God as designed by Aristotle is not the concept of all reality hypostatised and personified in an individual being; it is rather the concept of the thinking mind, freed from all restrictions which characterise the human mind. It is not the concept of a thing that is personified; it is that of a person who is nothing but a thinking mind. Aristotle emphasizes the actuality or the act of thought, in which God thinks the unchangeable, immovable, eternal truth, the full truth, all truth. God is this truth, he is what he thinks, and he thinks what he is. Truth is thus the actuality of thought. It is not really a thing, it is life, as Aristotle says. These determinations are not contained in Kant's concept of the transcendental ideal. Kant is not reflecting on the act and activity of thought when he criticises the speculative theology of the ens realissimum, or of all reality as itself an individual thing. Pure reason as criticised by Kant is thus a special type of reason, but not reason unqualified.

This deficiency in Kant's treatment of speculative theology is connected with the second problem that should be taken into consideration, namely with the concept of existence as a predicate of the ens realissimum. Kant is surely right in insisting on the impossibility of positing the existence of an individual being by means of thought only. But he goes too far when he deals with the transcendental ideal as an ideal of human reason only, as if no kind of objective reality could be attributed to it. It may be true that we have no objective intuition to fill the idea of the ens realissimum, and that even this idea in itself, i.e., its connotation, is questionable; nevertheless it cannot be denied or doubted that something must needs correspond to this problematic idea, something that not only belongs to the human mind or reason, but to the nature of being itself. The necessity which forces upon us the idea of the highest being is not a psychological one, it is a logical or ontological necessity. We may not know anything about the nature of the object of this idea, nay, we may even be obliged to admit that the content of the idea is “hypothetical” or problematic, nevertheless the idea is objectively necessary, for we know that truth about empirical objects cannot be fully obtained without that determination which is assumed to be contained in the object of this idea.

In other and simpler words: if it is not true that something exists which corresponds to the object of the problematic idea, then nothing at all can exist. If we call this something “God,” then we can conclude that the existence of “God” is the necessary condition of the existence of everything that exists. Reason must appeal to “God” as the highest instance of all knowledge, simply because the name of God represents the highest goal of all knowledge: the goal of truth. The idea of truth is the point where epistemological and ontological thought converge and mingle.

To be sure, if we reserve the concept “existence” to individual things and beings only, then we must admit that reason cannot grant the existence of God as the object of the transcendental idea. God cannot be thought of as an individual. But is this impossibility a lack of insight on the part of reason or thought? Is it not, on the contrary, a real insight that God is not to be known as an object of experience; that He is not on the same level as a stone, a plant or an animal, not even at the level of the heavenly bodies which Aristotle and even Origen put in His vicinity? If Kant had denied the existence of God in this restricted sense only, then he would obviously have been right. But he was not right in regarding the impossibility of thinking of God in this fashion as a deficiency of reason. It is not a deficiency of the human mind that it cannot perceive God like other empirical things, for God does not belong to that order.

Is Kant then right in saying that there is no objective, theoretical knowledge of God at all? He would be right, if he confined the meaning of objective, theoretical knowledge to the scientific realm alone. Such a determination would not exclude a knowledge of God which, though not objective, nevertheless would be theoretical in the same sense in which the Critique itself is theoretical. The Critique does not contain objective scientific knowledge or knowledge of the objective world, but rather knowledge of knowledge or self-knowledge of knowledge. Is not perhaps the knowledge of God, if there be such, akin to this self-knowledge? If that should prove correct, then it would follow that Kant had not destroyed speculative theology altogether. He destroyed a special kind of rational theology, the kind which dealt with God in the same way as science deals with matter and natural powers, as if God were a thing like other things in space and time. He destroyed that kind of theology which proceeded by analogy with the natural sciences. And thus he destroyed the natural theology founded by Aristotle and maintained by all his followers. For Aristotle, although he recognized God as a thinking spirit, nevertheless determined the concept of the divine, not by means of self-reflection, but instead by means of objective knowledge and inference: God is the prime mover of the world, He is a thing like all other things, belonging to the same world of objects as natural things, though possessed of a special essence. All successors of Aristotle in the Middle Ages held to this standpoint in principle; Leibniz, indeed, was still following his model. Kant was the first to expose the radical failure of all these attempts.

At the same time it must be remarked that neither Aristotle nor his successors and followers were so blind as not to see the difference between God and finite things in the world. They saw this difference but they did not succeed in clarifying it sufficiently. In spite of this insufficiency some insights gained by them are not to be neglected, and Kant was surely wrong in annihilating all speculative theology because of that mistake which he rightly discovered. He was wrong in identifying all possible speculative theology with the type of a science of God which he criticised because it was built up by analogy with the natural sciences. Kant was able to separate physics and metaphysics radically because he discovered the peculiar co-operation of sensation and intellect in the realm of the natural sciences.

Aristotle was “speculative” even in the field of physics as he was “empirical” in the field of metaphysics. He did not fully realize the gap between philosophic and empirical, metaphysical and physical knowledge. It is characteristic that his metaphysics contains a theory of the physical universe regarding the solar system, while his physics deals with the metaphysical problem of space and time. His metaphysics is as physical as his physics is metaphysical, if we use the terms in the modern fashion. Kant, on the other hand, was so eager to analyze scientific knowledge that the very concept of knowledge blended with the special kind required by science. Consequently he felt obliged to deny the legitimacy of all rational knowledge of God altogether, not acknowledging that speculative theology at all times was more, or was something else than merely a branch of science in the sense inquired into by the Critique of Pure Reason.

Now a most serious and grave question arises: is any other speculative theology possible if reason avoids the way in which Aristotle and all his followers have proceeded? Is it possible to retain the Aristotelian type of theology after having purified and purged it of those elements which can no longer be retained? The mere reference to the knowledge validated by Kant's Critique itself (to the reflective knowledge of knowledge) cannot suffice. This knowledge, though surely not scientific (that is, not empirical in the sense of the natural sciences), is not speculative (that is, not metaphysical in the Aristotelian sense of theology) either. It has human knowledge as its subject matter, not God. It is a metaphysic of knowledge or an epistemology and not a metaphysic of being or an ontology. Is it possible to graft this kind of epistemological knowledge upon the subject matter of theology? Is there any inner connection between the activity of our own understanding and the concept of God? Is there any access to God through knowledge from the standpoint of epistemological self-knowledge?

At first sight it seems as if this question should be answered in the negative. What a difference between our own way of acquiring knowledge concerning the objects as they appear in space and time, i.e., our empirical knowledge as analyzed and justified by the Critique, and—God as we know Him in the Bible! How is it possible to construct a bridge over this chasm? Is it possible at all? The activity of our own understanding in building up empirical knowledge can be experienced in a certain way. It is, though no empirical object (in the sense of the natural sciences), nevertheless an object of reflective experience, moreover of an experience which is concerned indirectly with empirical objects. God, on the contrary, does not belong to the realm of this inner experience. Should Aristotle's determination of God as “thought of thought” prove true, even then a speculative theology based on the self-reflection of the human understanding is not possible. The human self and the self of God cannot be inquired into by means of the same method. There is no possible reflection on the self of God from the standpoint of man. Even if it were true that the nature of God is, as Aristotle asserts, an everlasting activity of self-knowledge, this self-knowledge could never become our own self-knowledge!

If there were, on the other hand, no connection between our empirical knowledge and the idea of God, then Kant would never have spoken at all of this matter in his metaphysic of knowledge. He would never have criticised speculative theology, if a close connection did not exist between our empirical cognition and the idea of God. Indeed, there exists such a coherence between them. The transcendental ideal as introduced by Kant means nothing but the ideal of all empirical cognition; it means the idea of an absolute completion and perfection of knowledge, or the ideal of perfect truth. Kant rejects the knowledge of God on the ground that this ideal can never be achieved by means of objective knowledge. He is right in this respect. But he forgets that the ideal of perfect truth transcends the limit of objective knowledge in any case, that it is not the limit of the human mind which forbids an objective knowledge of God but rather the nature of God who is no object and cannot become the object even of the most perfect objective knowledge! Kant does not realize that the ideal of an absolute completion of all empirical (scientific) knowledge leads beyond the entire sphere of all empirical objects; or in other words, that this ideal concerns not so much the completion of all empirical knowledge alone but the completion of the metaphysic of knowledge (of self-reflection or self-knowledge) as well. He forgets that, if there is any knowledge of God at all, this knowledge must be constructed by analogy with self-reflection, since God is no object but a self. Kant was misled by the fact that all speculative theology before his time had been constructed as an objective knowledge, that is, as the knowledge of an object, though of the highest and perfect object; of a thing, though of the most real thing.

There is still another reason why the belief in the possibility of an objective knowledge of God had been maintained so long before Kant, and why even Kant himself did not envisage any other possibility: the existence of a kind of experience of God which is, though different from, nevertheless akin to, our empirical experience of nature. I refer to religious experience. Aristotle could believe that it is possible to transform religious knowledge into metaphysical thought in exactly the same manner and with the same success as it is possible to transform our empirical knowledge of sense objects into scientific (physical and metaphysical) knowledge. Since religious knowledge, as familiar to him, was mythological and therefore seemed to be as undeveloped and childish as crude sensation, he could think that both sense perception and mythological imagination could be purified by thought. Both were tainted with imaginary elements, and had to be revised and purified by reason. Aristotle substituted his critical metaphysical theology for the naive faith of the Greeks. He did not notice the chasm between faith and knowledge. Or in so far as he noticed it he was naturally and rightly led to the conclusion that metaphysical knowledge was superior to mythological imagination. The Christian metaphysicians, from Clement to Thomas, knew the difference between faith and knowledge, and they also knew the supremacy of revelation and of revealed knowledge. But they, like Aristotle, believed uncritically in the possibility of a natural theology, and they held that both natural and revealed theology could form one great whole. They did not reflect on the rupture between reason and revelation, although they restricted the power of understanding the content of faith by means of thought. But the important point is that they assumed the possibility of a conceptual knowledge of the living God; they did not recognize that this knowledge necessarily and essentially is imaginative and must remain imaginative. Clement, the first in the long series of Christian thinkers, calls the highest stage of faith gnosis and he is convinced that gnosis is the only true philosophy. All his successors shared this opinion in a certain measure. All of them believed, therefore, not in the primacy of faith qua faith, but in the primacy of faith qua knowledge of God, and this knowledge was religious as well as philosophic, revealed as well as natural, that is, rational.

Kant, on the other hand, wanted to restrict knowledge to “make room for faith.” Thus he tried to destroy natural theology forever. And he was possessed of the conviction that all knowledge of God is illusory. He failed therefore to recognize the deep chasm between the empirical knowledge of nature, which he deemed valid, and the rational knowledge of God which he held illegitimate. The train of his argumentation can be rendered in the following syllogism:

God is the Supreme Being.

The knowledge of real beings requires empirical perception.

There is no empirical perception of the Supreme Being.

No knowledge of God is possible.

This syllogism is quite correct. But Kant is blind to the fact that the knowledge denied by this syllogism would be an empirical knowledge of God, and that such an empirical knowledge—if we exclude religious experience and revealed knowledge—is not even to be desired! Kant does not see that the reason why an empirical knowledge of God is denied to man should not be sought in man's restraint, that is, in the restriction of his finite intellect, but rather in the nature of the Infinite Spirit. Not man alone, but no intellect whatsoever can know God or should want to know God empirically, because God by His very nature is not an empirical object, but the ens realissimum, the Ideal of Reason, the supreme Self. In other words: not man's intellect, not the finite intellect, but rather intellect qua intellect cannot know the living God.

Should knowledge of God be possible in theoretical science, this science would have to be super-empirical or, as Kant uses the term, speculative. God cannot be regarded as just another kind of object; He is rather the Supreme Being because He is no object at all, but instead the highest, the perfect subject: Infinite Spirit. This truth is not achieved in the Critique of Pure Reason, although it is its necessary conclusion. In his later works, especially in the Critique of Judgement, Kant worked his way to it. There he conceived of the divine intellect as the perfect intellect which is no longer separated from intuition and therefore no intellect at all in the human sense. Rather it is a creative spirit. The restrictions of the human intellect, Kant then stated, do not consist in the lack of an empirical intuition or perception of the Supreme Being, but in the lack of intellectual, super-empirical intuition. The divine spirit is now characterized as possessing a productive intuition in himself, or as producing knowledge out of his own creativity without requiring support from sensation or from corresponding superhuman perception. Man would understand the divine spirit only if he could produce the knowledge of God in the same way.

Kant thus approves of a certain philosophical knowledge of God. Indeed, he corroborates and even augments the first entirely repudiated and refuted natural theology at the end of his career! He elevates the idea of God over the level of an ens realissimum, of an all-embracing object, of a thing-in-itself; he acknowledges that this highest ideal of reason is nothing short of the perfect knowing subject, the ideal self of knowledge. He realizes, in other words, that natural theology corresponds not to empirical science, but to reflection on empirical science and on the knowing subject. God must be conceived, not as an object that we cannot perceive, but as a self that we cannot actualize in ourselves because it transcends the limit of human subjectivity and the conditions of human activity. The knowledge of God is no knowledge of an object, it is God's knowledge of Himself so that He Himself is the only norm and the very archetype of truth. This idea reapproaches the concept of the Aristotelian god. His successors were encouraged by this idea to venture a new revival of metaphysics on the basis prepared by the criticism of Kant.

I should like to draw some conclusions important for the discussions I will pursue in these lectures. God, in so far as pure reason can attain to a knowledge of Him, is not an object, not even the sum total of all objects; He is rather the all-embracing subject or the ideal self. But He is not only the self of perfect knowledge, He is also the perfect will; He is creative in both respects, and therefore no longer a knowing intellect or an acting will in the human sense. But we do not know of any other intellect or will by experience, and therefore the idea of the divine intellect and the divine will remains problematic; it remains the content of a problem, the solution of which is denied to us. Natural theology is the science of this problematic idea. Though the idea is problematic, it is nonetheless of the greatest importance, since it closes the system of thought not by giving final answers but by showing the necessity of revelation. Faith supplements what is lacking in the field of reason. Revelation delivers what experience lacks, not in the form of another empirical datum as the theological empiricists would claim (thus destroying the fruit of Kant's criticism), but instead in the form of an experience that is appropriate to the mystical nature of the Ultimate.

Kant did not succeed in appraising the true function of the religiously inspired imagination or prophetic consciousness because he was and remained throughout his life a child of the age of reason. He never overcame the prejudices of this age in spite of his discovery of the limit of reason, and in spite of his program to deny knowledge in order to make room for faith. He persisted on the one hand, in the rejection of all natural theology but, on the other hand, he did not attain to a just appreciation of faith and revelation, of inspiration and imagination in the religious realm. These attitudes are connected in a specific way. Since Kant was a representative of the age of reason he tried to find a rational road to God. He believed he had found this road on the plane and within the limits of moral reason. Thus a moral faith or the “faith of a moralist” ensued from his premises and took the place of true religion as well as of natural theology.

It will be our task to rehabilitate both true religion and true philosophic theology without relapsing into the errors of former standpoints, be they theistic or deistic, Platonic or Aristotelian, empiristic or rationalistic. We must carry through the original program of the philosophy of Kant: we must establish the primacy of faith by means of philosophical reflection.

• 1.

  Luther expressed strongly and often coarsely his animosity against Greek philosophy and philosophy in general. “Philosophy,” he writes as a young man, “is an old woman that stinks of Greece.”

• 2.

  I agree in principle with the intentions of Etienne Gilson as expounded in Christianity and Philosophy (1939), but I do not agree with the thesis that the medieval philosophy is the only right form of a “Christian philosophy.” On the contrary, this philosophy, as based on the ancient categories, is not yet tinged by the Christian attitude towards reason as Kant's philosophy is.

• 3.

  l.c. p. 4.

• 4.

  Cr. of P.R., B 608 (A 580).

• 5.

  l.c. B 664 (A 636).

• 6.

  This character of Protestantism has been pronounced with a new vigor in our days by Karl Barth, Reinhold Niebuhr, Paul Tillich and other theologians.

• 7.

  Met. 1074 b. Transl. by W. D. Ross, Oxford, 1928.

• 8.

  Met. 1072 a. Aristotle proclaims a kind of supremacy of thought over desire, and so a kind of supremacy of theoretical over practical activity, but this doctrine does not imply a primacy of theoretical over practical reason, instead it means the primacy of reason over desire. “Thought,” as applied to the knowledge of God and to God's nature is, according to Aristotle, not “theoretical” in the sense Kant uses the term, it is rather theoretical and practical as well. God is the highest good and the highest truth at the same time. Aristotle's theology is the result of the combination of metaphysics and ethics; both become one and the same “thought” in God.