Scholasticism is in the highest degree a product of human ingenuity. In it the logical faculty celebrated its greatest triumphs. One who aims to elaborate concepts in their sharpest and clearest contours should serve an apprenticeship with the Scholastics. It is they who provide the highest schooling for the technique of thinking. They have an incomparable agility in moving in the field of pure thought. It is easy to underestimate what they were capable of accomplishing in this field. For in most areas of learning the latter is accessible to man only with difficulty. Most people attain it clearly only in the realms of counting, of arithmetic, and in thinking about the properties of geometric forms. We can count by adding a unit to a number in our thoughts, without calling sensory images to our help. We also calculate without such images, in the pure element of thought alone. As for geometric forms, we know that they do not completely coincide with any sensory image. In the reality of the senses there exists no (conceptual) circle. And yet our thinking occupies itself with the latter. For objects and processes which are more complicated than numerical and spatial structures, it is more difficult to find conceptual counterparts. This has led to the claim made in some quarters that there is only as much real knowledge in the various fields of investigation as there is that in them which can be measured and counted. This is as decidedly wrong as is anything one-sided; but it seduces many, as often only something one-sided can. Here the truth is that most people are not capable of grasping purely conceptually when it is no longer a matter of something measurable or countable. But one who cannot do this in connection with higher realms of life and knowledge resembles in this respect a child who has not yet learned to count in any other way than by adding one pea to another. The thinker who said that there is as much true knowledge in any field of learning as there is mathematics in it, did not grasp the full truth of the matter. One must require that everything which cannot be measured and counted is to be treated in the same conceptual fashion as numerical and spatial structures. And this requirement was respected by the Scholastics in the highest degree. Everywhere they sought the conceptual content of things, just as the mathematician seeks it in the area of the measurable and countable.
In spite of this accomplished logical skill, the Scholastics attained only a one-sided and subordinate concept of cognition. According to this concept, in the process of cognition man produces in himself an image of what he is to grasp. It is quite obvious that with such a concept of cognition, one must place all reality outside of cognition. For in the process of cognition one cannot then grasp a thing itself, but only an image of this thing. Man also cannot grasp himself in his self-knowledge; what he grasps of himself is only an image of his self. It is quite in the spirit of Scholasticism that someone who is closely acquainted with it says (K. Werner in his Franz Suarez und die Scholastik der letzten Jahrhunderte [Francisco Suarez and the Scholasticism of the Last Centuries], p. 122): “In time man has no perception of his self, the hidden foundation of his spiritual nature and life; ... he will never be able to look at himself; for either, forever estranged from God, he will find in himself only a bottomless dark abyss and endless emptiness, or he will, blessed in God, and turning his gaze inward, find only God, Whose sun of grace shines within him, and Whose image reflects itself in the spiritual traits of his nature.” One who thinks about all cognition in this way has only a concept of that cognition which is applicable to external things. What is sensory in a thing always remains external to us. Therefore into our cognition we can only receive images of what is sensory in the world. When we perceive a color or a stone we cannot ourselves become color or stone in order to know the nature of the color or of the stone. And neither can the color or the stone transform itself into a part of our own nature. But it must be asked: Is the concept of such a cognition, focused as it is upon the external in things, an exhaustive one? — It is true that for Scholasticism all human cognition coincides in its essentials with this cognition. Another writer who knows Scholasticism extremely well (Otto Willmann, in his Geschichte des Idealismus [History of Idealism], V. 2, 2nd ed., p. 396) characterizes the concept of cognition of this philosophy in the following way: “Our spirit, associated with the body as it is in earthly life, is primarily directed toward the surrounding world of matter, but focused upon the spiritual in it; that is, the essences, natures, and forms of things, the elements of existence which are akin to it and provide it with the rungs by which it ascends to the super-sensory; the field of our cognition is thus the realm of experience, but we should learn to understand what it offers, penetrate to its sense and idea, and thereby open to ourselves the world of ideas.” The Scholastic could not attain a different concept of cognition. He was prevented from doing so by the dogmatic teaching of his theology. If he had fixed his spiritual eye upon what he considered to be a mere image, he would have seen that the spiritual content of things reveals itself in this supposed image; he would then have found that God does not merely reflect Himself within him, but that He lives in him, is present in him in His essence. In looking within himself he would not have beheld a dark abyss, an endless emptiness, nor merely an image of God; rather would he have felt that a life pulses in him which is the divine life itself, and that his own life is the life of God. This the Scholastic could not admit. In his opinion God could not enter into him and speak out of him; He could only exist in him as an image. In reality, the Divinity had to be presupposed outside the self. Thus it had to reveal itself through supernatural communications from the outside, and could not do so within, through the spiritual life. But what is intended by this is exactly what is least achieved. It is the highest possible concept of the Divinity which is to be attained. In reality, the Divinity is degraded to a thing among other things, but these other things reveal themselves to man in a natural manner, through experience, while the Divinity is to reveal Itself to him supernaturally. However, a difference between the cognition of the Divine and of the creation is made in saying that, as concerns the creation, the external thing is given in the experience, that one has knowledge of it. As concerns the Divine, the object is not given in the experience; one can only attain it through faith. Thus for the Scholastic the highest things are not objects of knowledge, but only of faith. It is true that, according to the Scholastic view, the relationship of knowledge to faith is not to be imagined in such a way that in a certain field only knowledge reigns, in another only faith. For “cognition of the existing is possible for us, because it originates in a creative cognition; things are for the spirit because they are from the spirit; they tell us something because they have a meaning which a higher intelligence has put into them.” (O. Willmann, Geschichte des Idealismus, V. 2, p. 383.) Since God has created the world according to His ideas, if we grasp the ideas of the world, we can also grasp the traces of the Divine in the world through scientific reflection. But what God is in His essence we can only grasp through the revelation which He has given us in a supernatural manner, and in which we must believe. What we must think concerning the highest things is not decided by any human knowledge, but by faith; and “to faith belongs everything that is contained in the Scriptures of the New and Old Covenant, and in the divine traditions.” (Joseph Kleutgen, Die Theologie der Vorzeit [The Theology of Antiquity], V. 1, p. 39.) — We cannot make it our task here to describe in detail and to explain the relationship of the content of faith to that of knowledge. In reality, the content of all faith originates in an inner experience man has had at some time. It is then preserved, according to its external import, without the consciousness of how it was acquired. It is said of it that it came into the world through supernatural revelation. The content of the Christian faith was simply accepted by the Scholastics as tradition. Science and inner experience were not allowed to claim any rights over it. Scholasticism could no more permit itself to create a concept of God than science can create a tree; it had to accept the revealed concept as given, just as natural science accepts the tree as given. The Scholastic could never admit that the spiritual itself shines and lives within man. He therefore drew a limit to the jurisdiction of science where the field of external experience ends. Human cognition could not be permitted to produce a concept of the higher entities out of itself. It was to accept a revealed one. That in doing this it actually only accepted one which had been produced at an earlier stage of human spiritual life, and declared it to be a revealed one, this the Scholastics could not admit. — In the course of the development of Scholasticism therefore, all those ideas had disappeared from it which still indicated the manner in which man has produced the concepts of the Divine in a natural way. In the first centuries of the development of Christianity, at the time of the Fathers of the Church, we see how the content of the teachings of theology came into being little by little through the inclusion of inner experiences. This content is still treated entirely as an inner experience by Johannes Scotus Erigena, who stood at the height of Christian theological learning in the ninth century. Among the Scholastics of the succeeding centuries this quality of an inner experience is completely lost; the old content is reinterpreted as the content of an external, supernatural revelation. — One can therefore interpret the activity of the mystical theologians Eckhart, Tauler, Suso, and their companions by saying: They were inspired by the content of the teachings of the Church, which is contained in theology, but had been reinterpreted, to bring forth a similar content out of themselves anew as an inner experience.
The most important concept of the spiritual life of Nicolas is that of “learned ignorance.” By this he understands a cognition which represents a higher level, as opposed to ordinary knowledge. Knowledge in the subordinate sense is the grasping of an object by the spirit. The most important characteristic of knowledge is that it gives information about something outside the spirit, that is, that it looks at something which it itself is not. In knowledge, the spirit thus is occupied with things thought of as being outside of it. But what the spirit forms in itself concerning things is the essence of things. Things are spirit. At first man sees the spirit only through the sensory covering. What remains outside the spirit is only this sensory covering; the essence of things enters into the spirit. When the spirit then looks upon this essence, which is substance of its substance, it can no longer speak of knowledge, for it does not look upon a thing which is outside of it; it looks upon a thing which is a part of itself; it looks upon itself. It no longer knows; it only looks upon itself. It is not concerned with a “knowing,” but with a “not-knowing.” It no longer grasps something through the spirit; it “beholds, without grasping,” its own life. This highest level of cognition, in relation to the lower levels, is a “not-knowing.” — It will be seen that the essence of things can only be communicated through this level of cognition. With his “learned not-knowing” Nicolas of Cusa thus speaks of nothing but the knowledge reborn as inner experience. He himself tells how he came to have this inner experience. “I made many attempts to unite my thoughts about God and the world, about Christ and the Church in one fundamental idea, but of them all none satisfied me until finally, during the return from Greece by sea, the gaze of my spirit lifted itself, as if through an inspiration from on high, to the view in which God appeared to me as the highest unity of all contrasts.” To a greater or lesser extent the influences which derive from a study of his predecessors are involved in this inspiration. In his way of thinking one recognizes a peculiar renewal of the ideas we encounter in the writing of a certain Dionysius. Scotus Erigena, mentioned above, had translated this work into Latin. He calls the author “the great and divine revealer.” These writings were first mentioned in the first half of the sixth century. They were ascribed to that Dionysius the Aeropagite mentioned in the Acts of the Apostles, who was converted to Christianity by Paul. Here we shall not go into the problem as to when these writings were really composed. Their contents had a strong effect on Nicolas, as they already had on Johannes Scotus Erigena, and as they must also have been stimulating in many respects for the way of thinking of Eckhart and his companions. The “learned not-knowing” is prefigured in a certain way in these writings. Here we shall record only the main feature of the way of thinking of these writings. Man first comes to know the things of the sensory world. He reflects on their existence and activity. The primordial foundation of all things must lie higher than the things themselves. Man therefore cannot expect to grasp this primordial foundation with the same concepts and ideas as he grasps the things themselves. If therefore he attributes to the primordial foundation (God) qualities which he knows from lower things, these qualities can only be auxiliary ideas of the weak spirit, which draws the primordial foundation down to itself in order to be able to imagine it. In reality, therefore, no quality which lower things have can be said to belong to God. It cannot even be said that God is. For “being” too is a concept which man has formed in connection with lower things. But God is exalted above “being” and “not-being.” Thus the God to Whom we ascribe qualities is not the true one. We arrive at the true God if we imagine a “Supergod” above a God with such qualities. Of this “Supergod” we can know nothing in the ordinary sense. In order to reach Him, “knowing” must flow into “not-knowing.” — One can see that such a view is based on the consciousness that out of what his sciences have furnished him man himself — in a purely natural way — can develop a higher cognition, which is no longer mere knowledge. The Scholastic view declared knowledge to be incapable of such a development, and at the point where knowledge is supposed to end, it had faith, based on an external revelation, come to the aid of knowledge. — Nicolas of Cusa thus was on the way toward once again developing that out of knowledge which the Scholastics had declared to be unattainable for cognition.
From the point of view of Nicolas of Cusa, therefore, one cannot say that there is only one kind of cognition. Cognition, on the contrary, is clearly divided into what mediates a knowledge of external things, and what is itself the object of which one acquires knowledge. The former kind of cognition rules in the sciences which we acquire concerning the things and processes of the sensory world; the latter kind is in us when we ourselves live in what has been acquired. The second kind of cognition develops from the first. Yet it is the same world to which both kinds of cognition refer, and it is the same man who shares in both. The question must arise, How does it come about that one and the same man develops two kinds of cognition of one and the same world? — The direction in which the answer to this question is to be sought was already indicated in our discussion of Tauler. Here this answer can be formulated even more definitely with regard to Nicolas of Cusa. First of all, man lives as a separate (individual) being among other separate beings. To the influences which the other beings exercise upon one another, in him is added the faculty of (lower) cognition. Through his senses he receives impressions of the other beings, and he works upon these impressions with his spiritual faculties. He directs his spiritual gaze away from external things and looks at himself, at his own activity. Thus self-knowledge arises in him. As long as he remains upon this level of self-knowledge he does not yet look upon himself in the true sense of the word. He can still believe that there is some hidden entity active within him, and that what appears to him as his activity are only the manifestations and actions of this entity. But the point can come at which it becomes clear to man through an incontrovertible inner experience that in what he perceives and experiences within himself he possesses not the manifestation, the action, of a hidden force or entity, but this entity itself in its primordial form. He can then say to himself: All other things I encounter in a way ready-made, and I, who stand outside them, add to them what the spirit has to say with regard to them. But in what I myself thus creatively add to things in myself, in that I myself live, that is what I am, that is my own essence. But what is it that speaks in the depths of my spirit? It is knowledge that speaks, the knowledge I have acquired about the things of the world. But in this knowledge it is not some action, some manifestation, which speaks; something speaks which keeps nothing back of what it has in itself. In this knowledge speaks the world in all its immediacy. But I have acquired this knowledge from things and from myself, as from a thing among things. Out of my own essence it is I myself and the things who speak. In reality I no longer merely express my nature; I express the nature of things. My “I” is the form, the organ, through which things declare themselves with regard to themselves. I have gained the experience that I experience my own essence within myself, and for me this experience becomes enlarged into another: that in me and through me the universal essence expresses itself, or, in other words, knows itself. Now I can no longer feel myself to be a thing among things; I can only feel myself to be a form in which the universal essence has its life. — It is therefore only natural that one and the same man should have two kinds of cognition. With regard to the sensory facts he is a thing among things, and, insofar as this is the case, he acquires a knowledge of these things; but at any moment he can have the higher experience that he is the form in which the universal essence looks upon itself. Then he himself is transformed from a thing among things into a form of the universal essence — and with him the knowledge of things is changed into an utterance of the nature of things. This transformation, however, can in fact be accomplished only by man himself. What is mediated in the higher cognition is not yet present as long as this higher cognition itself is not present. It is only in creating this higher cognition that man develops his nature, and only through the higher cognition of man does the nature of things come into actual existence. If therefore it is required that man should not add anything to the things of the senses through his higher cognition, but should express only what already lies in them in the outside world, then this simply means renouncing all higher cognition. — From the fact that, as regards his sensory life, man is a thing among things, and that he only attains higher cognition when as a sensory being he himself accomplishes his transformation into a higher being, from this it follows that he can never replace the one cognition by the other. Rather, his spiritual life consists of a perpetual moving to and fro between the two poles of cognition, between knowing and seeing. If he shuts himself off from seeing, he forgoes the nature of things; if he were to shut himself off from sensory knowing, he would deprive himself of the things whose nature he wants to understand. — The same things reveal themselves to the lower understanding and to the higher seeing, only they do this at one time with regard to their external appearance, at the other time with regard to their inner essence. — Thus it is not due to things themselves that at a certain stage they appear only as external objects; rather it is due to the fact that man must first transform himself to the point where he can reach the stage at which things cease to be external.
It is only with these considerations in mind that certain views natural science elaborated in the nineteenth century appear in their proper light. The adherents of these views say to themselves: We hear, see, and touch the things of the material world through the senses. The eye, for instance, communicates to us a phenomenon of light, a color. We say that a body emits red light when, by the mediation of our eye, we have the sensation “red.” But the eye gives us this sensation in other cases too. If it is struck or pressed, if an electric current passes through the head, the eye has a sensation of light. Hence in those instances also in which we have the sensation that a body emits light of a certain color, something may be occurring in that body which does not have any resemblance to color. No matter what is occurring in outside space, as long as this process is suitable for making an impression upon the eye, a sensation of color arises in me. What we perceive arises in us because we have organs that are constituted in a certain way. What goes on in outside space remains outside of us; we know only the effects which external processes bring forth in us. Hermann Helmholtz (1821–1894) has given expression to this idea in a clearly defined way. “Our perceptions are effects produced in our organs by external causes, and the way such an effect manifests itself is of course substantially dependent on the kind of apparatus acted upon. Insofar as the quality of our perception gives us information about the characteristics of the external influence by which it is caused, it can be considered as a sign of the latter, but not as a likeness of it. For of an image one requires some kind of similarity to the object represented: of a statue, similarity of form; of a drawing, similarity of the perspective projection in the field of view; of a painting, in addition to this, similarity of colors. But a sign need not have any kind of resemblance to that of which it is a sign. The relationship between the two is limited to this, that the same object, exercising its influence under the same circumstances, calls forth the same sign, and that therefore unlike signs always correspond to unlike influences ... If in ripening berries of a certain variety develop both a red pigment and sugar, then red color and sweet taste will always be found together in our perception of berries of this kind.” (cf. Helmholtz: Die Tatsachen der Wahrnehmung [The Facts of Perception], p. 12 f.) I have characterized this way of thinking in detail in my Philosophie der Freiheit [Philosophy of Spiritual Activity] and in my Rätsel der Philosophie [Riddles of Philosophy], 1918. — Let us now follow step by step the train of thought which is adopted in this view. A process is assumed in outside space. It produces an effect upon my sensory organ; my nervous system transmits to my brain the impression produced. Another process is effected there. I now perceive “red.” Now it is said: The perception of “red” is thus not outside; it is in me. All our perceptions are only signs of external processes, the real character of which we know nothing. We live and act among our perceptions, and know nothing about their origin. In line with this way of thinking one can also say: If we had no eye there would be no color; nothing would then transform the external process, which is unknown to us, into the perception “red.” For many this train of thought is something seductive. Nevertheless it rests upon a complete misinterpretation of the facts under consideration. (If many contemporary natural scientists and philosophers were not deluded to a truly monstrous degree by this train of thought, one would not have to talk about it so much. But this delusion has in fact vitiated contemporary thinking in many respects.) Since man is a thing among things, it is of course necessary that things should make an impression upon him if he is to find out anything about them. A process outside of man must give rise to a process in man if the phenomenon “red” is to appear in the field of vision. One must only ask: What is outside, what inside? Outside is a process which takes place in space and time. But inside doubtless is a similar process. Such a process exists in the eye and communicates itself to the brain when I perceive “red.” I cannot directly perceive the process which is “inside,” any more than I can immediately perceive the wave motion “outside,” which physicists consider corresponds to the color “red.” But it is only in this sense that I can speak of an “outside” and an “inside.” Only on the level of sensory perception does the contrast between “outside” and “inside” have any validity. This perception leads me to assume a spatial-temporal process “outside,” although I cannot perceive it directly. And, further, the same perception leads me to assume such a process within me, although I cannot perceive it directly either. But, after all, I also assume spatial-temporal processes in ordinary life which I cannot directly perceive. For example, I hear a piano being played in the next room. Therefore I assume that a human being with spatial dimensions sits at the piano and plays. And my way of representing things to myself is no different when I speak of processes within me and outside of me. I assume that these processes have characteristics analogous to those of the processes which fall within the domain of my senses, only that, for certain reasons, they are not accessible to my direct observation. If I were to deny to these processes all those qualities my senses show me in the realm of the spatial and the temporal, I would in truth be imagining something like the famous knife without a handle of which the blade is missing. Thus I can only say that “outside” occur spatial-temporal processes, and that they cause spatial-temporal processes “inside.” Both are necessary if “red” is to appear in my field of vision. Insofar as it is not spatial-temporal I shall look for this red in vain, no matter whether I look for it “outside” or “inside.” The natural scientists and philosophers who cannot find it “outside” should not attempt to look for it “inside” either. It is not “inside,” in the same sense in which it is not “outside.” To declare that the entire content of what the world of the senses presents to us is an inner world of perceptions, and to look for something “external” corresponding to it, is an impossible idea. Therefore we cannot say that “red,” “sweet,” “hot,” etc. are signs which, as such, are only caused to arise in us and to which something quite different on the “outside” corresponds. For what is really caused in us as the effect of an external process is something quite different from what appears in the field of our perceptions. If one wants to call what is in us signs, then one can say: These signs appear within our organism in order to communicate perceptions to us which, as such, in their immediacy are neither inside nor outside us, but rather belong to that common world of which my “external world” and my “interior world” are only parts. It is true that in order to be able to grasp this common world I must raise myself to that higher level of cognition for which an “inside” and an “outside” no longer exist. (I am well aware that people who rely on the gospel that “our entire world of experience” is made up of sensations of unknown origin will look down haughtily upon this exposition, in somewhat the same way as Dr. Erich Adikes in his work Kant contra Haeckel says condescendingly: “For the time being, people like Haeckel and thousands of his kind philosophize merrily on, without worrying about any theory of cognition or about critical introspection.” Such gentlemen of course have no suspicion of how paltry their theories of cognition are. They suspect a lack of critical introspection only in others. We shall not begrudge them their “wisdom.”)
It is just on the point under consideration here that Nicolas of Cusa has excellent ideas. His keeping the lower and the higher cognition clearly separated from each other permits him on the one hand to gain a full insight into the fact that as a sensory being man can have within himself only processes which must, as effects, be unlike the corresponding external processes; on the other hand, it preserves him from confusing the inner processes with the facts which appear in our field of perception and which, in their immediacy, are neither outside nor inside, but are elevated above this contrast. — Nicolas was “prevented by his priestly cloth” from following without reservations the path which this insight indicated to him. We see him making a good beginning with the advance from “knowing” to “not-knowing.” But at the same time we must observe that in the field of “not-knowing” he has nothing to show except the theological teachings which are offered to us by the Scholastics also. It is true that he knows how to develop this theological content in an ingenious manner: on providence, Christ, the creation of the world, man's redemption, the moral life, he presents teachings which are altogether in line with dogmatic Christianity. It would have been in keeping with his spiritual direction to say: I have confidence that human nature, having immersed itself in the sciences of things on all sides, is able from within itself to transform this “knowing” into a “not-knowing,” hence that the highest cognition brings satisfaction. Then he would not have accepted, as he has, the traditional ideas of soul, immortality, redemption, God, creation, the Trinity, etc., but would have upheld those which he himself had found. — But Nicolas, personally was so penetrated with the concepts of Christianity that he could well believe he was awakening his own proper “not-knowing” within himself, while he was only putting forth the traditional views in which he had been educated. — However, it must be considered that he was standing before a fateful abyss in human spiritual life. He was a scientific man. And science at first removes man from the innocent concord in which he exists with the world as long as the conduct of his life is a purely naïve one. In such a conduct of life man dimly feels his connection with the totality of the universe. He is a being like others, integrated into the chain of natural effects. With knowledge, he separates himself from this whole. He creates a spiritual world within himself. With it he confronts nature in solitude. He has become richer, but this wealth is a burden which he bears with difficulty. For at first it weighs upon him alone. He must find the way back to nature through his own resources. He must understand that now he himself must integrate his wealth into the chain of universal effects, as nature herself had integrated his poverty before. It is here that all the evil demons lie in wait for man. His strength can easily fail. Instead of accomplishing the integration himself, when this occurs, he will take refuge in a revelation from the outside, which again delivers him from his solitude, and leads the knowledge he feels to be a burden back into the primordial origin of existence, the Divinity. He will think, as did Nicolas of Cusa, that he is walking his own road, while in reality he will only find the one his spiritual development has shown him. Now, there are three roads — in the main — upon which one can walk when one arrives where Nicolas had arrived: one is positive faith, which comes to us from outside; the second is despair: one stands alone with one's burden and feels all existence tottering with oneself; the third road is the development of man's own deepest faculties. Confidence in the world must be one leader along this third road. Courage to follow this confidence, no matter where it leads, must be the other.