Chapter VIII: Part 8

An explanation of Nature on a single principle, or, in other words, Monism, derives from human experience all the material which it requires for the explanation of the world. In the same way, it looks for the springs of action also within the world of observation, i.e., in that human part of Nature which is accessible to our self-observation, and more particularly in the moral imagination. Monism declines to seek outside that world the ultimate grounds of the world which we perceive and think. For Monism, the unity which reflective observation adds to the manifold multiplicity of percepts, is identical with the unity which the human desire for knowledge demands, and through which this desire seeks entrance into the physical and spiritual realms. Whoever looks for another unity behind this one, only shows that he fails to perceive the coincidence of the results of thinking with the demands of the instinct for knowledge. A particular human individual is not something cut off from the universe. He is a part of the universe, and his connection with the cosmic whole is broken, not in reality, but only for our perception. At first we apprehend the human part of the universe as a self-existing thing, because we are unable to perceive the cords and ropes by which the fundamental forces of the cosmos keep turning the wheel of our life.

All who remain at this perceptual standpoint see the part of the whole as if it were a truly independent, self-existing thing, a monad which gains all its knowledge of the rest of the world in some mysterious manner from without. But Monism has shown that we can believe in this independence only so long as thought does not gather our percepts into the network of the conceptual world. As soon as this happens, all partial existence in the universe, all isolated being, reveals itself as a mere appearance due to perception. Existence as a self-contained totality can be predicated only of the universe as a whole. Thought destroys the appearances due to perception and assigns to our individual existence a place in the life of the cosmos. The unity of the conceptual world which contains all objective percepts, has room also within itself for the content of our subjective personality. Thought gives us the true structure of reality as a self-contained unity, whereas the multiplicity of percepts is but an appearance conditioned by our organisation (cp. pp. 178 ff.). The recognition of the true unity of reality, as against the appearance of multiplicity, is at all times the goal of human thought. Science strives to apprehend our apparently disconnected percepts as a unity by tracing their inter-relations according to natural law. But, owing to the prejudice that an inter-relation discovered by human thought has only a subjective validity, thinkers have sought the true ground of unity in some object transcending the world of our experience (God, will, absolute spirit, etc.). Further, basing themselves on this prejudice, men have tried to gain, in addition to their knowledge of inter-relations within experience, a second kind of knowledge transcending experience, which should reveal the connection between empirical inter-relations and those realities which lie beyond the limits of experience (Metaphysics). The reason why, by logical thinking, we understand the nexus of the world, was thought to be that an original creator has built up the world according to logical laws, and, similarly, the ground of our actions was thought to lie in the will of this original being. It was overlooked that thinking embraces in one grasp the subjective and the objective, and that it communicates to us the whole of reality in the union which it effects between percept and concept. Only so long as we contemplate the laws which pervade and determine all percepts, in the abstract form of concepts, do we indeed deal only with something purely subjective. But this subjectivity does not belong to the content of the concept which, by means of thought, is added to the percept. This content is taken, not from the subject, but from reality. It is that part of reality which is inaccessible to perception. It is experience, but not the kind of experience which comes from perception. Those who cannot understand that the concept is something real, have in mind only the abstract form, in which we fix and isolate the concept. But in this isolation, the concept is as much dependent solely on our organisation as is the percept. The tree which I perceive, taken in isolation by itself, has no existence; it exists only as a member in the immense mechanism of Nature, and is possible only in real connection with Nature. An abstract concept, taken by itself, has as little reality as a percept taken by itself. The percept is that part of reality which is given objectively, the concept that part which is given subjectively (by intuition; cp. pp. 90 ff.). Our mental organisation breaks up reality into these two factors. The one factor is apprehended by perception, the other by intuition. Only the union of the two, which consists of the percept fitted according to law into its place in the universe, is reality in its full character. If we take mere percepts by themselves, we have no reality but only a disconnected chaos. If we take the laws which determine percepts by themselves, we have nothing but abstract concepts. Reality is not to be found in the abstract concept. It is revealed to the contemplative act of thought which regards neither the concept by itself nor the percept by itself, but the union of both.

Even the most orthodox Idealist will not deny that we live in the real world (that, as real beings, we are rooted in it); but he will deny that our knowledge, by means of its ideas, is able to grasp reality as we live it. As against this view, Monism shows that thought is neither subjective nor objective, but a principle which holds together both these sides of reality. The contemplative act of thought is a cognitive process which belongs itself to the sequence of real events. By thought we overcome, within the limits of experience itself, the one-sidedness of mere perception. We are not able by means of abstract conceptual hypotheses (purely conceptual speculation) to puzzle out the nature of the real, but in so far as we find for our percepts the right concepts we live in the real. Monism does not seek to supplement experience by something unknowable (transcending experience), but finds reality in concept and percept. It does not manufacture a metaphysical system out of pure concepts, because it looks upon concepts as only one side of reality, viz., the side which remains hidden from perception, but is meaningless except in union with percepts. But Monism gives man the conviction that he lives in the world of reality, and has no need to seek beyond the world for a higher reality. It refuses to look for Absolute Reality anywhere but in experience, because it recognises reality in the very content of experience. Monism is satisfied with this reality, because it knows that our thought points to no other. What Dualism seeks beyond the world of experience, that Monism finds in this world itself. Monism shows that our knowledge grasps reality in its true nature, not in a purely subjective image. It holds the conceptual content of the world to be identical for all human individuals (cp. pp. 84 ff.). According to Monistic principles, every human individual regards every other as akin to himself, because it is the same world-content which expresses itself in all. In the single conceptual world there are not as many concepts of "lion" as there are individuals who form the thought of "lion," but only one. And the concept which A adds to the percept of "lion" is identical with B's concept except so far as, in each case, it is apprehended by a different perceiving subject (cp. p. 85). Thought leads all perceiving subjects back to the ideal unity in all multiplicity, which is common to them all. There is but one ideal world, but it realises itself in human subjects as in a multiplicity of individuals. So long as man apprehends himself merely by self-observation, he looks upon himself as this particular being, but so soon as he becomes conscious of the ideal world which shines forth within him, and which embraces all particulars within itself, he perceives that the Absolute Reality lives within him. Dualism fixes upon the Divine Being as that which permeates all men and lives in them all. Monism finds this universal Divine Life in Reality itself. The ideal content of another subject is also my content, and I regard it as a different content only so long as I perceive, but no longer when I think. Every man embraces in his thought only a part of the total world of ideas, and so far, individuals are distinguished one from another also by the actual contents of their thought. But all these contents belong to a self-contained whole, which comprises within itself the thought-contents of all men. Hence every man, in so far as he thinks, lays hold of the universal Reality which pervades all men. To fill one's life with such thought-content is to live in Reality, and at the same time to live in God. The thought of a Beyond owes its origin to the misconception of those who believe that this world cannot have the ground of its existence in itself. They do not understand that, by thinking, they discover just what they demand for the explanation of the perceptual world. This is the reason why no speculation has ever produced any content which has not been borrowed from reality as it is given to us. A personal God is nothing but a human being transplanted into the Beyond. Schopenhauer's Will is the human will made absolute. Hartmann's Unconscious, made up of idea and will, is but a compound of two abstractions drawn from experience. Exactly the same is true of all other transcendent principles.

The truth is that the human mind never transcends the reality in which it lives. Indeed, it has no need to transcend it, seeing that this world contains everything that is required for its own explanation. If philosophers declare themselves finally content when they have deduced the world from principles which they borrow from experience and then transplant into an hypothetical Beyond, the same satisfaction ought to be possible, if these same principles are allowed to remain in this world to which they belong anyhow. All attempts to transcend the world are purely illusory, and the principles transplanted into the Beyond do not explain the world any better than the principles which are immanent in it. When thought understands itself, it does not demand any such transcendence at all, for there is no thought-content which does not find within the world a perceptual content, in union with which it can form a real object. The objects of imagination, too, are contents which have no validity, until they have been transformed into ideas that refer to a perceptual content. Through this perceptual content they have their place in reality. A concept the content of which is supposed to lie beyond the world which is given to us, is an abstraction to which no reality corresponds. Thought can discover only the concepts of reality; in order to find reality itself, we need also perception. An Absolute Being for which we invent a content, is a hypothesis which no thought can entertain that understands itself. Monism does not deny ideal factors; indeed, it refuses to recognise as fully real a perceptual content which has no ideal counterpart, but it finds nothing within the whole range of thought that is not immanent within this world of ours. A science which restricts itself to a description of percepts, without advancing to their ideal complements, is, for Monism, but a fragment. But Monism regards as equally fragmentary all abstract concepts which do not find their complement in percepts, and which fit nowhere into the conceptual net that embraces the whole perceptual world. Hence it knows no ideas referring to objects lying beyond our experience and supposed to form the content of purely hypothetical Metaphysics. Whatever mankind has produced in the way of such ideas Monism regards as abstractions from experience, whose origin in experience has been overlooked by their authors.

Just as little, according to Monistic principles, are the ends of our actions capable of being derived from the Beyond. So far as we can think them, they must have their origin in human intuition. Man does not adopt the purposes of an objective (transcendent) being as his own individual purposes, but he pursues the ends which his own moral imagination sets before him. The idea which realises itself in an action is selected by the agent from the single ideal world and made the basis of his will. Consequently his action is not a realisation of commands which have been thrust into this world from the Beyond, but of human intuitions which belong to this world. For Monism there is no ruler of the world standing outside of us and determining the aim and direction of our actions. There is for man no transcendent ground of existence, the counsels of which he might discover, in order thence to learn the ends to which he ought to direct his action. Man must rest wholly upon himself. He must himself give a content to his action. It is in vain that he seeks outside the world in which he lives for motives of his will. If he is to go at all beyond the satisfaction of the natural instincts for which Mother Nature has provided, he must look for motives in his own moral imagination, unless he finds it more convenient to let them be determined for him by the moral imagination of others. In other words, he must either cease acting altogether, or else act from motives which he selects for himself from the world of his ideas, or which others select for him from that same world. If he develops at all beyond a life absorbed in sensuous instincts and in the execution of the commands of others, then there is nothing that can determine him except himself. He has to act from a motive which he gives to himself and which nothing else can determine for him except himself. It is true that this motive is ideally determined in the single world of ideas; but in actual fact it must be selected by the agent from that world and translated into reality. Monism can find the ground for the actual realisation of an idea through human action only in the human being himself. That an idea should pass into action must be willed by man before it can happen. Such a will consequently has its ground only in man himself. Man, on this view, is the ultimate determinant of his action. He is free.

1. ADDITION TO THE REVISED EDITION (1918).

In the second part of this book the attempt has been made to justify the conviction that freedom is to be found in human conduct as it really is. For this purpose it was necessary to sort out, from the whole sphere of human conduct, those actions with respect to which unprejudiced self-observation may appropriately speak of freedom. These are the actions which appear as realisations of ideal intuitions. No other actions will be called free by an unprejudiced observer. However, open-minded self-observation compels man to regard himself as endowed with the capacity for progress on the road towards ethical intuitions and their realisation. Yet this open-minded observation of the ethical nature of man is, by itself, insufficient to constitute the final court of appeal for the question of freedom. For, suppose intuitive thinking had itself sprung from some other essence; suppose its essence were not grounded in itself, then the consciousness of freedom, which issues from moral conduct, would prove to be a mere illusion. But the second part of this book finds its natural support in the first part, which presents intuitive thinking as an inward spiritual activity which man experiences as such. To appreciate through experience this essence of thinking is equivalent to recognising the freedom of intuitive thinking. And once we know that this thinking is free, we know also the sphere within which will may be called free. We shall regard man as a free agent, if on the basis of inner experience we may attribute to the life of intuitive thinking a self-sustaining essence. Whoever cannot do this will be unable to discover any wholly unassailable road to the belief in freedom. The experience to which we here refer reveals in consciousness intuitive thinking, the reality of which does not depend merely on our being conscious of it. Freedom, too, is thereby revealed as the characteristic of all actions which issue from the intuitions of consciousness.

2. ADDITION TO THE REVISED EDITION (1918).

The argumentation of this book is built up on the fact of intuitive thinking, which may be experienced in a purely spiritual way, and which every perception inserts into reality so that reality comes thereby to be known. All that this book aimed at presenting was the result of a survey from the basis of our experience of intuitive thinking. However, the intention also was to emphasise the systematic interpretation which this thinking, as experienced by us, demands. It demands that we shall not deny its presence in cognition as a self-sustaining experience. It demands that we acknowledge its capacity for experiencing reality in co-operation with perception, and that we do not make it seek reality in a world outside experience and accessible only to inference, in the face of which human thinking would be only a subjective activity.

This view characterises thinking as that factor in man through which he inserts himself spiritually into reality. (And, strictly, no one should confuse this kind of world-view, which is based on thinking as directly experienced, with mere Rationalism.) But, on the other hand, the whole tenor of the preceding argumentation shows that perception yields a determination of reality for human knowledge only when it is taken hold of in thinking. Outside of thinking there is nothing to characterise reality for what it is. Hence we have no right to imagine that sense-perception is the only witness to reality. Whatever comes to us by way of perception on our journey through life, we cannot but expect. The only point open to question would be whether, from the exclusive point of view of thinking as we intuitively experience it, we have a right to expect that over and above sensuous perception there is also spiritual perception. This expectation is justified. For, though intuitive thinking is, on the one hand, an active process taking place in the human mind, it is, on the other hand, also a spiritual perception mediated by no sense-organ. It is a perception in which the percipient is himself active, and a self-activity which is at the same time perceived. In intuitive thinking man enters a spiritual world also as a percipient. Whatever within this world presents itself to him as percept in the same way in which the spiritual world of his own thinking so presents itself, that is recognised by him as constituting a world of spiritual perception. This world of spiritual perception we may suppose to be standing in the same relation to thinking as does, on the sensuous side, the world of sense-perception. Man does not experience the world of spiritual perception as an alien something, because he is already familiar in his intuitive thinking with an experience of purely spiritual character. With such a world of spiritual perception a number of the writings are concerned which I have published since this present book appeared. The Philosophy of Spiritual Activity lays the philosophical foundation for these later writings. For it attempts to show that in the very experience of thinking, rightly understood, we experience Spirit. This is the reason why it appears to the author that no one will stop short of entering the world of spiritual perception who has been able to adopt, in all seriousness, the point of view of the Philosophy of Spiritual Activity. True, logical deduction--by syllogisms--will not extract out of the contents of this book the contents of the author's later books. But a living understanding of what is meant in this book by "intuitive thinking" will naturally prepare the way for living entry into the world of spiritual perception.

TRUTH AND SCIENCE [15]

I

PRELIMINARY OBSERVATIONS

Theory of Knowledge aims at being a scientific investigation of the very fact which all other sciences take for granted without examination, viz., knowing or knowledge-getting itself. To say this is to attribute to it, from the very start, the character of being the fundamental philosophical discipline. For, it is only this discipline which can tell us what value and significance belong to the insight gained by the other sciences. In this respect it is the foundation for all scientific endeavour. But, it is clear that the Theory of Knowledge can fulfil its task only if it works without any presuppositions of its own, so far as that is possible in view of the nature of human knowledge. This is probably conceded on all sides. And yet, a more detailed examination of the better-known epistemological systems reveals that, at the very starting-point of the inquiry, there is made a whole series of assumptions which detract considerably from the plausibility of the rest of the argument. In particular, it is noticeable how frequently certain hidden assumptions are made in the very formulation of the fundamental problems of epistemology. But, if a science begins by misstating its problems, we must despair from the start of finding the right solution. The history of the sciences teaches us that countless errors, from which whole epochs have suffered, are to be traced wholly and solely to the fact that certain problems were wrongly formulated. For illustrations there is no need to go back to Aristotle or to the Ars Magna Lulliana. There are plenty of examples in more recent times. The numerous questions concerning the purposes of the rudimentary organs of certain organisms could be correctly formulated only after the discovery of the fundamental law of biogenesis had created the necessary conditions. As long as Biology was under the influence of teleological concepts, it was impossible to put these problems in a form permitting a satisfactory answer. What fantastic ideas, for example, were current concerning the purpose of the so-called pineal gland, so long as it was fashionable to frame biological questions in terms of "purpose." An answer was not achieved until the solution of the problem was sought by the method of Comparative Anatomy, and scientists asked whether this organ might not be merely a residual survival in man from a lower evolutionary level. Or, to mention yet another example, consider the modifications in certain physical problems after the discovery of the laws of the mechanical equivalents of heat and of the conservation of energy! In short, the success of scientific investigations depends essentially upon the investigator's ability to formulate his problems correctly. Even though the Theory of Knowledge, as the presupposition of all other sciences, occupies a position very different from theirs, we may yet expect that for it, too, successful progress in its investigations will become possible only when the fundamental questions have been put in the correct form.

The following discussions aim, in the first place, at such a formulation of the problem of knowledge as will do justice to the character of the Theory of Knowledge as a discipline which is without any presuppositions whatever. Their secondary aim is to throw light on the relation of J. G. Fichte's Wissenschaftslehre to such a fundamental philosophical discipline. The reason why precisely Fichte's attempt to provide an absolutely certain basis for the sciences will be brought into closer relation with our own philosophical programme, will become clear of itself in the course of our investigation.

II

THE FUNDAMENTAL PROBLEM OF KANT'S THEORY OF KNOWLEDGE

It is usual to designate Kant as the founder of the Theory of Knowledge in the modern sense. Against this view it might plausibly be argued that the history of philosophy records prior to Kant numerous investigations which deserve to be regarded as something more than mere beginnings of such a science. Thus Volkelt, in his fundamental work on the Theory of Knowledge, [16] remarks that the critical treatment of this discipline took its origin already with Locke. But in the writings of even older philosophers, yes, even in the philosophy of Ancient Greece, discussions are to be found which at the present day are usually undertaken under the heading of Theory of Knowledge. However, Kant has revolutionised all problems under this head from their very depths up, and, following him, numerous thinkers have worked them through so thoroughly that all the older attempts at solutions may be found over again either in Kant himself or else in his successors. Hence, for the purposes of a purely systematic, as distinct from a historical, study of the Theory of Knowledge, there is not much danger of omitting any important phenomenon by taking account only of the period since Kant burst upon the world with his Critique of Pure Reason. All previous epistemological achievements are recapitulated during this period.

The fundamental question of Kant's Theory of Knowledge is, How are synthetic judgments a priori possible? Let us consider this question for a moment in respect of its freedom from presuppositions. Kant asks the question precisely because he believes that we can attain unconditionally certain knowledge only if we are able to prove the validity of synthetic judgments a priori. He says: "Should this question be answered in a satisfactory way, we shall at the same time learn what part reason plays in the foundation and completion of those sciences which contain a theoretical a priori knowledge of objects;" [17] and, further, "Metaphysics stands and falls with the solution of this problem, on which, therefore, the very existence of Metaphysics absolutely depends." [18]

Are there any presuppositions in this question, as formulated by Kant? Yes, there are. For the possibility of a system of absolutely certain knowledge is made dependent on its being built up exclusively out of judgments which are synthetic and acquired independently of all experience. "Synthetic" is Kant's term for judgments in which the concept of the predicate adds to the concept of the subject something which lies wholly outside the subject, "although it stands in some connection with the subject," [19] whereas in "analytic" judgments the predicate affirms only what is already (implicitly) contained in the subject. This is not the place for considering the acute objections which Johannes Rehmke [20] brings forward against this classification of judgments. For our present purpose, it is enough to understand that we can attain to genuine knowledge only through judgments which add to one concept another the content of which was not, for us at least, contained in that of the former. If we choose to call this class of judgments, with Kant, "synthetic," we may agree that knowledge in judgment form is obtainable only where the connection of predicate and subject is of this synthetic sort. But, the case is very different with the second half of Kant's question, which demands that these judgments are to be formed a priori, i.e., independently of all experience. For one thing, it is altogether possible [21] that such judgments do not occur at all. At the start of the Theory of Knowledge we must hold entirely open the question, whether we arrive at any judgments otherwise than by experience, or only by experience. Indeed, to unprejudiced reflection the alleged independence of experience seems from the first to be impossible. For, let the object of our knowledge be what it may--it must, surely, always present itself to us at some time in an immediate and unique way; in short, it must become for us an experience. Mathematical judgments, too, are known by us in no other way than by our experiencing them in particular concrete cases. Even if, with Otto Liebmann, [22] for example, we treat them as founded upon a certain organisation of our consciousness, this empirical character is none the less manifest. We shall then say that this or that proposition is necessarily valid, because the denial of its truth would imply the denial of our consciousness, but the content of a proposition can enter our knowledge only by its becoming an experience for us in exactly the same way in which a process in the outer world of nature does so. Let the content of such a proposition include factors which guarantee its absolute validity, or let its validity be based on other grounds--in either case, I can possess myself of it only in one way and in no other: it must be presented to me in experience. This is the first objection to Kant's view.

The other objection lies in this, that we have no right, at the outset of our epistemological investigations, to affirm that no absolutely certain knowledge can have its source in experience. Without doubt, it is easily conceivable that experience itself might contain a criterion guaranteeing the certainty of all knowledge which has an empirical source.

Thus, Kant's formulation of the problem implies two presuppositions. The first is that we need, over and above experience, another source of cognitions. The second is that all knowledge from experience has only conditional validity. Kant entirely fails to realise that these two propositions are open to doubt, that they stand in need of critical examination. He takes them over as unquestioned assumptions from the dogmatic philosophy of his predecessors and makes them the basis of his own critical inquiries. The dogmatic thinkers assume the validity of these two propositions and simply apply them in order to get from each the kind of knowledge which it guarantees. Kant assumed their validity and only asks, What are the conditions of their validity? But, what if they are not valid at all? In that case, the edifice of Kantian doctrine lacks all foundation whatever.

The whole argumentation of the five sections which precede Kant's formulation of the problem, amounts to an attempt to prove that the propositions of Mathematics are synthetic. [23] But, precisely the two presuppositions which we have pointed out are retained as mere assumptions in his discussions. In the Introduction to the Second Edition of the Critique of Pure Reason we read, "experience can tell us that a thing is so and so, but not that it cannot be otherwise," and, "experience never bestows on its judgments true or strict universality, but only the assumed and relative universality of induction." [24] In Prologomena, [25] we find it said, "First, as regards the sources of metaphysics, the very concept of Metaphysics implies that they cannot be empirical. The principles of Metaphysics (where the term 'principles' includes, not merely its fundamental propositions, but also its fundamental concepts), can never be gained from experience, for the knowledge of the metaphysician has precisely to be, not physical, but 'metaphysical,' i.e., lying beyond the reach of experience." Lastly Kant says in the Critique of Pure Reason: "The first thing to notice is, that no truly mathematical judgments are empirical, but always a priori. They carry necessity on their very face, and therefore cannot be derived from experience. Should anyone demur to this, I am willing to limit my assertion to the propositions of Pure Mathematics, which, as everybody will admit, are not empirical judgments, but perfectly pure a priori knowledge." [26]

We may open the Critique of Pure Reason wherever we please, we shall always find that in all its discussions these two dogmatic propositions are taken for granted. Cohen [27] and Stadler [28] attempt to prove that Kant has established the a priori character of the propositions of Mathematics and Pure Natural Science. But all that Kant tries to do in the Critique may be summed up as follows. The fact that Mathematics and Pure Natural Science are a priori sciences implies that the "form" of all experience has its ground in the subject. Hence, all that is given by experience is the "matter" of sensations. This matter is synthesised by the forms, inherent in the mind, into the system of empirical science. It is only as principles of order for the matter of sense that the formal principles of the a priori theories have function and significance. They make empirical science possible, but they cannot transcend it. These formal principles are nothing but the synthetic judgments a priori, which therefore extend, as conditions of all possible empirical knowledge, as far as that knowledge but no further. Thus, the Critique of Pure Reason, so far from proving the a priori character of Mathematics and Pure Natural Science, does but delimit the sphere of their applicability on the assumption that their principles must become known independently of experience. Indeed, Kant is so far from attempting a proof of the a priori character of these principles, that he simply excludes that part of Mathematics (see the quotation above) in which, even according to his view, that character might be called in question, and confines himself to the part in which he thinks he can infer the a priori character from the bare concepts involved. Johannes Volkelt, too, comes to the conclusion that "Kant starts from the explicit presupposition" that "there actually does exist knowledge which is universal and necessary." He goes on to remark, "This presupposition which Kant has never explicitly questioned, is so profoundly contradictory to the character of a truly critical Theory of Knowledge, that the question must be seriously put whether the Critique is to be accepted as critical Theory of Knowledge at all." Volkelt does, indeed, decide that there are good grounds for answering this question in the affirmative, but still, as he says, "this dogmatic assumption does disturb the critical attitude of Kant's epistemology in the most far-reaching way." [29] In short, Volkelt, too, finds that the Critique of Pure Reason is not a Theory of Knowledge free from all assumptions.

In substantial agreement with our view are also the views of O. Liebmann, [30] Holder, [31] Windelband, [32] Ueberweg, [33] Eduard von Hartmann, [34] and Kuno Fischer, [35] all of whom acknowledge that Kant makes the a priori character of Pure Mathematics and Physics the basis of his whole argumentation.

The propositions that we really have knowledge which is independent of all experience, and that experience can furnish knowledge of only relative universality, could be accepted by us as valid only if they were conclusions deduced from other propositions. It would be absolutely necessary for these propositions to be preceded by an inquiry into the essential nature of experience, as well as by another inquiry into the essential nature of knowing. The former might justify the first, the latter the second, of the above two propositions.

It would be possible to reply to the objections which we have urged against the Critique of Pure Reason, as follows. It might be said that every Theory of Knowledge must first lead the reader to the place where the starting-point, free from all presuppositions, is to be found. For, the knowledge which we have at any given moment of our lives is far removed from this starting-point, so that we must first be artificially led back to it. Now, it is true that some such mutual understanding between author and reader concerning the starting-point of the science is necessary in all Theory of Knowledge. But such an understanding ought on no account to go beyond showing how far the alleged starting-point of knowing is truly such. It ought to consist of purely self-evident, analytic propositions. It ought not to lay down any positive, substantial affirmations which influence, as in Kant, the content of the subsequent argumentation. Moreover, it is the duty of the epistemologist to show that the starting-point which he alleges is really free from all presuppositions. But all this has nothing to do with the essential nature of that starting-point. It lies wholly outside the starting-point and makes no affirmations about it. At the beginning of mathematical instruction, too, the teacher must exert himself to convince the pupil of the axiomatic character of certain principles. But no one will maintain that the content of the axioms is in any way made dependent on these prior discussions of their axiomatic character. [36] In exactly the same way, the epistemologist, in his introductory remarks, ought to show the method by which we can reach a starting-point free from all presuppositions. But the real content of the starting-point ought to be independent of the reflections by which it is discovered. There is, most certainly, a wide difference between such an introduction to the Theory of Knowledge and Kant's way of beginning with affirmations of quite definite, dogmatic character.

III

THEORY OF KNOWLEDGE SINCE KANT

Kant's mistaken formulation of the problem has had a greater or lesser influence on all subsequent students of the Theory of Knowledge. For Kant, the view that all objects which are given to us in experience are ideas in our minds is a consequence of his theory of the a priori. For nearly all his successors, it has become the first principle and starting-point of their epistemological systems. It is said that the first and most immediate truth is, simply and solely, the proposition that we know our own ideas. This has come to be a well-nigh universal conviction among philosophers. G. E. Schulze maintains in his Ænesidemus, as early as 1792, that all our cognitions are mere ideas and that we can never transcend our ideas. Schopenhauer puts forward, with all the philosophical pathos which distinguishes him, the view that the permanent achievement of Kant's philosophy is the thesis that "the world is my idea." To Eduard von Hartmann this thesis is so incontestable, that he addresses his treatise, Kritische Grundlegung des Transcendentalen Realismus, exclusively to readers who have achieved critical emancipation from the naïve identification of the world of perception with the thing-in-itself. He demands of them that they shall have made clear to themselves the absolute heterogeneity of the object of perception which through the act of representation has been given as a subjective and ideal content of consciousness, and of the thing-in-itself which is independent of the act of representation and of the form of consciousness and which exists in its own right. His readers are required to be thoroughly convinced that the whole of what is immediately given to us consists of ideas. [37] In his latest work on Theory of Knowledge, Hartmann does, indeed, attempt to give reasons for this view. What value should be attached to these reasons by an unprejudiced Theory of Knowledge will appear in the further course of our discussions. Otto Liebmann posits as the sacrosanct first principle of the Theory of Knowledge the proposition, "Consciousness cannot transcend itself." [38] Volkelt has called the proposition that the first and most immediate truth is the limitation of all our knowledge, in the first instance, to our own ideas exclusively, the positivistic principle of knowledge. He regards only those theories of knowledge as "in the fullest sense critical" which "place this principle, as the only fixed starting-point of philosophy, at the head of their discussions and then consistently think out its consequences." [39] Other philosophers place other propositions at the head of the Theory of Knowledge, e.g., the proposition that its real problem concerns the relation between Thought and Being, and the possibility of a mediation between them; [40] or that it concerns the way in which Being becomes an object of Consciousness; [41] and many others. Kirchmann starts from two epistemological axioms, "Whatever is perceived is," and, "Whatever is self-contradictory, is not." [42] According to E. L. Fischer, knowledge is the science of something actual, something real, [43] and he criticises this dogma as little as does Goering who asserts similarly, "To know means always to know something which is. This is a fact which cannot be denied either by scepticism or by Kant's critical philosophy." [44] These two latter thinkers simply lay down the law: This is what knowledge is. They do not trouble to ask themselves with what right they do it.

But, even if these various propositions were correct, or led to correct formulations of the problem, it would still be impossible to discuss them at the outset of the Theory of Knowledge. For, they all belong, as positive and definite cognitions, within the realm of knowledge. To say that my knowledge extends, in the first instance, only to my ideas, is to express in a perfectly definite judgment something which I know. In this judgment I qualify the world which is given to me by the predicate "existing in the form of idea." But how am I to know, prior to all knowledge, that the objects given to me are ideas?

The best way to convince ourselves of the truth of the assertion that this proposition has no right to be put at the head of the Theory of Knowledge, is to retrace the way which the human mind must follow in order to reach this proposition, which has become almost an integral part of the whole modern scientific consciousness. The considerations which have led to it are systematically summarised, with approximate exhaustiveness, in Part I of Eduard von Hartmann's treatise, Das Grundproblem der Erkenntnistheorie. His statement, there, may serve as a sort of guiding-thread for us in our task of reviewing the reasons which may lead to the acceptance of this proposition.

These reasons are physical, psycho-physical, physiological, and properly philosophical.

The Physicist is led by observation of the phenomena which occur in our environment when, e.g., we experience a sensation of sound, to the view that there is nothing in these phenomena which in the very least resembles what we perceive immediately as sound. Outside, in the space which surrounds us, nothing is to be found except longitudinal oscillations of bodies and of the air. Thence it is inferred that what in ordinary life we call "sound" or "tone" is nothing but the subjective reaction of our organism to these wave-like oscillations. Similarly, it is inferred that light and colour and heat are purely subjective. The phenomena of colour-dispersion, of refraction, of interference, of polarisation, teach us that to the just-mentioned sensations there correspond in the outer space certain transverse oscillations which we feel compelled to ascribe, in part to the bodies, in part to an immeasurably fine, elastic fluid, the "ether." Further, the Physicist is driven by certain phenomena in the world of bodies to abandon the belief in the continuity of objects in space, and to analyse them into systems of exceedingly minute particles (molecules, atoms), the size of which, relatively to the distances between them, is immeasurably small. Thence it is inferred that all action of bodies on each other is across the empty intervening space, and is thus a genuine actio in distans. The Physicist believes himself justified in holding that the action of bodies on our senses of touch and temperature does not take place through direct contact, because there must always remain a definite, if small, distance between the body and the spot on the skin which it is said to "touch." Thence it is said to follow that what we sense as hardness or heat in bodies is nothing but the reactions of the end-organs of our touch- and temperature-nerves to the molecular forces of bodies which act upon them across empty space.

These considerations from the sphere of Physics are supplemented by the Psycho-physicists with their doctrine of specific sense-energies. J. Müller has shown that every sense can be affected only in its own characteristic way as determined by its organisation, and that its reaction is always of the same kind whatever may be the external stimulus. If the optical nerve is stimulated, light-sensations are experienced by us regardless of whether the stimulus was pressure, or an electric current, or light. On the other hand, the same external phenomena produce quite different sensations according as they are perceived by different senses. From these facts the inference has been drawn that there occurs only one sort of phenomenon in the external world, viz., motions, and that the variety of qualities of the world we perceive is essentially a reaction of our senses to these motions. According to this view, we do not perceive the external world as such, but only the subjective sensations which it evokes in us.

Physiology adds its quota to the physical arguments. Physics deals with the phenomena which occur outside our organisms and which correspond to our percepts. Physiology seeks to investigate the processes which go on in man's own body when a certain sensation is evoked in him. It teaches us that the epidermis is wholly insensitive to the stimuli in the external world. Thus, e.g., if external stimuli are to affect the end-organs of our touch-nerves on the surface of our bodies, the oscillations which occur outside our bodies have to be transmitted through the epidermis. In the case of the senses of hearing and of sight, the external motions have, in addition, to be modified by a number of structures in the sense-organs, before they reach the nerves. The nerves have to conduct the effects produced in the end-organs up to the central organ, and only then can take place the process by means of which purely mechanical changes in the brain produce sensations. It is clear that the stimulus which acts upon the sense-organs is so completely changed by the transformations which it undergoes, that every trace of resemblance between the initial impression on the sense-organs and the final sensation in consciousness must be obliterated. Hartmann sums up the outcome of these considerations in these words: "This content of consciousness consists, originally, of sensations which are the reflex responses of the soul to the molecular motions in the highest cortical centres, but which have not the faintest resemblance to the molecular motions by which they are elicited."

If we think this line of argument through to the end, we must agree that, assuming it to be correct, there survives in the content of our consciousness not the least element of what may be called "external existence."

To the physical and physiological objections against so-called "Naïve Realism" Hartmann adds some further objections which he describes as philosophical in the strict sense. A logical examination of the physical and physiological objections reveals that, after all, the desired conclusion can be reached only if we start from the existence and nexus of external objects, just as these are assumed by the ordinary naïve consciousness, and then inquire how this external world can enter the consciousness of beings with organisms such as ours. We have seen that every trace of such an external world is lost on the way from the impression on the sense-organ to the appearance of the sensation in our consciousness, and that in the latter nothing survives except our ideas. Hence, we have to assume that the picture of the external world which we actually have, has been built up by the soul on the basis of the sensations given to it. First, the soul constructs out of the data of the senses of touch and sight a picture of the world in space, and then the sensations of the other senses are fitted into this space-system. When we are compelled to think of a certain complex of sensations as belonging together, we are led to the concept of substance and regard substance as the bearer of sense-qualities. When we observe that some sense-qualities disappear from a substance and that others appear in their place, we ascribe this event in the world of phenomena to a change regulated by the law of causality. Thus, according to this view, our whole world-picture is composed of subjective sensations which are ordered by the activity of our own souls. Hartmann says, "What the subject perceives is always only modifications of its own psychic states and nothing else." [45]

Now let us ask ourselves, How do we come by such a view? The bare skeleton of the line of thought which leads to it is as follows. Supposing an external world exists, we do not perceive it as such but transform it through our organisation into a world of ideas. This is a supposition which, when consistently thought out, destroys itself. But is this reflection capable of supporting any positive alternative? Are we justified in regarding the world, which is given to us, as the subjective content of ideas because the assumptions of the naïve consciousness, logically followed out, lead to this conclusion? Our purpose is, rather, to exhibit these assumptions themselves as untenable. Yet, so far we should have found only that it is possible for a premise to be false and yet for the conclusion drawn from it to be true. Granted that this may happen, yet we can never regard the conclusion as proved by means of that premise.

It is usual to apply the title of "Naïve Realism" to the theory which accepts as self-evident and indubitable the reality of the world-picture which is immediately given to us. The opposite theory, which regards this world as merely the content of our consciousness, is called "Transcendental Idealism." Hence, we may sum up the outcome of the above discussion by saying, "Transcendental Idealism demonstrates its own truth, by employing the premises of the Naïve Realism which it seeks to refute." Transcendental Idealism is true, if Naïve Realism is false. But the falsity of the latter is shown only by assuming it to be true. Once we clearly realise this situation, we have no choice but to abandon this line of argument and to try another. But are we to trust to good luck, and experiment about until we hit by accident upon the right line? This is Eduard von Hartmann's view when he believes himself to have shown the validity of his own epistemological standpoint, on the ground that his theory explains the phenomena whereas its rivals do not. According to his view, the several philosophical systems are engaged in a sort of struggle for existence in which the fittest is ultimately accepted as victor. But this method appears to us to be unsuitable, if only for the reason that there may well be several hypotheses which explain the phenomena equally satisfactorily. Hence, we had better keep to the above line of thought for the refutation of Naïve Realism, and see where precisely its deficiency lies. For, after all, Naïve Realism is the view from which we all start out. For this reason alone it is advisable to begin by setting it right. When we have once understood why it must be defective, we shall be led upon the right path with far greater certainty than if we proceed simply at haphazard.