SECTION II. Time

TIME

METAPHYSICAL EXPOSITION OF THE CONCEPTION OF TIME

=Time: First Argument.=--This argument is in all respects the same as the first argument on space. The thesis is that the representation of time is not of empirical origin. The proof is based on the fact that this representation must be previously given in order that the perception of coexistence or succession be possible. It also runs on all fours with the first argument in the Dissertation.

“The idea of time does not originate in, but is presupposed by the senses. When a number of things act upon the senses, it is only by means of the idea of time that they can be represented whether as simultaneous or as successive. Nor does succession generate the conception of time; but stimulates us to form it. Thus the notion of time, even if acquired through experience, is very badly defined as being a series of actual things existing one after another. For I can understand what the word after signifies only if I already know what time means. For those things are after one another which exist at different times, as those are simultaneous which exist at one and the same time.”

=Second Argument.=--Kant again applies to time the argument already employed by him in dealing with space. The thesis is that time is given a priori. Proof is found in the fact that it cannot be thought away, i.e. in the fact of its subjective necessity. From this subjective necessity follows its objective necessity, so far as all appearances are concerned. In the second edition Kant added a phrase--“as the general condition of their possibility”--which is seriously misleading. The concluding sentence is thereby made to read as if Kant were arguing from the objective necessity of time, i.e. from its necessity as a constituent in the appearances apprehended, to its apriority. It is indeed possible that Kant himself regarded this objective necessity of time as contributing to the proof of its apriority. But no such argument can be accepted. Time may be necessary to appearances, once appearances are granted. This does not, however, prove that it must therefore precede them a priori. This alteration in the second edition is an excellent, though unfortunate, example of Kant’s invincible carelessness in the exposition of his thought. It has contributed to a misreading by Herbart and others of this and of the corresponding argument on space.

“Let us not talk of an absolute space as the presupposition of all our constructed figures. Possibility is nothing but thought, and it arises only when it is thought. Space is nothing but possibility, for it contains nothing save images of the existent; and absolute space is nothing save the abstracted general possibility of such constructions, abstracted from it after completion of the construction. The necessity of the representation of space ought never to have played any rôle in philosophy. To think away space is to think away the possibility of that which has been previously posited as actual. Obviously that is impossible, and the opposite is necessary.”

Were Kant really arguing here and in the second argument on space solely from the objective necessity of time and space, this criticism would be unanswerable. But even taking the argument in its first edition form, as an argument from the psychological necessity of time, it lies open to the same objection as the argument on space. It rests upon a false statement of fact. We cannot retain time in the absence of all appearances of outer and inner sense. With the removal of the given manifold, time itself must vanish.

=Fourth Argument.=--This argument differs only slightly, and mainly through omissions, from the fourth of the arguments in regard to space; but a few minor points call for notice. (a) In the first sentence, instead of intuition, which alone is under consideration in its contrast to conception, Kant employs the phrase “pure form of intuition.” (b) In the third sentence Kant uses the quite untenable phrase “given through a single object (Gegenstand).” Time is not given from without, nor is it due to an object. (c) The concluding sentences properly belong to the transcendental exposition. They are here introduced, not in the ambiguous manner of the fourth argument on space, but explicitly as a further argument in proof of the intuitive character of time. The synthetic proposition which Kant cites is taken neither from the science of motion nor from arithmetic. It expresses the nature of time itself, and for that reason is immediately contained in the intuition of time.

=Fifth Argument.=--This argument differs fundamentally from the corresponding argument on space, whether of the first or of the second edition, and must therefore be independently analysed. The thesis is again that time is an intuition. Proof is derived from the fact that time is a representation in which the parts arise only through limitation, and in which, therefore, the whole must precede the parts. The original (ursprüngliche) time-representation, i.e. the fundamental representation through limitation of which the parts arise as secondary products, must be an intuition.

To this argument Kant makes two explanatory additions. (a) As particular times arise through limitation of one single time, time must in its original intuition be given as infinite, i.e. as unlimited. The infinitude of time is not, therefore, as might seem to be implied by the prominence given to it, and by analogy with the final arguments of both the first and the second edition, a part of the proof that it is an intuition, but only a consequence of the feature by which its intuitive character is independently established. The unwary reader, having in mind the corresponding argument on space, is almost inevitably misled. All reference to infinitude could, so far as this argument is concerned, have been omitted. The mode in which the argument opens seems indeed to indicate that Kant was not himself altogether clear as to the cross-relations between the arguments on space and time respectively. The real parallel to this argument is to be found in the second part of the fourth argument on space. That part was omitted by Kant in his fourth argument on time, and is here developed into a separate argument. This is, of course, a further cause of confusion to the reader, who is not prepared for such arbitrary rearrangement. Indeed it is not surprising to find that when Kant became the reader of his own work, in preparing it for the second edition, he was himself misled by the intricate perversity of his exposition. In re-reading the argument he seems to have forgotten that it represents the second part of the fourth argument on space. Interpreting it in the light of the fifth argument on space which he had been recasting for the second edition, it seemed to him possible, by a slight alteration, to bring this argument on time into line with that new proof. This unfortunately results in the perverting of the entire paragraph. The argument demands an opposition between intuition in which the whole precedes the parts, and conception in which the parts precede the whole. In order to bring the opposition into line with the new argument on space, according to which a conception contains an infinite number of parts, not in it, but only under it, Kant substitutes for the previous parenthesis the statement that “concepts contain only partial representations,” meaning, apparently, that their constituent elements are merely abstracted attributes, not real concrete parts, or in other words, not strictly parts at all, but only partial representations. But this does not at all agree with the context. The point at issue is thereby obscured.

(b) The main argument rests upon and presupposes a very definite view as to the manner in which alone, according to Kant, concepts are formed. Only if this view be granted as true of all concepts without exception is the argument cogent. This doctrine of the concept is accordingly stated by Kant in the words of the parenthesis. The partial representations, i.e. the different properties which go to constitute the object or content conceived, precede the representation of the whole. “The aggregation of co-ordinate attributes (Merkmale) constitutes the totality of the concept.” Upon the use which Kant thus makes of the traditional doctrine of the concept, and upon its lack of consistency with his recognition of relational categories, we have already dwelt.

=Third Argument and the Transcendental Exposition.=--The third argument ought to have been omitted in the second edition, and its substance incorporated in the new transcendental exposition, as was done with the corresponding argument concerning space. The excuse which Kant offers for not making the change, namely, his desire for brevity, is not valid. By insertion in the new section the whole matter could have been stated just as briefly as before.

The purpose of the transcendental exposition has been already defined. It is to show how time, when viewed in the manner required by the results of the metaphysical deduction, as an a priori intuition, renders synthetic a priori judgments possible.

This exposition, as it appears in the third argument of the first edition, grounds the apodictic character of two axioms in regard to time on the proved apriority of the representation of time, and then by implication finds in these axioms a fresh proof of the apriority of time.

The new transcendental exposition extends the above by two further statements: (a) that only through the intuition of time can any conception of change, and therewith of motion (as change of place), be formed; and (b) that it is because the intuition of time is an a priori intuition that the synthetic a priori propositions of the “general doctrine of motion” are possible. To take each in turn. (a) Save by reference to time the conception of motion is self-contradictory. It involves the ascription to one and the same thing of contradictory predicates, e.g. that an object both is and is not in a certain place. From this fact, that time makes possible what is not possible in pure conception, Kant, in his earlier rationalistic period, had derived a proof of the subjectivity of time. (b) In 1786 in the Metaphysical First Principles of Natural Science Kant had developed the fundamental principles of the general science of motion. He takes the opportunity of the second edition (1787) of the Critique to assign this place to them in his general system. The implication is that the doctrine of motion stands to time in the relation in which geometry stands to space. Kant is probably here replying, as Vaihinger has suggested, to an objection made by Garve to the first edition, that no science, corresponding to geometry, is based on the intuition of time. For two reasons, however, the analogy between mechanics and geometry breaks down. In the first place, the conception of motion is empirical; and in the second place, it presupposes space as well as time.

Kant elsewhere explicitly disavows this view that the science of motion is based on time. He had already done so in the preceding year (1786) in the Metaphysical First Principles. He there points out that as time has only one dimension, mathematics is not applicable to the phenomena of inner sense. At most we can determine in regard to them (in addition, of course, to the two axioms already cited) only the law that all these changes are continuous. Also in Kant’s Ueber Philosophie überhaupt (written some time between 1780 and 1790, and very probably in or about the year 1789) we find the following utterance:

“The general doctrine of time, unlike the pure doctrine of space (geometry), does not yield sufficient material for a whole science.”

Why, then, should Kant in 1787 have so inconsistently departed from his own teaching? This is a question to which I can find no answer. Apparently without reason, and contrary to his more abiding judgment, he here repeats the suggestion which he had casually thrown out in the Dissertation of 1770:

“Pure mathematics treats of space in geometry and of time in pure mechanics.”

But in the Dissertation the point is only touched upon in passing. The context permits of the interpretation that while geometry deals with space, mechanics deals with time in addition to space.

KANT’S VIEWS REGARDING THE NATURE OF ARITHMETICAL SCIENCE

In the Dissertation, and again in the chapter on Schematism in the Critique itself, still another view is suggested, namely, that the science of arithmetic is also concerned with the intuition of time. The passage just quoted from the Dissertation proceeds as follows:

“Pure mathematics treats of space in geometry and of time in pure mechanics. To these has to be added a certain concept which is in itself intellectual, but which demands for its concrete actualisation (actuatio) the auxiliary notions of time and space (in the successive addition and in the juxtaposition of a plurality). This is the concept of number which is dealt with in Arithmetic.”

This view of arithmetic is to be found in both editions of the Critique. Arithmetic depends upon the synthetic activity of the understanding; the conceptual element is absolutely essential.

“Our counting (as is easily seen in the case of large numbers) is a synthesis according to concepts, because it is executed according to a common ground of unity, as, for instance, the decade (Dekadik).” “The pure image ... of all objects of the senses in general is time. But the pure schema of quantity, in so far as it is a concept of the understanding, is number, a representation which combines the successive addition of one to one (homogeneous). Thus number is nothing but the unity of the synthesis of the manifold of a homogeneous intuition in general, whereby I generate time itself in the apprehension of the intuition.”

This is also the teaching of the Methodology. Now it may be observed that in none of these passages is arithmetic declared to be the science of time, or even to be based on the intuition of time. In 1783, however, in the Prolegomena, Kant expresses himself in much more ambiguous terms, for his words imply that there is a parallelism between geometry and arithmetic.

“Geometry is based upon the pure intuition of space. Arithmetic produces its concepts of number through successive addition of units in time, and pure mechanics especially can produce its concepts of motion only by means of the representation of time.”

The passage is by no means explicit; the “especially” (vornehmlich) seems to indicate a feeling on Kant’s part that the description which he is giving of arithmetic is not really satisfactory. Unfortunately this casual statement, though never repeated by Kant in any of his other writings, was developed by Schulze in his Erläuterungen.

“Since geometry has space and arithmetic has counting as its object (and counting can only take place by means of time), it is evident in what manner geometry and arithmetic, that is to say pure mathematics, is possible.”

Largely, as it would seem, through Schulze, whose Erläuterungen did much to spread Kant’s teaching, this view came to be the current understanding of Kant’s position. The nature of arithmetic, as thus popularly interpreted, is expounded by Schopenhauer in the following terms:

“In time every moment is conditioned by the preceding. The ground of existence, as law of the sequence, is thus simple, because time has only one dimension, and no manifoldness of relations can be possible in it. Every moment is conditioned by the preceding; only through the latter can we attain to the former; only because the latter was, and has elapsed, does the former now exist. All counting rests upon this nexus of the parts of time; its words merely serve to mark the single steps of the succession. This is true of the whole of arithmetic, which throughout teaches nothing but the methodical abbreviations of counting. Every number presupposes the preceding numbers as grounds of its existence; I can only reach them through all the preceding, and only by means of this insight into the ground of its existence do I know that, where ten are, there are also eight, six, four.”

Schulze was at once challenged to show that this was really Kant’s teaching, and the passage which he cited was Kant’s definition of the schema of number, above quoted. It is therefore advisable that we should briefly discuss the many difficulties which this passage involves. What does Kant mean by asserting that in the apprehension of number we generate time? Does he merely mean that time is required for the process of counting? Counting is a process through which numerical relations are discovered; and it undoubtedly occupies time. But so do all processes of apprehension, in the study of geometry no less than of arithmetic. That this is not Kant’s meaning, and that it is not even what Schulze, notwithstanding his seemingly explicit mode of statement, intends to assert, is clearly shown by a letter written by Kant to Schulze in November 1788. Schulze, it appears, had spoken of this very matter.

“Time, as you justly remark, has no influence upon the properties of numbers (as pure determinations of quantity), such as it may have upon the nature of those changes (of quantity) which are possible only in connection with a specific property of inner sense and its form (time). The science of number, notwithstanding the succession which every construction of quantity demands, is a pure intellectual synthesis which we represent to ourselves in thought. But so far as quanta are to be numerically determined, they must be given to us in such a way that we can apprehend their intuition in successive order, and such that their apprehension can be subject to time....”

No more definite statement could be desired of the fact that though in arithmetical science as in other fields of study our processes of apprehension are subject to time, the quantitative relations determined by the science are independent of time and are intellectually apprehended.

But if the above psychological interpretation of Kant’s teaching is untenable, how is his position to be defined? We must bear in mind the doctrine which Kant had already developed in his pre-Critical period, that mathematical differs from philosophical knowledge in that its concepts can have concrete individual form. In the Critique this difference is expressed in the statement that the mathematical sciences alone are able to construct their concepts. And as they are pure mathematical sciences, this construction is supposed to take place by means of the a priori manifold of space and of time. Now though Kant had a fairly definite notion of what he meant by the construction of geometrical figures in space, his various utterances seem to show that in regard to the nature of arithmetical and algebraic construction he had never really attempted to arrive at any precision of view. To judge by the passage already quoted from the Dissertation, Kant regarded space as no less necessary than time to the construction or intuition of number. ”[The intellectual concept of number] demands for its concrete actualisation the auxiliary notions of time and space (in the successive addition and in the juxtaposition of a plurality)” A similar view appears in the Critique in A 140 = B 179 and in B 15. In conformity, however, with the general requirements of his doctrine of Schematism, Kant defines the schema of number in exclusive reference to time; and, as we have noted, it is to this definition that Schulze appeals in support of his view of arithmetic as the science of counting and therefore of time. It at least shows that Kant perceived some form of connection to exist between arithmetic and time. But in this matter Kant’s position was probably simply a corollary from his general view of the nature of mathematical science, and in particular of his view of geometry, the “exemplar” of all the others. Mathematical science, as such, is based on intuition; therefore arithmetic, which is one of its departments, must be so likewise. No attempt, however, is made to define the nature of the intuitions in which it has its source. Sympathetically interpreted, his statements may be taken as suggesting that arithmetic is the study of series which find concrete expression in the order of sequent times. The following estimate, given by Cassirer, does ample justice both to the true and to the false elements in Kant’s doctrine.

”[Even discounting Kant’s insistence upon the conceptual character of arithmetical science, and] allowing that he derives arithmetical concepts and propositions from the pure intuition of time, this teaching, to whatever objections it may lie open, has certainly not the merely psychological meaning which the majority of its critics have ascribed to it. If it contained only the trivial thought, that the empirical act of counting requires time, it would be completely refuted by the familiar objection which B. Beneke has formulated: ‘The fact that time elapses in the process of counting can prove nothing; for what is there over which time does not flow?’ It is easily seen that Kant is only concerned with the ‘transcendental’ determination of the concept of time, according to which it appears as the type of an ordered sequence. William [Rowan] Hamilton, who adopts Kant’s doctrine, has defined algebra as ‘science of pure time or order in progression.’ That the whole content of arithmetical concepts can really be obtained from the fundamental concept of order in unbroken development, is completely confirmed by Russell’s exposition. As against the Kantian theory it must, of course, be emphasised, that it is not the concrete form of time intuition which constitutes the ground of the concept of number, but that on the contrary the pure logical concepts of sequence and of order are already implicitly contained and embodied in that concrete form.”

Much of the unsatisfactoriness of Kant’s argument is traceable to his mode of conceiving the “construction” of mathematical concepts. All concepts, he seems to hold, even those of geometry and arithmetic, are abstract class concepts--the concept of triangle representing the properties common to all triangles, and the concept of seven the properties common to all groups that are seven. Mathematical concepts differ, however, from other concepts in that they are capable of a priori construction, that is, of having their objects represented in pure intuition. Now this is an extremely unfortunate mode of statement. It implies that mathematical concepts have a dual mode of existence, first as abstracted, and secondly as constructed. Such a position is not tenable. The concept of seven, in its primary form, is not abstracted from a variety of particular groups of seven; it is already involved in the apprehension of each of them as being seven. Nor is it a concept that is itself constructed. It may perhaps be described as being the representation of something constructed; but that something is not itself. It represents the process or method generative of the complex for which it stands. Thus Kant’s distinction between the intuitive nature of mathematical knowledge and the merely discursive character of conceptual knowledge is at once inspired by the very important distinction between the product of construction and the product of abstraction, and yet at the same time is also obscured by the quite inadequate manner in which that latter distinction has been formulated. Kant has again adhered to the older logic even in the very act of revising its conclusions; and in so doing he has sacrificed the Critical doctrines of the Analytic to the pre-Critical teaching of the Dissertation and Aesthetic. Mathematical concepts are of the same general type as the categories; their primary function is not to clarify intuitions, but to make them possible. They are derivable from intuition only in so far as they have contributed to its constitution. If intuition contains factors additional to the concepts through which it is interpreted, these factors must remain outside the realm of mathematical science, until such time as conceptual analysis has proved itself capable of further extension.

I may now summarise this general discussion. Though Kant in the first edition of the Critique had spoken of the mathematical sciences as based upon the intuition of space and time, he had not, despite his constant tendency to conceive space and time as parallel forms of existence, based any separate mathematical discipline upon time. His definition of number, in the chapter on Schematism, had recognised the essentially conceptual character of arithmetic, and had connected it with time only in a quite indirect manner. A passage in the Prolegomena is the one place in all Kant’s writings in which he would seem to assert, though in brief and quite indefinite terms, that arithmetic is related to time as geometry is related to space. No such view of arithmetic is to be found in the second edition of the Critique. In the transcendental exposition of time, added in the second edition, only pure mechanics is mentioned. This would seem to indicate that Kant had made the above statement carelessly, without due thought, and that on further reflection he found himself unable to stand by it. The omission is the more significant in that Kant refers to arithmetic in the passages added in the second edition Introduction. The teaching of these passages, apart from the asserted necessity of appealing to fingers or points, harmonises with the view so briefly outlined in the Analytic. Arithmetic is a conceptual science; though it finds in ordered sequence its intuitional material, it cannot be adequately defined as being the science of time.

CONCLUSIONS FROM THE PRECEDING CONCEPTS

These Conclusions do not run parallel with the corresponding Conclusions in regard to space. In the first paragraph there are two differences. (a) Kant takes account of a view not considered under space, viz. that time is a self-existing substance. He rejects it on a ground which is difficult to reconcile with his recognition of a manifold of intuition as well as a manifold of sense, namely that it would then be something real without being a real object. In A 39 = B 57 and B 70 Kant describes space and time, so conceived, as unendliche Undinge. (b) Kant introduces into his first Conclusion the argument that only by conceiving time as the form of inner intuition can we justify a priori synthetic judgments in regard to objects.

=Second Paragraph (Conclusion b).=--This latter statement is repeated at the opening of the second Conclusion. The emphasis is no longer, however, upon the term “form” but upon the term “inner”; and Kant proceeds to make assertions which by no means follow from the five arguments, and which must be counted amongst the most difficult and controversial tenets of the whole Critique. (a) Time is not a determination of outer appearances. For it belongs neither to their shape nor to their position--and prudently at this point the property of motion is smuggled out of view under cover of an etc. Time does not determine the relation of appearances to one another, but only the relation of representations in our inner state. It is the form only of the intuition of ourselves and of our inner state. Obviously these are assertions which Kant cannot possibly hold to in this unqualified form. In the very next paragraph they are modified and restated. (b) As this inner intuition supplies no shape (Gestalt), we seek to make good this deficiency by means of analogies. We represent the time-sequence through a line progressing to infinity in which the manifold constitutes a series of only one dimension. From the properties of this line, with the one exception that its parts are simultaneous whereas those of time are always successive, we conclude to all the properties of time.

The wording of the passage seems to imply that such symbolisation of time through space is helpful but not indispensably necessary for its apprehension. That it is indispensably necessary is, however, the view to which Kant finally settled down. But he has not yet come to clearness on this point. The passage has all the signs of having been written prior to the Analytic. Though Kant seems to have held consistently to the view that time has, in or by itself, only one dimension, the difficulties involved drove him to recognise that this is true only of time as the order of our representations. It is not true of the objective time apprehended in and through our representations. When later Kant came to hold that consciousness of time is conditioned by consciousness of space, he apparently also adopted the view that, by reference to space, time indirectly acquires simultaneity as an additional mode. The objective spatial world is in time, but in a time which shows simultaneity as well as succession. In the Dissertation Kant had criticised Leibniz and his followers for neglecting simultaneity, “the most important consequence of time.”

“Though time has only one dimension, yet the ubiquity of time (to employ Newton’s term), through which all things sensuously thinkable are at some time, adds another dimension to the quantity of actual things, in so far as they hang, as it were, upon the same point of time. For if we represent time by a straight line extended to infinity, and simultaneous things at any point of time by lines successively erected [perpendicular to the first line], the surface thus generated will represent the phenomenal world both as to substance and as to accidents.”

Similarly in A 182 = B 226 of the Critique Kant states that simultaneity is not a mode of time, since none of the parts of time can be simultaneous, and yet also teaches in A 177 = B 219 that, as the order of appearances, time possesses in addition to succession the two modes, duration and simultaneity. The significance of this distinction between time as the order of our inner states, and time as the order of objective appearances, we shall consider immediately.

A connected question is as to whether or not Kant teaches the possibility of simultaneous apprehension. In the Aesthetic and Dialectic he certainly does so. Space is given as containing coexisting parts, and can be intuited as such without successive synthesis of its parts. In the Analytic, on the other hand, the opposite would seem to be implied. The apprehension of a manifold can only be obtained through the successive addition or generation of its parts.

(c) Lastly, Kant argues that the fact that all the relations of time can be expressed in an outer intuition is proof that the representation of time is itself intuition. But surely if, as Kant later taught, time can be apprehended at all only in and through space, that, taken alone, would rather be a reason for denying it to be itself intuition. In any case it is difficult to follow Kant in his contention that the intuition of time is similar in general character to that of space.

=Third Paragraph (Conclusion c).=--Kant now reopens the question as to the relation in which time stands to outer appearances. As already noted, he has argued in the beginning of the previous paragraph that it cannot be a determination of outer appearances, but only of representations in our inner state. External appearances, however, as Kant recognises, can be known only in and through representations. To that extent they belong to inner sense, and consequently (such is Kant’s argument) are themselves subject to time. Time, as the immediate condition of our representations, is also the mediate condition of appearances. Therefore, Kant concludes, “all appearances, i.e. all objects of the senses, are in time, and necessarily stand in time-relations.”

Now quite obviously this argument is invalid if the distinction between representations and their objects is a real and genuine one. For if so, it does not at all follow that because our representations of objects are in time that the objects themselves are in time. In other words, the argument is valid only from the standpoint of extreme subjectivism, according to which objects are, in Kant’s own phraseology, blosse Vorstellungen. But the argument is employed to establish a realist conclusion, that outer objects, as objects, stand in time-relations to one another. In contradiction of the previous paragraph he is now maintaining that time is a determination of outer appearances, and that it reveals itself in the motion of bodies as well as in the flux of our inner states.

The distinction between representations and their objects also makes it possible for Kant both to assert and to deny that simultaneity is a mode of time. “No two years can be coexistent. Time has only one dimension. But existence (das Dasein), measured through time, has two dimensions, succession and simultaneity.” There are, for Kant, two orders of time, subjective and objective. Recognition of the latter (emphasised and developed in the Analytic) is, however, irreconcilable with his contention that time is merely the form of inner sense.

We have here one of the many objections to which Kant’s doctrine of time lies open. It is the most vulnerable tenet in his whole system. A mere list of the points which Kant leaves unsettled suffices to show how greatly he was troubled in his own mind by the problems to which it gives rise. (1) The nature of the a priori knowledge which time yields. Kant ascribes to this source sometimes only the two axioms in regard to time, sometimes pure mechanics, and sometimes also arithmetic. (2) Whether time only allows of, or whether it demands, representation through space. Sometimes Kant makes the one assertion, sometimes the other. (3) Whether it is possible to apprehend the coexistent without successive synthesis of its parts. This possibility is asserted in the Aesthetic and Dialectic, denied in the Analytic. (4) Whether simultaneity is a mode of time. (5) Whether, and in what manner, appearances of outer sense are in time. Kant’s answer to 4 and to 5 varies according as he identifies or distinguishes representations and empirical objects.

The manifold difficulties to which a theory of time thus lies open are probably the reason why Kant, in the Critique, reverses the order in which he had treated time and space in the Dissertation. But the placing of space before time is none the less unfortunate. It greatly tends to conceal from the reader the central position which Kant has assigned to time in the Analytic. Consciousness of time is the fundamental fact, taken as bare fact, by reference to which Kant gains his transcendental proof of the categories and principles of understanding. In the Analytic space, by comparison, falls very much into the background. A further reason for the reversal may have been Kant’s Newtonian view of geometry as the mathematical science par excellence. In view of his formulation of the Critical problem as that of accounting for synthetic a priori judgments, he would then naturally be led to throw more emphasis on space.

To sum up our main conclusions. Kant’s view of time as a form merely of inner sense, and as having only one dimension, connects with his subjectivism. His view of it as inhering in objects, and as having duration and simultaneity as two of its modes, is bound up with his phenomenalism. Further discussion of these difficulties must therefore be deferred until we are in a position to raise the more fundamental problem as to the nature of the distinction between a representation and its object. Motion is not an inner state. Yet it involves time as directly as does the flow of our feelings and ideas. Kant’s assertion that “time can no more be intuited externally than space can be intuited as something in us,” if taken quite literally, would involve both the subjectivist assertion that motion of bodies is non-existent, and also the phenomenalist contention that an extended object is altogether distinct from a representation.

The fourth and fifth paragraphs call for no detailed analysis. Time is empirically real, transcendentally ideal--these terms having exactly the same meaning and scope as in reference to space. The fourth sentence in the fifth paragraph is curiously inaccurate. As it stands, it would imply that time is given through the senses. In the concluding sentences Kant briefly summarises and applies the points raised in these fourth and fifth paragraphs.

ELUCIDATION

=First and Second Paragraphs.=--Kant here replies to a criticism which, as he tells us in his letter of 1772 to Herz, was first made by Pastor Schulze and by Lambert. In that letter the objection and Kant’s reply are stated as follows.

“In accordance with the testimony of inner sense, changes are something real. But they are only possible on the assumption of time. Time is, therefore, something real which belongs to the determinations of things in themselves. Why, said I to myself, do we not argue in a parallel manner: ‘Bodies are real, in accordance with the outer senses. But bodies are possible only under the condition of space. Space is, therefore, something objective and real which inheres in the things themselves.’ The cause [of this differential treatment of space and of time] is the observation that in respect to outer things we cannot infer from the reality of representations the reality of their objects, whereas in inner sense the thought or the existing of the thought and of myself are one and the same. Herein lies the key to the difficulty. Undoubtedly I must think my own state under the form of time, and the form of the inner sensibility consequently gives me the appearance of changes. Now I do not deny that changes are something real any more than I deny that bodies are something real, but I thereby mean only that something real corresponds to the appearance. I may not even say the inner appearance undergoes change (verändere sich), for how could I observe this change unless it appeared to my inner sense? To the objection that this leads to the conclusion that all things in the world objectively and in themselves are unchangeable, I would reply that they are neither changeable nor unchangeable. As Baumgarten states in § 18 of his Metaphysica, the absolutely impossible is hypothetically neither possible nor impossible, since it cannot be mentally entertained under any condition whatsoever; so in similar manner the things of the world are objectively or in themselves neither in one and the same state nor in different states at different times, for thus understood [viz. as things in themselves] they are not represented in time at all.”

Thus Kant’s contention, both in this letter and in the passage before us, is that even our inner states would not reveal change if they could be apprehended by us or by some other being apart from the subjective form of our inner sense. We may not say that our inner states undergo change, or that they succeed one another, but only that to us they necessarily appear as so doing. Time is no more than subjectively real. As Körner writes to Schiller: “Without time man would indeed exist but not appear. Not his reality but only his appearance is dependent upon the condition of time.” “Man is not, but only appears, when he undergoes change.” The objects of inner sense stand in exactly the same position as those of outer sense. Both are appearances, and neither can be identified with the absolutely real. As Kant argues later in the Critique, inner processes are not known with any greater certainty or immediacy than are outer objects; the reality of time as subjective proves its unreality in relation to things in themselves. The statement that the constitution of things in themselves is “problematic” is an exceptional mode of expression for Kant. Usually--as indeed throughout the whole context of this passage--he asserts that though things in themselves are unknowable, we can with absolute certainty maintain that they are neither in space nor in time. Upon this point we have already dwelt in discussing Trendelenburg’s controversy with Fischer.

=Third Paragraph.=--The third and fourth paragraphs of this section ought to have had a separate heading. They summarise the total argument of the Aesthetic in regard to space as well as time, distinguish its tenets from those of Newton and of Leibniz, and draw a general conclusion. The summary follows the strict synthetic method. The opening sentences illustrate Kant’s failure to distinguish between the problems of pure and of applied mathematics, and also show how completely he tends to conceive mathematics as typified by geometry. The criticism of alternative views traverses the ground of the famous controversy between Leibniz and Clarke. Their Streitschriften were, as we have good circumstantial grounds for believing, a chief influence in the development of Kant’s own views. Kant, who originally held the Leibnizian position, was by 1768 more or less converted to the Newtonian teaching, and in the Dissertation of 1770 developed his subjectivist standpoint with the conscious intention of retaining the advantages while remedying the defects of both alternatives. For convenience we may limit the discussion to space. (a) The view propounded by Newton, and defended by Clarke, is that space has an existence in and by itself, independent alike of the mind which apprehends it and of the objects with which it is filled. (b) The view held by Leibniz is that space is an empirical concept abstracted from our confused sense-experience of the relations of real things.

The criticism of (a) is twofold. First, it involves belief in an eternal and infinite Unding. Secondly, it leads to metaphysical difficulties, especially in regard to the existence of God. If space is absolutely real, how is it to be reconciled with the omnipresence of God? Newton’s view of space as the =sensorium Dei= can hardly be regarded as satisfactory.

The objection to (b) is that it cannot account for the apodictic certainty of geometry, nor guarantee its application to experience. The concept of space, when regarded as of sensuous origin, is something that may distort (and according to the Leibnizian teaching does actually distort) what it professes to represent, and is something from which restrictions that hold in the natural world have been omitted. As empirical, it cannot serve as basis for the universal and necessary judgments of mathematical science.

The first view has, however, the advantage of keeping the sphere of appearances open for mathematical science. As space is infinite and all-comprehensive, its laws hold universally. The second view has the advantage of not subjecting reality to space conditions. These advantages are retained, while the objections are removed, by the teaching of the Aesthetic.

Kant further criticises the former view in A 46 ff. = B 64 ff. There is no possibility of accounting for the a priori synthetic judgments of geometry save by assuming that space is the pure form of outer intuition. For though the Newtonian view will justify the assertion that the laws of space hold universally, it cannot explain how we come to know them a priori. And assuming, as Kant constantly does, that space cannot be both an a priori form of intuition and also independently real, he concludes that it is the former only.

In B 71 Kant also restates the metaphysical difficulties to which the Newtonian view lies open. In natural theology we deal with an existence which can never be the object of sensuous intuition, and which has to be freed from all conditions of space and time. This is impossible if space is so absolutely real that it would remain though all created things were annihilated.

=Fourth Paragraph.=--Space and time are the only two forms of sensibility; all other concepts belonging to the senses, such as motion and change, are empirical. As Kant has himself stated, no reason can be given why space and time are the sole forms of our possible intuition:

“Other forms of intuition than space and time, ... even if they were possible, we cannot render in any way conceivable and comprehensible to ourselves, and even assuming that we could do so, they still would not belong to experience, the only kind of knowledge in which objects are given to us.”

The further statement, frequently repeated in the Critique, that time itself does not change, but only what is in time, indicates the extent to which Kant has been influenced by the Newtonian receptacle view. As Bergson very justly points out, time, thus viewed as a homogeneous medium, is really being conceived on the analogy of space. “It is merely the phantom of space obsessing the reflective consciousness.”

GENERAL OBSERVATIONS ON THE TRANSCENDENTAL AESTHETIC

=I. First Paragraph.=--“To avoid all misapprehension” Kant proceeds to state “as clearly as possible” his view of sensuous knowledge. With this end in view he sets himself to enforce two main points: (a) that as space and time are only forms of sensibility, everything apprehended is only appearance; (b) that this is not a mere hypothesis but is completely certain. Kant expounds (a) indirectly through criticism of the opposing views of Leibniz and of Locke. But before doing so he makes in the next paragraph a twofold statement of his own conclusions.

=Second Paragraph.=--This paragraph states (a) that through intuition we can represent only appearances, not things in themselves, and (b) that the appearances thus known exist only in us. Both assertions have implications, the discussion of which must be deferred to the Analytic. The mention of the “relations of things by themselves” may, as Vaihinger suggests, be a survival from the time when (as in the Dissertation) Kant sought to reduce spatial to dynamical relations. The assertion that things in themselves are completely unknown to us goes beyond what the Aesthetic can establish and what Kant here requires to prove. His present thesis is only that no knowledge of things in themselves can be acquired either through the forms of space and time or through sensation; space and time are determined solely by our pure sensibility, and sensations by our empirical sensibility. Failure to recognise this is, in Kant’s view, one of the chief defects of the Leibnizian system.

=Third and Fourth Paragraphs. Criticism of the Leibniz-Wolff Interpretation of Sensibility and of Appearance.=--Leibniz vitiates both conceptions. Sensibility does not differ from thought in clearness but in content. It is a difference of kind. They originate in different sources, and neither can by any transformation be reduced to the other.

“Even if an appearance could become completely transparent to us, such knowledge would remain toto coelo different from knowledge of the object in itself.” “Through observation and analysis of appearances we penetrate to the secrets of nature, and no one can say how far this may in time extend.... [But however far we advance, we shall never be able by means of] so ill-adapted an instrument of investigation [as our sensibility] to find anything except still other appearances, the non-sensuous cause of which we yet long to discover.”

We should still know only in terms of the two inalienable forms of our sensibility. The dualism of thought and sense can never be transcended by the human mind. By no extension of its sphere or perfecting of its insight can sensuous knowledge be transformed into a conceptual apprehension of purely intelligible entities.

Leibniz’s conception of appearances as things in themselves confusedly apprehended is equally false, and for the same reasons. Appearance and reality are related as distinct existences, each of which has its own intrinsic character and content. Through the former there can be no hope of penetrating to the latter. Appearance is subjective in matter as well as in form. For Leibniz our knowledge of appearances is a confused knowledge of things in themselves. Properly viewed, it is the apprehension, whether distinct or confused, of objects which are never things in themselves. Sense-knowledge, such as we obtain in the science of geometry, has often the highest degree of clearness. Conceptual apprehension is all too frequently characterised by obscurity and indistinctness.

This criticism of Leibniz, as expounded in these two paragraphs, is thoroughly misleading if taken as an adequate statement of Kant’s view of the relations between sense and understanding, appearance and reality. These paragraphs are really a restatement of a passage in the Dissertation.

“It will thus be seen that we express the nature of the sensuous very inappropriately when we assert that it is the more confusedly known, and the nature of the intellectual when we describe it as the distinctly known. For these are merely logical distinctions, and obviously have nothing to do with the given facts which underlie all logical comparison. The sensuous may be absolutely distinct, and the intellectual extremely confused. That is shown on the one hand in geometry, the prototype of sensuous knowledge, and on the other in metaphysics, the instrument of all intellectual enquiry. Every one knows how zealously metaphysics has striven to dispel the mists of confusion which cloud the minds of men at large and yet has not always attained the happy results of the former science. Nevertheless each of these kinds of knowledge preserves the mark of the stock from which it has sprung. The former, however distinct, is on account of its origin entitled sensuous, while the latter, however confused, remains intellectual--as e.g. the moral concepts, which are known not by way of experience, but through the pure intellect itself. I fear, however, that Wolff by this distinction between the sensuous and the intellectual, which for him is merely logical, has checked, perhaps wholly (to the great detriment of philosophy), that noblest enterprise of antiquity, the investigation of the nature of phenomena and noumena, turning men’s minds from such enquiries to what are very frequently only logical subleties.”

The paragraphs before us give expression only to what is common to the Dissertation and to the Critique, and do so entirely from the standpoint of the Dissertation. Thus the illustration of the conception of “right” implies that things in themselves can be known through the understanding. The conception, as Kant says, represents “a moral property which belongs to actions in and by themselves.” Similarly, in distinguishing the sensuous from “the intellectual,” he says that through the former we do not apprehend things in themselves, thus implying that things in themselves can be known through the pure intellect. The view developed in the Analytic, alike of sensibility and of appearance, is radically different. Sensibility and understanding may have a common source; and both are indispensably necessary for the apprehension of appearance. Neither can function save in co-operation with the other. Appearance does not differ from reality solely through its sensuous content and form, but also in the intellectual order or dispensation to which it is subject. But in the very act of thus deepening the gulf between appearance and reality by counting even understanding as contributing to the knowledge only of the former, he was brought back to a position that has kinship with the Leibnizian view of their interrelation. Since understanding is just as essential as sensibility to the apprehension of appearances, and since understanding differs from sensibility in the universality of its range, it enables us to view appearances in their relation to ultimate reality, and so to apprehend them as being, however subjective or phenomenal, ways in which the thing in itself presents itself to us. Such a view is, however, on Kant’s principles, quite consistent with the further contention, that appearance does not differ from reality in a merely logical manner. Factors that are peculiar to the realm of appearance have intervened to transform the real; and in consequence even completed knowledge of the phenomenal--if such can be conceived as possible--would not be equivalent to knowledge of things in themselves.

=Fifth Paragraph. Criticism of Locke’s View of Appearance.=--This paragraph discusses Locke’s doctrine that the secondary qualities are subjective, and that in the primary qualities we possess true knowledge of things in themselves. The distinction is drawn upon empirical grounds, namely, that while certain qualities are uniform for more than one sense, and belong to objects under all conditions, others are peculiar to the different senses, and arise only through the accidental relation of objects to the special senses. This distinction is, Kant says, entirely justified from the physical standpoint. A rainbow is an appearance of which the raindrops constitute the true empirical reality. But Locke and his followers interpret this distinction wrongly. They ignore the more fundamental transcendental (i.e. metaphysical) distinction between empirical reality and the thing in itself. From the transcendental standpoint the raindrops are themselves merely appearance. Even their round shape, and the very space in which they fall; are only modifications of our sensuous intuition. The ‘transcendental object’ remains unknown to us.

When Kant thus declares that the distinction between primary and secondary qualities is justified (richtig) from the physical standpoint, he is again speaking from a phenomenalist point of view. And it may be noted that in developing his transcendental distinction he does not describe the raindrops as mere representations. His phrase is much more indefinite. They are “modifications or fundamental forms (Grundlagen) of our sensuous intuition.”

Kant does not here criticise the view of sensibility which underlies Locke’s view of appearance. But he does so in A 271 = B 327, completing the parallel and contrast between Leibniz and Locke.

“Leibniz intellectualised appearances, just as Locke, according to his system of noogony (if I may be allowed these expressions), sensualised all concepts of the understanding, i.e. interpreted them as simply empirical or abstracted concepts of reflection. Instead of interpreting understanding and sensibility as two quite different sources of representations, which yet can supply objectively valid judgments of things only in conjunction with each other, each of these great men holds only to one of the two, viewing it as in immediate relation to things in themselves. The other faculty is regarded as serving only to confuse or to order the representations which this selected faculty yields.”

=Proof that the above View of Space and Time is not a mere Hypothesis, but completely certain.=--The proof, which as here recapitulated and developed follows the analytic method, has already been considered in connection with A 39 = B 56. It proceeds upon the assumption that space cannot be both an a priori form of intuition and also independently real. The argument as a whole lacks clearness owing to Kant’s failure to distinguish between the problems of pure and applied geometry, between pure intuition and form of intuition. This is especially obvious in the very unfortunate and misleading second application of the triangle illustration. Kant’s tendency to conceive mathematical science almost exclusively in terms of geometry is likewise illustrated.

“There is in regard to both [space and time] a large number of a priori apodictic and synthetic propositions. This is especially true of space, which for this reason will be our chief illustration in this enquiry.”

=II. Paragraphs added in the Second Edition.=--Kant proceeds to offer further proof of the ideality of the appearances (a) of outer and (b) of inner sense. Such proof he finds in the fact that these appearances consist solely of relations. (a) Outer appearances reduce without remainder to relations of position in intuition (i.e. of extension), of change of position (motion), and to the laws which express in merely relational terms the motive forces by which such change is determined. What it is that is thus present in space, or what the dynamic agencies may be to which the motion is due, is never revealed. But a real existent (Sache an sich) can never be known through mere relations. Outer sense consequently reveals through its representations only the relation of an object to the subject, not the intrinsic inner nature of the object in itself (Object an sich). Kant’s avoidance of the term Ding an sich may be noted.

(b) The same holds true of inner sense, not only because the representations of outer sense constitute its proper (eigentlichen) material, but also because time, in which these are set, contains only relations of succession, coexistence, and duration. This time (which as consisting only of relations can be nothing but a form) is itself, in turn, a mere relation. It is only the manner in which through its own activity the mind is affected by itself. But in order to be affected by itself it must have receptivity, in other words, sensibility. Time, consequently, must be regarded as the form of this inner sense.

That everything represented in time, like that which is represented in space, consists solely of relations, Kant does not, however, attempt to prove. He is satisfied with repeating the conclusion reached in the first edition of the Aesthetic, that, as time is the object of a sense, it must of necessity be appearance. This, like everything which Kant wrote upon inner sense, is profoundly unsatisfactory. The obscurities of his argument are not to be excused on the ground that “the difficulty, how a subject can have an internal intuition of itself, is common to every theory.” For no great thinker, except Locke, has attempted to interpret inner consciousness on the analogy of the senses. Discussion of the doctrine must meantime be deferred.

=III. B 69.=--Kant here formulates the important distinction between appearance (Erscheinung) and illusion (Schein). The main text is clear so far as it goes; but the appended note is thoroughly confused. Together they contain no less than three distinct and conflicting views of illusion. According to the main text, Schein signifies a representation, such as may occur in a dream, to which nothing real corresponds. Erscheinung, on the other hand, is always the appearance of a given object; but since the qualities of that object depend solely on our mode of intuition, we have to distinguish the object as appearance from the object as thing in itself.

”[Every appearance] has two sides, the one by which the object is viewed in and by itself, ... the other by which the form of the intuition of the object is taken into account....”

Obviously, when illusion is defined in the above manner, the assertion that objects in space are mere appearances cannot be taken as meaning that they are illusory.

But this view of illusion is peculiar to the passage before us and to A 38 = B 55. It occurs nowhere else, either in the Critique or in the Prolegomena; and it is not, as Kant has himself admitted, really relevant to the purposes of the Critique. The issues are more adequately faced in the appended note, which, however, at the same time, shows very clearly that Kant has not yet properly disentangled their various strands. The above definition of appearance is too wide. It covers illusory sense perception as well as appearance proper. The further qualification must be added, that the predicates of appearance are constant and are inseparable from its representation. Thus the space predicates can be asserted of any external object. Redness and scent can be ascribed to the rose. All of these are genuine appearances. If, on the other hand, the two handles, as observed by Galileo, are attributed to Saturn, roundness to a distant square tower, bentness to a straight stick inserted in water, the result is mere illusion. The predicates, in such cases, do not stand the test of further observation or of the employment of other senses. Only in a certain position of its rings, relatively to the observer, does Saturn seem (scheint) to have two handles. The distant tower only seems to be round. The stick only seems to be bent. But the rose is extended and is red. Obviously Kant is no longer viewing Schein as equivalent to a merely mental image. It now receives a second meaning. It is illusion in the modern, psychological sense. It signifies an abnormal perception of an actually present object. The distinction between appearance and illusion is now reduced to a merely relative difference in constancy and universality of appearance. Saturn necessarily appears to Galileo as possessing two handles. A square tower viewed from the distance cannot appear to the human eye otherwise than round. A stick inserted in water must appear bent. If, however, Saturn be viewed under more favourable conditions, if the distance from the tower be diminished, if the stick be removed from the water, the empirical object will appear in a manner more in harmony with the possible or actual experiences of touch. The distinction is practical, rather than theoretical, in its justification. It says only that certain sets of conditions may be expected to remain uniform; those, for instance, physical, physiological, and psychical, which cause a rose to appear red. Other sets of conditions, such as those which cause the stick to appear bent, are exceptional, and for that reason the bentness may be discounted as illusion. Among the relatively constant are the space and time properties of bodies. To employ the terms of the main text, it is not only by illusion that bodies seem to exist outside me; they actually are there.

So long as we keep to the sphere of ordinary experience, and require no greater exactitude than practical life demands, this distinction is, of course, both important and valid. But Kant, by his references to Saturn, raises considerations which, if faced, must complicate the problem and place it upon an entirely different plane. If, in view of scientific requirements, the conditions of observation are more rigorously formulated, and if by artificial instruments of scientific precision we modify the perceptions of our human senses, what before was ranked as appearance becomes illusion; and no limit can be set to the transformations which even our most normal human experiences may thus be made to undergo. Even the most constant perceptions then yield to variation. The most that can be asserted is that throughout all change in the conditions of observation objects still continue to possess, in however new and revolutionary a fashion, some kind of space and time predicates. The application of this more rigorous scientific standard of appearance thus leads to a fourfold distinction between ultimate reality, scientific appearances, the appearances of ordinary consciousness, and the illusions of ordinary consciousness. The appearances of practical life are the illusions of science, and the appearances of science would similarly be illusions to any being who through ‘intuitive understanding’ could apprehend things in themselves.

But if the distinction between appearance and illusion is thus merely relative to the varying nature of the conditions under which observation takes place, it can afford no sufficient answer to the criticisms which Kant is here professing to meet. Kant has in view those critics (such as Lambert, Mendelssohn, and Garve) who had objected that if bodies in space are representations existing, as he so often asserts, only “within us,” their appearing to exist “outside us” is a complete illusion. These critics have, indeed, found a vulnerable point in Kant’s teaching. The only way in which he can effectively meet it is by frank recognition and development of the phenomenalism with which his subjectivism comes into so frequent conflict. That certain perceptions are more constant than others does not prove that all alike may not be classed as illusory. The criticism concerns only the reality of extended objects. From Kant’s own extreme subjectivist position they are illusions of the most thoroughgoing kind. If, as Kant so frequently maintains, objects are representations and exist only “within us,” their existence “outside us” must be denied. The criticism can be met only if Kant is prepared consistently to formulate and defend his own alternative teaching, that sensations arise through the action of external objects upon the sense-organs, and that the world of physical science has consequently a reality not reducible to mere representations in the individual mind.

It may be objected that Kant has in the main text cited one essential difference between his position and that which is being ascribed to him. Extended objects, though mere representations, are yet due to, and conditioned by, things in themselves. They are illusory only in regard to their properties, not in regard to their existence. But this distinction is not really relevant. The criticism, as just stated, is directed only against Kant’s view of space. The fact that the spatial world is a grounded and necessary illusion is not strictly relevant to the matter in dispute. Kant has, indeed, elsewhere, himself admitted the justice of the criticism. In A 780 = B 808 he cites as a possible hypothesis, entirely in harmony with his main results, though not in any degree established by them, the view

“that this life is an appearance only, that is, a sensuous representation of purely spiritual life, and that the whole sensible world is a mere image (ein blosses Bild) which hovers before our present mode of knowledge, and like a dream has in itself no objective reality.”

Kant’s reply is thus really only verbal. He claims that illusion, if constant, has earned the right to be called appearance. He accepts the criticism, but restates it in his own terms. The underlying phenomenalism which colours the position in his own thoughts, and for which he has not been able to find any quite satisfactory formulation, is the sole possible justification, if any such exists, for his contention that the criticism does not apply. Such phenomenalism crops out in the sentence, already partially quoted:

“If I assert that the quality of space and time, according to which, as a condition of their existence, I posit both external objects and my own soul, lies in my mode of intuition and not in these objects in themselves, I am not saying that only by illusion do bodies seem to exist outside me or my soul to be given in my self-consciousness.”

But, so far, I have simplified Kant’s argument by leaving out of account a third and entirely different view of illusion which is likewise formulated in the appended note. In the middle of the second sentence, and in the last sentence, illusion is defined as the attribution to the thing in itself of what belongs to it only in its relation to the senses. Illusion lies not in the object apprehended, but only in the judgment which we pass upon it. It is due, not to sense, but to understanding. Viewing illusion in this way, Kant is enabled to maintain that his critics are guilty of “an unpardonable and almost intentional misconception,” since this is the very fallacy which he himself has been most concerned to attack. As he has constantly insisted, appearance is appearance just because it can never be a revelation of the thing in itself.

Now the introduction of this third view reduces the argument of the appended note to complete confusion. Its first occurrence as a parenthesis in a sentence which is stating an opposed view would seem to indicate that the note has been carelessly recast. Originally containing only a statement of the second view, Kant has connected therewith the view which he had already formulated in the first edition and in the Prolegomena. But the two views cannot be combined. By the former definition, illusion is necessitated but abnormal perception; according to the latter, it is a preventable error of our conscious judgment. The opposite of illusion is in the one case appearance, in the other truth. The retention of the reference to Saturn, in the statement of the third view at the end of the note, is further evidence of hasty recasting. While the rose and the extended objects are there treated as also things in themselves, Saturn is taken only in its phenomenal existence. In view of the general confusion, it is a minor inconsistency that Kant should here maintain, in direct opposition to A 28-9, that secondary qualities can be attributed to the empirical object.

This passage from the second edition is a development of Prolegomena, § 13, iii. Kant there employs the term appearance in a quite indefinite manner. For the most part he seems to mean by it any and every sense-experience, whether normal or abnormal, and even to include under it dream images. But it is also employed in the second of the above meanings, as signifying those sense-perceptions which harmonise with general experience. Illusion is throughout employed in the third of the above meanings. Kant’s illustration, that of the apparently retrograde movements of the planets, necessitates a distinction between apparent and real motion in space, and consequently leads to the fruitful distinction noted above. Kant gives, however, no sign that he is conscious of the complicated problems involved.

In the interval between the Prolegomena (1783) and the second edition of the Critique (1787) Mendelssohn had published (1785) his Morgenstunden. In its introduction, entitled Vorerkenntniss von Wahrheit, Schein und Irrthum, he very carefully distinguishes between illusion (Sinnenschein) and error of judgment (Irrthum). This introduction Kant had read. In a letter to Schütz he cites it by title, and praises it as “acute, original, and of exemplary clearness.” It is therefore the more inexcusable that he should again in the second edition of the Critique have confused these two so radically different meanings of the term Schein. Mendelssohn, however, drew no distinction between Schein and Erscheinung. They were then used as practically synonymous, though of course Schein was the stronger term. Kant seems to have been the first to distinguish them sharply and to attempt to define the one in opposition to the other. But the very fact that Erscheinung and Schein were currently employed as equivalent terms, and that the distinction, though one of his own drawing, had been mentioned only in the most cursory manner in the first edition of the Critique, removes all justification for his retort upon his critics of “unpardonable misconception.” His anger was really due, not to the objection in itself, but to the implied comparison of his position to that of Berkeley. Such comparison never failed to arouse Kant’s wrath. For however much this accusation might be justified by his own frequent lapses into subjectivism of the most extreme type, even its partial truth was more than he was willing to admit. Berkeley represents in his eyes, not merely a subjectivist interpretation of the outer world, but the almost diametrical opposite of everything for which he himself stood. Discussion of Kant’s relation to Berkeley had best, however, be introduced through consideration of the passage immediately following in which Kant refers to Berkeley by name.

=III. (Second Part) B 70.=--Kant urges that his doctrine of the ideality of space and time, so far from reducing objects to mere illusion, is the sole means of defending their genuine reality. If space and time had an independent existence, they would have to be regarded as more real than the bodies which occupy them. For on this view space and time would continue to exist even if all their contents were removed; they would be antecedent necessary conditions of all other existences. But space and time thus interpreted are impossible conceptions. The reality of bodies is thereby made to depend upon Undinge. If this were the sole alternative, “the good Bishop Berkeley [could] not be blamed for degrading bodies to mere illusion.” We should, Kant maintains, have to proceed still further, denying even our own existence. For had Berkeley taken account of time as well as of space, a similar argument, consistently developed in regard to time, would have constrained him to reduce the self to the level of mere illusion. Belief in the reality of things in themselves, whether spiritual or material, is defensible only if space and time be viewed as subjective. In other words, Berkeley’s idealism is an inevitable consequence of a realist view of space. But it is also its reductio ad absurdum.

The term Schein is not employed throughout this passage in either of the two meanings of the appended note, but in that of the main text. It signifies a representation, to which no existence corresponds.

KANT’S RELATION TO BERKELEY

By idealism Kant means any and every system which maintains that the sensible world does not exist in the form in which it presents itself to us. The position is typified in Kant’s mind by the Eleatics, by Plato, and by Descartes, all of whom are rationalists. With the denial of reality to sense-appearances they combine a belief in the possibility of rationally comprehending its supersensible basis. Failing to appreciate the true nature of the sensible, they misunderstand the character of geometrical science, and falsely ascribe to pure understanding a power of intellectual intuition. Kant’s criticisms of Berkeley show very clearly that it is this more general position which he has chiefly in view. To Berkeley Kant objects that only in sense-experience is there truth, that it is sensibility, not understanding, which possesses the power of a priori intuition, and that through pure understanding, acting in independence of sensibility, no knowledge of any kind can be acquired. In other words, Kant classes Berkeley with the rationalists. And, as we have already seen, he even goes the length of regarding Berkeley’s position as the reductio ad absurdum of the realist view of space. Kant does, indeed, recognise that Berkeley differs from the other idealists, in holding an empirical view of space, and consequently of geometry, but this does not prevent Kant from maintaining that Berkeley’s thinking is influenced by certain fundamental implications of the realist position. Berkeley’s insight--such would seem to be Kant’s line of argument--is perverted by the very view which he is attacking. Berkeley appreciates only what is false in the Cartesian view of space; he is blind to the important element of truth which it contains. Empiricist though he be, he has no wider conception of the function and powers of sensibility than have the realists from whom he separates himself off; and in order to comprehend those existences to which alone he is willing to allow true reality, he has therefore, like the rationalists, to fall back upon pure reason.

That Kant’s criticism of Berkeley should be extremely external is not, therefore, surprising. He is interested in Berkeley’s positive teaching only in so far as it enables him to illustrate the evil tendencies of a mistaken idealism, which starts from a false view of the functions of sensibility and of understanding, and of the nature of space and time. The key to the true idealism lies, he claims, in the Critical problem, how a priori synthetic judgments can be possible. This is the fundamental problem of metaphysics, and until it has been formulated and answered no advance can be made.

“My so-called (Critical) idealism is thus quite peculiar in that it overthrows ordinary idealism, and that through it alone a priori cognition, even that of geometry, attains objective reality, a thing which even the keenest realist could not assert till I had proved the ideality of space and time.”

In order to make Kant’s account of Berkeley’s teaching really comprehensible, we seem compelled to assume that he had never himself actually read any of Berkeley’s own writings. Kant’s acquaintance with the English language was most imperfect, and we have no evidence that he had ever read a single English book. When he quotes Pope and Addison, he does so from German translations. Subsequent to 1781 he could, indeed, have had access to Berkeley’s Dialogues between Hylas and Philonous in a German translation; but in view of the account which he continues to give of Berkeley’s teaching, it does not seem likely that he had availed himself of this opportunity. As to what the indirect sources of Kant’s knowledge of Berkeley may have been, we cannot decide with any certainty, but amongst them must undoubtedly be reckoned Hume’s statements in regard to Berkeley in the Enquiry, and very probably also the references to Berkeley in Beattie’s Nature of Truth. From the former Kant would learn of Berkeley’s empirical view of space and also of the sceptical tendencies of his idealist teaching. From it he might also very naturally infer that Berkeley denies all reality to objects. By Beattie Kant would be confirmed in this latter view, and also in his contention that Berkeley is unable to supply a criterion for distinguishing between reality and dreams. Kant may also have received some impressions regarding Berkeley from Hamann.

To take Kant’s criticisms of Berkeley more in detail. In the first edition of the Critique Kant passes two criticisms, without, however, mentioning Berkeley by name: first, that he overlooks the problem of time, and, like Descartes, ascribes complete reality to the objects of inner sense. This is the cause of a second error, namely, that he views the objects of outer sense as mere illusion (blosser Schein). Proceeding, Kant argues that inner and outer sense are really in the same position. Though they yield only appearances, these appearances are conditioned by things in themselves. Through this relation to things in themselves they are distinguished from all merely subjective images. Berkeley is again referred to in the fourth Paralogism. His idealism is distinguished from that of Descartes. The one is dogmatic; the other is sceptical. The one denies the existence of matter; the other only doubts whether it is possible to prove it. Berkeley claims, indeed, that there are contradictions in the very conception of matter; and Kant remarks that this is an objection which he will have to deal with in the section on the Antinomies. But this promise Kant does not fulfil; and doubtless for the reason that, however unwilling he may be to make the admission, on this point his own teaching, especially in the Dialectic, frequently coincides with that of Berkeley. So little, indeed, is Kant concerned in the first edition to defend his position against the accusation of subjectivism, that in this same section he praises the sceptical idealist as a “benefactor of human reason.”

“He compels us, even in the smallest advances of ordinary experience, to keep on the watch, lest we consider as a well-earned possession what we perhaps obtain only in an illegitimate manner. We are now in a position to appreciate the value of the objections of the idealist. They drive us by main force, unless we mean to contradict ourselves in our commonest assertions, to view all our perceptions, whether we call them inner or outer, as a consciousness only of what is dependent on our sensibility. They also compel us to regard the outer objects of these perceptions not as things in themselves, but only as representations, of which, as of every other representation, we can become immediately conscious, and which are entitled outer because they depend on what we call ‘outer sense’ whose intuition is space. Space itself, however, is nothing but an inner mode of representation in which certain perceptions are connected with one another.”

These criticisms are restated in A 491-2 = B 519-20, with the further addition that in denying the existence of extended beings “the empirical idealist” removes the possibility of distinguishing between reality and dreams. This is a new criticism. Kant is no longer referring to the denial of unknowable things in themselves. He is now maintaining that only the Critical standpoint can supply an immanent criterion whereby real experiences may be distinguished from merely subjective happenings. This point is further insisted upon in the Prolegomena, but is nowhere developed with any direct reference to Berkeley’s own personal teaching. Kant assumes as established that any such criterion must rest upon the a priori; and in this connection Berkeley is conveniently made to figure as a thoroughgoing empiricist.

The Critique, on its publication, was at once attacked, especially in the Garve-Feder review, as presenting an idealism similar to that of Berkeley. As Erdmann has shown, the original plan of the Prolegomena was largely modified in order to afford opportunity for reply to this “unpardonable and almost intentional misconception.” Kant’s references to Berkeley, direct and indirect, now for the first time manifest a polemical tone, exaggerating in every possible way the difference between their points of view. Only the transcendental philosophy can establish the possibility of a priori knowledge, and so it alone can afford a criterion for distinguishing between realities and dreams. It alone will account for the possibility of geometrical science; Berkeley’s idealism would render the claims of that science wholly illusory. The Critical idealism transcends experience only so far as is required to discover the conditions which make empirical cognition possible; Berkeley’s idealism is ‘visionary’ and ‘mystical.’ Even sceptical idealism now comes in for severe handling. It may be called “dreaming idealism”; it makes things out of mere representations, and like idealism in its dogmatic form it virtually denies the existence of the only true reality, that of things in themselves. Sceptical idealism misinterprets space by making it empirical, dogmatic idealism by regarding it as an attribute of the real. Both entirely ignore the problem of time. For these reasons they underestimate the powers of sensibility (to which space and time belong as a priori forms), and exaggerate those of pure understanding.

“The position of all genuine idealists from the Eleatics to Berkeley is contained in this formula: ‘All cognition through the senses and experience is nothing but mere illusion, and only in the ideas of pure understanding and Reason is there truth.’ The fundamental principle ruling all my idealism, on the contrary, is this: ‘All cognition of things solely from pure understanding or pure Reason is nothing but mere illusion and only in experience is there truth.’”

This is an extremely inadequate statement of the Critical standpoint, but it excellently illustrates Kant’s perverse interpretation of Berkeley’s teaching.

To these criticisms Kant gives less heated but none the less explicit expression in the second edition of the Critique. He is now much more careful to avoid subjectivist modes of statement. His phenomenalist tendencies are reinforced, and come to clearer expression of all that they involve. The fourth Paralogism with its sympathetic treatment of empirical idealism is omitted, and in addition to the above passage Kant inserts a new section, entitled Refutation of Idealism, in which he states his position in a much more adequate manner.

=IV. B 71.=--Kant continues the argument of A 39. If space and time condition all existence, they will condition even divine existence, and so must render God’s omniscience, which as such must be intuitive, not discursive, difficult of conception. Upon this point Kant is more explicit in the Dissertation.

“Whatever is, is somewhere and sometime, is a spurious axiom.... By this spurious principle all beings, even though they be known intellectually, are restricted in their existence by conditions of space and time. Philosophers therefore discuss every form of idle question regarding the locations in the corporeal universe of substances that are immaterial--and of which for that very reason there can be no sensuous intuition nor any possible spatial representation--or regarding the seat of the soul, and the like. And since the sensuous mixes with the intellectual about as badly as square with round, it frequently happens that the one disputant appears as holding a sieve into which the other milks the he-goat. The presence of immaterial things in the corporeal world is virtual, not local, although it may conveniently be spoken of as local. Space contains the conditions of possible interaction only when it is between material bodies. What, however, in immaterial substances constitutes the external relations of force between them or between them and bodies, obviously eludes the human intellect.... But when men reach the conception of a highest and extra-mundane Being, words cannot describe the extent to which they are deluded by these shades that flit before the mind. They picture God as present in a place: they entangle Him in the world where He is supposed to fill all space at once. They hope to make up for the [spatial] limitation they thus impose by thinking of God’s place per eminentiam, i.e. as infinite. But to be present in different places at the same time is absolutely impossible, since different places are mutually external to one another, and consequently what is in several places is outside itself, and is therefore present to itself outside itself--which is a contradiction in terms. As to time, men have got into an inextricable maze by releasing it from the laws that govern sense knowledge, and what is more, transporting it beyond the confines of the world to the Being that dwells there, as a condition of His very existence. They thus torment their souls with absurd questions, for instance, why God did not fashion the world many centuries earlier. They persuade themselves that it is easily possible to conceive how God may discern present things, i.e. what is actual in the time in which He is. But they consider that it is difficult to comprehend how He should foresee the things about to be, i.e. the actual in the time in which He is not yet. They proceed as if the existence of the Necessary Being descended successively through all the moments of a supposed time, and having already exhausted part of His duration, foresaw the eternal life that still lies before Him together with the events which occur simultaneously [with that future life of His]. All these speculations vanish like smoke when the notion of time has been rightly discerned.”

The references in B 71-2 to the intuitive understanding are among the many signs of Kant’s increased preoccupation, during the preparation of the second edition, with the problems which it raises. Such understanding is not sensuous, but intellectual; it is not derivative, but original; the object itself is created in the act of intuition. Or, as Kant’s position may perhaps be more adequately expressed, all of God’s activities are creative, and are inseparable from the non-sensuous intuition whereby both they and their products are apprehended by Him. Kant’s reason for again raising this point may be Mendelssohn’s theological defence of the reality of space in his Morgenstunden. Mendelssohn has there argued that just as knowledge of independent reality is confirmed by the agreement of different senses, and is rendered the more certain in proportion to the number of senses which support the belief, so the validity of our spatial perceptions is confirmed in proportion as men are found to agree in this type of experience with one another, with the animals, and with angelic beings. Such inductive inference will culminate in the proof that even the Supreme Being apprehends things in this same spatial manner. Kant’s reply is that however general the intuition of space may be among finite beings, it is sensuous and derivative, and therefore must not be predicated of a Divine Being. For obvious reasons Kant has not felt called upon to point out the inadequacy of this inductive method to the solution of Critical problems. In A 42 Kant, arguing that our forms of intuition are subjective, claims that they do not necessarily belong to all beings, though they must belong to all men. He is quite consistent in now maintaining that their characteristics, as sensuous and derivative, do not necessarily preclude their being the common possession of all finite beings.

THE PARADOX OF INCONGRUOUS COUNTERPARTS

The purpose, as already noted, of the above sections II. to IV., as added in the second edition, is to afford ‘confirmation’ of the ideality of space and time. That being so, it is noticeable that Kant has omitted all reference to an argument embodied, for this same purpose, in § 13 of the Prolegomena. The matter is of sufficient importance to call for detailed consideration.

As the argument of the Prolegomena is somewhat complicated, it is advisable to approach it in the light of its history in Kant’s earlier writings. It was to his teacher Martin Knutzen that Kant owed his first introduction to Newton’s cosmology; and from Knutzen he inherited the problem of reconciling Newton’s mechanical view of nature and absolute view of space with the orthodox Leibnizian tenets. In his first published work Kant seeks to prove that the very existence of space is due to gravitational force, and that its three-dimensional character is a consequence of the specific manner in which gravity acts. Substances, he teaches, are unextended. Space results from the connection and order established between them by the balancing of their attractive and repulsive forces. And as the law of gravity is merely contingent, other modes of interaction, and therefore other forms of space, with more than three dimensions, must be recognised as possible.

“A science of all these possible kinds of space would undoubtedly be the highest enterprise which a finite understanding could undertake in the field of geometry.”

In the long interval between 1747 and 1768 Kant continued to hold to some such compromise, retaining Leibniz’s view that space is derivative and relative, and rejecting Newton’s view that it is prior to, and pre-conditions, all the bodies that exist in it. But in that latter year he published a pamphlet in which, following in the steps of the mathematician, Euler, he drew attention to certain facts which would seem quite conclusively to favour the Newtonian as against the Leibnizian interpretation of space. The three dimensions of space are primarily distinguishable by us only through the relation in which they stand to our body. By relation to the plane that is at right angles to our body we distinguish ‘above’ and ‘below’; and similarly through the other two planes we determine what is ‘right’ and ‘left,’ ‘in front’ and ‘behind.’ Through these distinctions we are enabled to define differences which cannot be expressed in any other manner. All species of hops--so Kant maintains--wind themselves around their supports from left to right, whereas all species of beans take the opposite direction. All snail shells, with some three exceptions, turn, in descending from their apex downwards, from left to right. This determinate direction of movement, natural to each species, like the difference in spatial configuration between a right and a left hand, or between a right hand and its reflection in a mirror, involves in all cases a reference of the given object to the wider space within which it falls, and ultimately to space as a whole. Only so can its determinate character be distinguished from its opposite counterpart. For as Kant points out, though the right and the left hand are counterparts, that is to say, objects which have a common definition so long as the arrangement of the parts of each is determined in respect to its central line of reference, they are none the less inwardly incongruent, since the one can never be made to occupy the space of the other. As he adds in the Prolegomena, the glove of one hand cannot be used for the other hand. This inner incongruence compels us to distinguish them as different, and this difference is only determinable by location of each in a single absolute space that constrains everything within it to conform to the conditions which it prescribes. In three-dimensional space everything must have a right and a left side, and must therefore exhibit such inner differences as those just noted. Spatial determinations are not, as Leibniz teaches, subsequent to, and dependent upon, the relations of bodies to one another; it is the former that determine the latter.

“The reason why that which in the shape of a body exclusively concerns its relation to pure space can be apprehended by us only through its relation to other bodies, is that absolute space is not an object of any outer sensation, but a fundamental conception which makes all such differences possible.”

Kant enforces his point by arguing that if the first portion of creation were a human hand, it would have to be either a right or a left hand. Also, a different act of creation would be demanded according as it was the one or the other. But if the hand alone existed, and there were no pre-existing space, there would be no inward difference in the relations of its parts, and nothing outside it to differentiate it. It would therefore be entirely indeterminate in nature, i.e. would suit either side of the body, which is impossible.

This adoption of the Newtonian view of space in 1768 was an important step forward in the development of Kant’s teaching, but could not, in view of the many metaphysical difficulties to which it leads, be permanently retained; and in the immediately following year--a year which, as he tells us, “gave great light”--he achieved the final synthesis which enabled him to combine all that he felt to be essential in the opposing views. Though space is an absolute and preconditioning source of differences which are not conceptually resolvable, it is a merely subjective form of our sensibility.

Now it is significant that when Kant expounds this view in the Dissertation of 1770, the argument from incongruous counterparts is no longer employed to establish the absolute and pre-conditioning character of space, but only to prove that it is a pure non-conceptual intuition.

“Which things in a given space lie towards one side, and which lie towards the other, cannot by any intellectual penetration be discursively described or reduced to intellectual marks. For in solids that are completely similar and equal, but incongruent, such as the right and the left hand (conceived solely in terms of their extension), or spherical triangles from two opposite hemispheres, there is a diversity which renders impossible the coincidence of their spatial boundaries. This holds true, even though they can be substituted for one another in all those respects which can be expressed in marks that are capable of being made intelligible to the mind through speech. It is therefore evident that the diversity, that is, the incongruity, can only be apprehended by some species of pure intuition.”

There is no mention of this argument in the first edition of the Critique, and when it reappears in the Prolegomena it is interpreted in the light of an additional premiss, and is made to yield a very different conclusion from that drawn in the Dissertation, and a directly opposite conclusion from that drawn in 1768. Instead of being employed to establish either the intuitive character of space or its absolute existence, it is cited as evidence in proof of its subjectivity. As in 1768, it is spoken of as strange and paradoxical, and many of the previous illustrations are used. The paradox consists in the fact that bodies and spherical figures, conceptually considered, can be absolutely identical, and yet for intuition remain diverse. This paradox, Kant now maintains in opposition to his 1768 argument, proves that such bodies and the space within which they fall are not independent existences. For were they things in themselves, they would be adequately cognisable through the pure understanding, and could not therefore conflict with its demands. Being conceptually identical, they would necessarily be congruent in every respect. But if space is merely the form of sensibility, the fact that in space the part is only possible through the whole will apply to everything in it, and so will generate a fundamental difference between conception and intuition. Things in themselves are, as such, unconditioned, and cannot, therefore, be dependent upon anything beyond themselves. The objects of intuition, in order to be possible, must be merely ideal.

Now the new premiss which differentiates this argument from that of 1768, and which brings Kant to so opposite a conclusion, is one which is entirely out of harmony with the teaching of the Critique. In this section of the Prolegomena Kant has unconsciously reverted to the dogmatic standpoint of the Dissertation, and is interpreting understanding in the illegitimate manner which he so explicitly denounces in the section on Amphiboly.

“The mistake ... lies in employing the understanding contrary to its vocation transcendentally [i.e. transcendently] and in making objects, i.e. possible intuitions, conform to concepts, not concepts to possible intuitions, on which alone their objective validity rests.”

The question why no mention of this argument is made in the second edition of the Critique is therefore answered. Kant had meantime, in the interval between 1783 and 1787, become aware of the inconsistency of the position. So far from being a paradox, this assumed conflict rests upon a false view of the function of the understanding. The relevant facts may serve to confirm the view of space as an intuition in which the whole precedes the parts; but they can afford no evidence either of its absoluteness or of its ideality. In 1768 they seem to Kant to prove its absoluteness, only because the other alternative has not yet occurred to him. In 1783 they seem to him to prove its ideality, only because he has not yet completely succeeded in emancipating his thinking from the dogmatic rationalism of the Dissertation.

As already noted, Kant’s reason for here asserting that space is intuitive in nature, namely, that in it the parts are conditioned by the whole, is also his reason for elsewhere describing it as an Idea of Reason. The further implication of the argument of the Prolegomena, that in the noumenal sphere the whole is made possible only by its unconditioned parts, raises questions the discussion of which must be deferred. The problem recurs in the Dialectic in connection with Kant’s definition of the Idea of the unconditioned. In the Ideas of Reason Kant comes to recognise the existence of concepts which do not conform to the reflective type analysed by the traditional logic, and to perceive that these Ideas can yield a deeper insight than any possible to the discursive understanding. The above rationalistic assumption must not, therefore, pass unchallenged. It may be that in the noumenal sphere all partial realities are conditioned by an unconditioned whole.

* * * * *

=Concluding Paragraph.=--The wording of this paragraph is in keeping with the increased emphasis which in the Introduction to the second edition is given to the problem, how a priori synthetic judgments are possible. Kant characteristically fails to distinguish between the problems of pure and applied mathematics, with resulting inconsecutiveness in his argumentation.

THE TRANSCENDENTAL DOCTRINE OF ELEMENTS