By an 'idea' the world in general understands what it is sometimes ready to call a mere idea. And by a mere idea is meant something which is not reality, but a peculiarity of an individual mind, or group of minds-a fancy, without objective truth:—something, we may even add, which for many people is located in their own head or brain, cut off by blank bone-walls from the open air of real being. By idea (representation, Vorstellung) Kant meant that an object is always and essentially the object of a mind: always relative to a subject consciousness, and implying it, just as a subject consciousness always implies an object.
And by 'existence outside us' the world probably means—for it is imprudent to define and refine too much in this hazy medium of words where we all drowse—existence of things on an independent footing beyond the limits of our personal, i. e. bodily and sentient, self. As regards our own trunk and limbs, most of us, except in some most strange insanity, are not likely ever to be in doubt, and are indeed more likely, after Schopenhauer's model, to take the knowledge of these personalia as the one thing immediately and intuitively certain. We talk freely enough, it is true, about existence outside our own minds; but it is only a drastic method of stating the difference between a fancy and a fact. And probably we labour under a half-unconscious hallucination that our minds are localised in some material 'seat,' somewhere in our bodily limits, and more especially in the central nerve-organs.
But, as has been said elsewhere[2], the point of view under which Mind is regarded by Kant is that of Consciousness, and especially perceptive consciousness. He describes, as we have put it above, the steps or conditions under which the single sense-observation is elevated into the rank of an experience claiming universality and necessity. But the whole machinery of consciousness—the form of sensibility and the category of intellect—is originally set in motion by an impetus from without: or at least the manipulating machinery requires a raw material on which to operate. Consciousness, or the observer who takes this point of view, feels that it is being played upon by an unknown performer—or that it is attempting to apprehend something, which, because the act of apprehension is also to some extent (and to what extent, who can say?) a transmutation, it must for ever fail to apprehend truly. It is haunted by the phantom of a real,—a thing in its own right, which can only appear in forms of sense and intellect, never in its own essential being. It is only a short step further—and Kant, if one may judge him by several isolated passages, has more than once crossed the interval,—to treat, after the manner of uneducated consciousness and of popular science, the thing in its independent being as the cause which produces the sensation, or as the original which the mental idea reproduces under the distortions or modifications rendered necessary by the sensuous-intellectual medium. For, if under the terms of one analogy the perception is an effect of the thing, under those of another it is an image or copy of external reality.
If this be Kantian philosophy—and it can quote chapter and verse in its favour—Kantian philosophy is one version of the great dogma of the relativity of knowledge. That unhappy phrase seems to have many meanings, but none of absolutely catholic acceptation. It may mean that knowledge of things states their relations—the way they behave in reference to this or that, in these or those circumstances; and that of an utterly unrelated and absolutely isolated thing, our knowledge is and must be nil. Of a thing-in-itself we can know nothing; for there is nothing to know. It may mean that knowledge is relative to the recipient or the knower,—that it is not a product which can stand by itself, but needs a vehicle and an object in close relation. In this way, too, knowledge is relative to age and circumstances: grows from period to period, and may even decay. And thirdly, the relativity of knowledge may be taken to mean that we (and all human beings) can never know the reality; because we can only know the phenomenon, i. e. the modified, transmuted, reflected thing which has reconstituted an image of itself after passing the interfering medium. For, first of all, we must strip it—this 'image' so-called (the vulgar call it the 'thing')—of the secondary qualities (sound, colour, taste, resistance) which it has in the consciousness of a being dependent on his sense-organs: and then, we must get rid also of those quantitative attributes (figure, number, size) which it has in the consciousness of a spatially and temporally perceptive being;—and then;—but the prospect is too horrible to continue further and face the Gorgon's head in the outer darkness, where man denudes appearance in the hope to meet reality.
The fact is, there are too many strands in the web which Kant is weaving, for him or perhaps for any man to keep them all well in hand and lose none of the symmetry of the pattern he designs. To be just, we must, in dealing with him as with any other philosopher, try to keep in view the unity of that design instead of insisting too minutely and too definitely upon its occasional defects. It is easy to work the pun that a 'critical' philosophy must itself expect to be criticised; it is more important to remember that by a criticism Kant meant an attempt to steer a course between the always enticing extremes of dogmatism and scepticism,—an attempt to be fair, i. e. just to both sides, and yet neither to sink into the systematised placidity of the former, nor to rove in a mere guerilla warfare with the latter. And it is the mere privateer who in the popular sense of the word is the mere critic.
Of Kant we must remember that he has the defects of his qualities. He prides himself on his distinctions of sense and intellect, of imagination and understanding, of understanding and reason; and with justice: but his distinctions are sometimes so decisive that it is hard work both for him and for his reader to reconstitute their unity. He is fond of utilising old classifications to embody his new doctrine: and occasionally the result is like what we have been taught to expect from pouring new wine into old bottles. He draws hard and fast lines, and then has to create, as it seems, supplementary links of connexion, which, if they operate, can only do so because they are the very unity he began by ignoring. One gets perfectly lost in the multitude of syntheses, in the labyrinth of categories, schemata, and principles, of paralogisms, antinomies, and ideals of pure reason. One part of this formalism may be set down to the pedantry and pipeclay of the age of the Great Frederick—pedantry, from which, as we console ourselves, our modern souls are freed. But it arises rather from the necessity of pursuing the battle between truth and error through every complicated passage in that great fortress which ages of scholasticism had—on various plans—gradually constructed. Kant is always a little of the martinet and the schoolmaster; but it is because he knows that true liberty cannot be secured without forms and must capture the old before it can plant the new. The forms as they stand in his grouping may often appear stiff and lifeless: but a more careful study, more sympathetically intent, will find that there is latent life and undisplayed connexion in the terms. Unfortunately the classified cut-and-dried specimens are more welcome to the collector, and can more easily be put in evidence in the examination-room.
Thus the original question, Are synthetic judgments a priori possible? is answered—somewhat piecemeal—in a way that leads the reader to suppose it is a question of psychology. He hears so much of sense, imagination, intellect, in the discussion, that he fancies it is an account of a process carried on by the faculties of an individual mind. And of course nobody need suppose these processes are ever carried on otherwise than by individual thinkers, human beings with proper names. But scientific investigation is concerned only with the essential and universal. For it, really, sense, imagination, &c. are not so many faculties in a thinking agent: they are grades and aspects of consciousness,—'powers' in a process of gradual mental complication (involution). Kant is really dealing with a 'normal' thought with its distinguishable constituent aspects. Only—he fails to 'make this explicit and clear. The individualism—the un-historical prepossession—of his age is upon his phraseology, if not upon his thought: and one hardly realises that he is really engaged on human thought and knowledge as a substantial subject of itself apart from its individual vehicles,—on that thought, which lives and grows in social institutions and products,—in language, science, literature, and moral usage,—the common stock which one age bequeathes to the next, but which the later-comer can only inherit if he works for and creates it afresh. If it be a psychology, therefore, it is a psychology which does not assume a soul with qualities, but which expounds the steps in the constitution of a normal intelligence.
One may note, without insisting on them too much, the defects of his treatment of the forms of thought. It may be said that, in the first place, the table of the categories was incomplete. It had been borrowed, as Kant himself tells us, from the old logical subdivision of judgments, derived more or less directly from Aristotle and the Schoolmen. Now many of the relations occurring in ordinary thought could not be reduced to any of the twelve forms, without doing violence to them. But Kant expressly disclaims exhaustiveness in detail. He could, if he would: but that is for another season. In the second place, the classification did not expressly put forward any principle or reason, and gave ground for no development. That there should be four fundamental categories, each with three divisions, making twelve in all, seems as inexplicable as that there should be four Athenian tribes in early times and twelve Phratriai. The twelve patriarchs of thought stand as if in equal authority, with little or no bearing upon one another. We have here, in short, what seems an artificial and not a natural classification of the types of thought. But Kant himself has given some explanation of the triad, and a sympathetic interpretation has shown how the four main groups are steps in the solution of one problem[3] In the third place, the question as taken up seems largely psychological, or subjective, concerning the constitution of the human mind as a percipient and cognitive faculty. But this is necessary, perhaps, to the restricted nature of Kant's problem. He is dealing with the elements that form our objective or scientific consciousness of the physical world. The deeper question of the place and work of mind in life in general, in law and morality and religion, does not at this stage come before him. That problem in fact only gradually emerges with the Criticism of the Moral Faculty and the Aesthetic Judgment. Logic—as the doctrine of the Logos which is the principle of all things, even of its own Other—had to wait for its preparation till it could be matured.
In Hegel, the question assumes a wider scope, and receives a more thorough-going answer. In the first place the question about the Categories is transferred from what we have called the epistemological or psychological, to what Hegel terms the logical, sphere. It is transferred from the Reason subjectively considered as a mere receptive and synthetic human consciousness to the Reason which is in the world and in history,—a Reason, which our Reason, as it were, touches, and so becomes possessed of knowledge. In the second place, the Categories become a vast multitude. The intellectual telescope discovers new stars behind the constellations named in ancient lore. There is no longer, if there ever was, any mystic virtue supposed to inhere in the number twelve: while the triadic arrangement is made radical and everywhere recurs. The modern chemist of thought vastly amplifies the number of its elementary types and factors, and proves that many of the old Categories are neither simple nor indecomposable. Thirdly, there is a systematic development or process which links the Categories together, and shows how the most simple, abstract, and inadequate, inevitably lead up to the most complex and adequate. Each term or member in the organism of thought has its place conditioned by all the others: each of them is the germ, or the ripe fruit of another.