Chapter XII: Part 12

Thus, on the one hand, the individualist conception, when carried out
to its full extent, leads to the total negation of all real cognition.
If the real system of things, to which conscious experience has
reference, be regarded as standing in casual relation to this
experience there is no conceivable ground for the extension to reality
of the notions which somehow are involved in thought. The same result
is apparent, on the other hand, when we consider the theory of
knowledge implied in the Leibnitzian individualism. The metaphysical
conception of the monads, each of which is the universe _in nuce_,
presents insuperable difficulties when the connexion or
interdependence of the monads is in question, and these difficulties
obtrude themselves when the attempt is made to work out a consistent
doctrine of cognition. For the whole mass of cognisable fact, the
_mundus intelligibilis_, is contained _impliciter_ in each monad, and
the several modes of apprehension can only be regarded as so many
stages in the developing consciousness of the monad. Sense and
understanding, real connexion of facts and analysis of notions, are
not, therefore, distinct in kind, but differ only in degree. The same
fundamental axioms, the logical principles of identity and sufficient
reason, are applicable in explanation of all given propositions. It is
true that Leibnitz himself did not work out any complete doctrine of
knowledge, but in the hands of his successors the theory took definite
shape in the principle that the whole work of cognition is in essence
analytical. The process of analysis might be complete or incomplete.
For finite intelligences there was an inevitable incompleteness so far
as knowledge of matters of fact was concerned. In respect to them,
the final result was found in a series of irreducible notions or
categories, the _prima possibilia_, the analysis and elucidation of
which was specifically the business of philosophy or metaphysics.

It will be observed that, in the Leibnitzian as in the empirical
individualism, the fundamental notion is still that of the abstract
separation of the thinking subject from the materials of conscious
experience. From this separation arise all the difficulties in the
effort to develop the notion systematically, and in tracing the
history of Kant's philosophical progress we are able to discern the
gradual perception on his part that here was to be found the ultimate
cause of the perplexities which became apparent in considering the
subordinate doctrines of the system. The successive essays which have
already been enumerated as composing Kant's precritical work are not
to be regarded as so many imperfect sketches of the doctrines of the
_Kritik_, nor are we to look in them for anticipations of the critical
view. They are essentially tentative, and exhibit with unusual
clearness the manner in which the difficulties of a received theory
force on a wider and more comprehensive view. There can be no doubt
that some of the special features of the _Kritik_ are to be found in
these precritical essays, e.g. the doctrine of the _Aesthetik_ is
certainly foreshadowed in the _Dissertation_ of 1770; the _Kritik_,
however, is no patchwork, and what appears in the _Dissertation_ takes
an altogether new form when it is wrought into the more comprehensive
conception of the later treatise.

The particular problem which gave the occasion to the first of the
precritical writings is, in an imperfect or particular fashion, the
fundamental question to which the _Kritik_ is an answer. What is the
nature of the distinction between knowledge gained by analysis of
notions and knowledge of matters of fact? Kant seems never to have
been satisfied with the Wolffian identification of logical axioms and
of the principle of sufficient reason. The tract on the _False
Subtlety of the Four Syllogistic Figures_, in which the view of
thought or reason as analytic is clearly expressed, closes with the
significant division of judgments into those which rest upon the
logical axioms of identity and contradiction and those for which no
logical ground can be shown. Such immediate or indemonstrable
judgments, it is said, abound in our experience. They are, in fact, as
Kant presently perceived, the foundations for all judgments regarding
real existence. It was impossible that the question regarding their
nature and legitimacy and their distinction from analytic judgments
should not present itself to him. The three tracts belonging to the
years 1763-1764 bring forward in the sharpest fashion the essential
opposition between the two classes of judgments. In the _Essay on
Negative Quantities_, the fundamental thought is the total distinction
in kind between logical opposition (the contradictoriness of notions,
which Kant always viewed as formed, definite products of thought) and
real opposition. For the one adequate explanation is found in the
logical axiom of analytical thinking; for the other no such
explanation is to be had. Logical ground and real ground are totally
distinct. "I can understand perfectly well," says Kant, "how a
consequence follows from its reason according to the law of identity,
since it is discoverable by mere analysis of the notion contained in
it.... But how something follows from another thing and not according
to the law of identity, this I should gladly have made clear to me....
How shall I comprehend that, since something is, something else should
be?" Real things, in short, are distinct existences, and, as distinct,
not necessarily or logically connected in thought. "I have," he
proceeds, "reflected on the nature of our knowledge in relation to our
judgment of reason and consequent, and I intend to expound fully the
result of my reflections. It follows from them that the relation of a
real ground to that which is thereby posited or denied cannot be
expressed by a judgment but only by means of a notion, which by
analysis may certainly be reduced to yet simpler notions of real
grounds, but yet in such a way that the final resort of all our
cognition in this regard must be found in simple and irreducible
notions of real grounds, the relation of which to their consequents
cannot be made clear."

The striking similarity between Kant's expressions in this _Essay_ and
the remarks with which Hume introduces his analysis of the notion of
cause has led to the supposition that at this period of his
philosophical career Kant was definitely under the influence of the
earlier empirical thinker. Consideration of the whole passage is quite
sufficient to show the groundlessness of this supposition. The
difficulty with which Kant is presented was one arising inevitably
from reflection upon the Leibnitzian theory of knowledge, and the
solution does not in any way go beyond that theory. It is a solution,
in fact, which must have been impossible had the purport of Hume's
empirical doctrine been present to Kant's mind. He is here at the
point at which he remained for many years, accepting without any
criticism certain fundamental notions as required for real cognition.
His ideal of metaphysic is still that of complete analysis of given
notions. No glimmering of the further question, Whence come these
notions and with what right do we apply them in cognition? is yet
apparent. Any direct influence from Hume must be referred to a later
period in his career.

The prize essay _On the Principles of Natural Theology and Morals_
brings forward the same fundamental opposition--though in a special
form. Here, for the first time, appears definitely the distinction
between synthesis and analysis, and in the distinction is found the
reason for the superior certainty and clearness of mathematics as
opposed to philosophy. Mathematics, Kant thinks, proceeds
synthetically, for in it the notions are constructed. Metaphysics, on
the other hand, is analytical in method; in it the notions are given,
and by analysis they are cleared up. It is to be observed that the
description of mathematics as synthetic is not an anticipation of the
critical doctrine on the same subject. Kant does not, in this place,
raise the question as to the reason for assuming that the arbitrary
syntheses of mathematical construction have any reference to reality.
The deeper significance of synthesis has not yet become apparent.

In the _Only Possible Ground of Proof for the Existence of God_, the
argument, though largely Leibnitzian, advances one step farther
towards the ultimate inquiry. For there Kant states as precisely as in
the critique of speculative theology his fundamental doctrine that
real existence is not a predicate to be added in thought to the
conception of a possible subject. So far as subjective thought is
concerned, possibility, not real existence, is contained in any
judgment.

The year 1765 was marked by the publication of Leibnitz's posthumous
_Nouveaux Essais_, in which his theory of knowledge is more fully
stated than in any of his previous tracts. In all probability Kant
gave some attention to this work, though no special reference to it
occurs in his writings, and it may have assisted to give additional
precision to his doctrine. In the curious essay, _Dreams of a
Clairvoyant_, published 1766, he emphasizes his previously reached
conclusion that connexions of real fact are mediated in our thought by
ultimate notions, but adds that the significance and warrant for such
notions can be furnished only by experience. He is inclined,
therefore, to regard as the function of metaphysics the complete
statement of these ultimate, indemonstrable notions, and therefore the
determination of the limits to knowledge by their means. Even at this
point, where he approximates more closely to Hume than to any other
thinker, the difficulty raised by Hume does not seem to occur to him.
He still appears to think that experience does warrant the employment
of such notions, and when there is taken into account his
correspondence with Lambert during the next few years, one would be
inclined to say that the _Architektonik_ of the latter represents most
completely Kant's idea of philosophy.

On another side Kant had been shaking himself free from the principles
of the Leibnitzian philosophy. According to Leibnitz, space, the order
of coexisting things, resulted from the relations of monads to one
another. But Kant began to see that such a conception did not accord
with the manner in which we determine directions or positions in
space. In the curious little essay, _On the Ground of distinguishing
Particular Divisions in Space_, he pointed out that the idea of space
as a whole is not deducible from the experience of particular spaces,
or particular relations of objects in space, that we only cognize
relations in space by reference to space as a whole, and finally that
definite positions involve reference to space as a given whole.

The whole development of Kant's thought up to this point is
intelligible when regarded from the Leibnitzian point of view, with
which he started. There appears no reason to conclude that Hume at
this time exercised any direct influence. One may go still further,
and add that even in the _Dissertation_ of 1770, generally regarded as
more than foreshadowing the _Kritik_, the really critical question is
not involved. A brief notice of the contents of this tract will
suffice to show how far removed Kant yet was from the methods and
principles of the critical or transcendental philosophy. Sense and
understanding, according to the _Dissertation_, are the two sources of
knowledge. The objects of the one are things of sense or _phenomena_;
the objects of the other are _noumena_. These are absolutely distinct,
and are not to be regarded as differing only in degree. In _phenomena_
we distinguish _matter_, which is given by sense, and _form_, which is
the law of the order of sensations. Such form is twofold--the order of
space and time. Sensations formed by space and time compose the world
of appearance, and this when treated by the understanding, according
to logical rules, is _experience_. But the logical use of the
understanding is not its only use. Much more important is the _real_
use, by which are produced the pure notions whereby we think things as
they are. These pure notions are the laws of the operation of the
intellect; they are _leges intellectus_.

Apart, then, from the expanded treatment of space and time as
subjective forms, we find in the _Dissertation_ little more than the
very precise and definite formulation of the slowly growing opposition
to the Leibnitzian doctrines. That the pure intellectual notions
should be defended as springing from the nature of intellect is not
out of harmony with the statement of the _Traume eines Geistersehers_,
for there the pure notions were allowed to exist, but were not held to
have validity for actual things except on grounds of experience. Here
they are supposed to exist, dissevered from experience, and are
allowed validity as determinations of things in themselves.

The stage which Kant had now reached in his philosophical development
was one of great significance. The doctrine of knowledge expressed in
the _Dissertation_ was the final form which the Wolffian rationalism
could assume for him, and, though many of the elements of the _Kritik_
are contained therein, it was not really in advance of the Wolffian
theory. The doctrine of space and time as forms of sense-perception,
the reference of both space and time and the pure intellectual notions
to the laws of the activity of mind itself, the distinction between
sense and understanding as one of kind, not of degree, with the
correlative distinction between phenomena and noumena,--all of these
reappear, though changed and modified, in the _Kritik_. But, despite
this resemblance, it seems clear that, so far as the _Dissertation_ is
concerned, the way had only been prepared for the true critical
inquiry, and that the real import of Hume's sceptical problem had not
yet dawned upon Kant. From the manner, however, in which the doctrine
of knowledge had been stated in the _Dissertation_, the further
inquiry had been rendered inevitable. It had become quite impossible
for Kant to remain longer satisfied with the ambiguous position
assigned to a fundamental element of his doctrine of knowledge, the
so-called pure intellectual notions. Those notions, according to the
_Dissertation_, had no function save in relation to
things-in-themselves, i.e. to objects which are not directly or
immediately brought into relation to our faculty of cognition. They
did not serve as the connecting links of formed experience; on the
contrary, they were supposed to be absolutely dissevered from all
experience which was possible for intelligence like ours. In his
previous essays, Kant, while likewise maintaining that such pure,
irreducible notions existed, had asserted in general terms that they
applied to experience, and that their applicability or justification
rested on experience itself, but had not raised the question as to the
ground of such justification. Now, from another side, the supreme
difficulty was presented--how could such notions have application to
any objects whatsoever? For some time the correlative difficulty, how
_objects_ of sense-perception were possible, does not seem to have
suggested itself to Kant. In the _Dissertation_ sense-perception had
been taken as receptivity of representations of objects, and
experience as the product of the treatment of such representations by
the logical or analytical processes of understanding. Some traces of
this confused fashion of regarding sense-perceptions are left even in
the _Kritik_, specially perhaps in the _Aesthetik_, and they give rise
to much of the ambiguity which unfortunately attaches to the more
developed theory of cognition. So soon, however, as the critical
question was put, On what rests the reference of representations in us
to the object or thing? in other words, How do we come to have
knowledge of objects at all? it became apparent that the problem was
one of perfect generality, and applied, not only to cognition through
the pure notions, but to sense-perceptions likewise. It is in the
statement of this general problem that we find the new and
characteristic feature of Kant's work.

There is thus no reason to doubt the substantial accuracy of Kant's
reference to the particular occasion or cause of the critical inquiry.
Up to the stage indicated by the _Dissertation_ he had been
attempting, in various ways, to unite two radically divergent modes of
explaining cognition--that which would account for the content of
experience by reference to affection from things without us, and that
which viewed the intellect itself as somehow furnished with the means
of pure, rational cognition. He now discovered that Hume's sceptical
analysis of the notion of cause was really the treatment of one
typical or crucial instance of the much more general problem. If
experience, says Hume, consists solely of states of mind somehow given
to us, each of which exists as an effect, and therefore as distinct
from others, with what right do we make the common assumption that
parts of experience are necessarily connected? The only possible
answer, drawn from the premises laid down, must be that there is no
warrant for such an assumption. Necessity for thought, as Kant had
been willing to admit and as Hume also held, involves or implies
something more than is given in experience--for that which is given is
contingent--and rests upon an a priori or pure notion. But a priori
notions, did they exist, could have no claim to regulate experience.
Hume, therefore, for his part, rejected entirely the notion of cause
as being fictitious and delusive, and professed to account for the
habit of regarding experience as necessarily connected by reference to
arbitrarily formed custom of thinking. Experience, as given,
contingent material, had a certain uniformity, and recurring
uniformities generated in us the habit of regarding things as
necessarily connected. That such a resort to experience for
explanation could lead to no valid conclusion has been already noted
as evident to Hume himself.

The dogmatic or individualist conception of experience had thus proved
itself inadequate to the solution of Hume's difficulty regarding the
notion of cause,--a difficulty which Kant, erroneously, had thought to
be the only case contemplated by his predecessor. The perception of
its inadequacy in this respect, and the consequent generalization of
Hume's problem, are the essential features of the new critical method.
For Kant was now prepared to formulate his general inquiry in a
definite fashion. His long-continued reflection on the Wolffian
doctrine of knowledge had made clear to him that synthetic connexion,
the essence of real cognition, was not contained in the products of
thinking as a formal activity of mind operating on material otherwise
supplied. On the other hand, Hume's analysis enabled him to see that
synthetic connexion was not contained in experience regarded as given
material. Thus neither the formal nor the material aspect of conscious
experience, when regarded from the individualist point of view,
supplied any foundation for real knowledge, whether a priori or
empirical. An absolutely new conception of experience was necessary,
if the fact of cognition was to be explained at all, and the various
modes in which Kant expresses the business of his critical philosophy
were merely different fashions of stating the one ultimate problem,
differing according to the particular aspect of knowledge which he
happened to have in view. To inquire how synthetic a priori judgments
are possible, or how far cognition extends, or what worth attaches to
metaphysical propositions, is simply to ask, in a specific form, what
elements are necessarily involved in experience of which the subject
is conscious. How is it possible for the individual thinking subject
to connect together the parts of his experience in the mode we call
cognition?

The problem of the critical philosophy is, therefore, the complete
analysis of experience from the point of view of the conditions under
which such experience is possible for the conscious subject. The
central ideas are thus self-consciousness, as the supreme condition
under which experience is subjectively possible, and the manifold
details of experience as a varied and complex whole. The solution of
the problem demanded the utmost care in keeping the due balance
between these ideas; and it can hardly be said that Kant was perfectly
successful. He is frequently untrue to the more comprehensive
conception which dominates his work as a whole. The influence of his
previous philosophical training, nay, even the unconscious influence
of terminology, frequently induces in his statements a certain laxity
and want of clearness. He selects definitely for his starting point
neither the idea of self-consciousness nor the details of experience,
but in his actual procedure passes from one to the other, rarely, if
ever, taking into full consideration the weighty question of their
relation to one another. Above all, he is continuously under the
influence of the individualist notion which he had done so much to
explode. The conception of conscious experience, which is the net
result of the _Kritik_, is indefinitely profounder and richer than
that which had ruled the 18th century philosophizing, but for Kant
such experience still appears as somehow the arbitrary product of the
relation between the individual conscious subject and the realm of
real facts. When he is actually analysing the conditions of knowledge,
the influence of the individualist conception is not prominent; the
conditions are stated as quite general, as conditions of knowledge.
But so soon as the deeper, metaphysical problems present themselves,
the shadow of the old doctrine reappears. Knowledge is regarded as a
mechanical product, part furnished by the subject, part given to the
subject, and is thus viewed as mechanically divisible into a priori
and a posteriori, into pure and empirical, necessary and contingent.
The individual as an agent, conscious of universal moral law, is yet
regarded as in a measure opposed to experience, and the Kantian
ethical code remains purely formal. The ultimate relation between
intelligence and natural fact, expressed in the notion of end, is
thought as problematic or contingent. The difficulties or obscurities
of the Kantian system, of which the above are merely the more
prominent, may all be traced to the one source, the false or at least
inadequate idea of the individual. The more thorough explanation of
the relation between experience as critically conceived and the
individual subject was the problem left by Kant for his successors.

In any detailed exposition of the critical system it would be
requisite in the first place to state with some fullness the precise
nature of the problems immediately before Kant, and in the second
place to follow with some closeness the successive stages of the
system as presented in the three main works, the _Kritik of Pure
Reason_, the _Kritik of Practical Reason_ and the _Kritik of
Judgment_, with the more important of the minor works, the _Metaphysic
of Nature_ and the _Metaphysic of Ethics_. It would be necessary,
also, in any such expanded treatment, to bring out clearly the Kantian
classification of the philosophical sciences, and to indicate the
relation between the critical or transcendental investigation of the
several faculties and the more developed sciences to which that
investigation serves as introduction. As any detailed statement of the
critical system, however compressed, would be beyond the limits of the
present article, it is proposed here to select only the more salient
doctrines, and to point out in connexion with them what advance had
been effected by Kant, and what remained for subsequent efforts at
complete solution of the problems raised by him. Much that is of
interest and value must necessarily be omitted in any sketch of so
elaborate a system, and for all points of special interpretation
reference must needs be made to the many elaborate dissertations on or
about the Kantian philosophy.

The doctrine from which Kant starts in his critical or transcendental
investigation of knowledge is that to which the slow development of
his thought had led him. The essence of cognition or knowledge was a
synthetic act, an act of combining in thought the detached elements of
experience. Now synthesis was explicable neither by reference to pure
thought, the logical or elaborative faculty, which in Kant's view
remained analytic in function, nor by reference to the effects of
external real things upon our faculties of cognition. For, on the one
hand, analysis or logical treatment applied only to objects of
knowledge as already given in synthetic forms, and, on the other hand,
real things could yield only isolated effects and not the combination
of these effects in the forms of cognitive experience. If experience
is to be matter of knowledge for the conscious subject, it must be
regarded as the conjoint product of given material and synthetic
combination. Form and matter may indeed be regarded separably and
dealt with in isolation for purposes of critical inquiry, but in
experience they are necessarily and inseparably united. The problem of
the _Kritik_ thus becomes for Kant the complete statement of the
elements necessarily involved in synthesis, and of the subjective
processes by which these elements are realized in our individual
consciousness. He is not asking, with Locke, whence the details of
experience arise; he is not attempting a natural history of the growth
of experience in the individual mind; but he is endeavouring to state
exhaustively what conditions are necessarily involved in any fact of
knowledge, i.e. in any synthetic combination of parts of experience by
the conscious subject.

So far as the elements necessarily involved in conscious experience
are concerned, these may be enumerated briefly thus:--given data of
sense, inner or outer; the forms of perception, i.e. space and time;
the forms of thought, i.e. the categories; the ultimate condition of
knowledge, the identity of the pure ego or self. The ego or self is
the central unity in reference to which alone is any part of
experience cognizable. But the consciousness of self is the foundation
of knowledge only when related to given material. The ego has not in
itself the element of difference, and the essence of knowledge is the
consciousness of unity in difference. For knowledge, therefore, it is
necessary that difference should be _given_ to the ego. The modes
under which it is possible for such given difference to become portion
of the conscious experience of the ego, the modes under which the
isolated data can be synthetically combined so as to form a cognizable
whole, make up the form of cognition, and upon this form rests the
possibility of any a priori or rational knowledge.

The notion of the ego as a purely logical unity, containing in itself
no element of difference, and having only analytical identity, is
fundamental in the critical system, and lies at the root of all its
difficulties and perplexities. To say that the ego as an individual
does not _produce_ the world of experience is by no means the same as
to say that the ego is pure unity without element of difference. In
the one case we are treating the ego as one of the objects of
experience and denying of it productive efficacy; in the second case
we are dealing with the unity of the ego as a condition of knowledge,
of any experience whatsoever. In this second sense, it is wholly wrong
to assert that the ego is pure identity, pure unity. The unity and
identity of the ego, so regarded, are taken in abstraction, i.e. as
dissevered from the more complex whole of which they are necessary
elements. When the ego is taken as a condition of knowledge, its unity
is not more important than the difference necessarily correlated with
it. That the ego as a thing should not produce difference is quite
beside the mark. The consequences of the abstract separation which
Kant so draws between the ego and the world of experience are apparent
throughout his whole system. Assuming at the outset an opposition
between the two, self and matter of knowledge, he is driven by the
exigencies of the problem of reconciliation to insert term after term
as means of bringing them together, but never succeeds in attaining a
junction which is more than mechanical. To the end, the ego remains,
partly the pure logical ego, partly the concrete individual spirit,
and no explanation is afforded of the relation between them. It is for
this reason that the system of forms of perception and categories
appears so contingent and haphazard. No attempt is made to show how or
why the difference supplied for the pure logical ego should present
itself necessarily under these forms. They are regarded rather as
portions of the subjective mechanism of the individual consciousness.
The mind or self appears as though it were endowed with a complex
machinery by which alone it could act upon the material supplied to
it. Such a crude conception is far, indeed, from doing justice to
Kant's view, but it undoubtedly represents the underlying assumption
of many of his cardinal doctrines. The philosophy of Fichte is
historically interesting as that in which the deficiencies of Kant's
fundamental position were first discerned and the attempt made to
remedy them.

Unfortunately for the consistency of the _Kritik_, Kant does not
attempt to work out systematically the elements involved in knowledge
before considering the subjective processes by which knowledge is
realized in consciousness. He mixes up the two inquiries, and in the
general division of his work depends rather upon the results of
previous psychology than upon the lines prescribed by his own new
conception of experience. He treats the elements of cognition
separately in connexion with the several subjective processes involved
in knowledge, viz. sense and understanding. Great ambiguity is the
natural result of this procedure. For it was not possible for Kant to
avoid the misleading connotation of the terms employed by him. In
strictness, sense, understanding, imagination and reason ought to have
had their functions defined in close relation to the elements of
knowledge with which they are severally connected, and as these
elements have no existence as separate facts, but only as factors in
the complex organic whole, it might have been possible to avoid the
error of supposing that each subjective process furnished a distinct,
separately cognizable portion of a mechanical whole. But the use of
separate terms, such as sense and understanding, almost unavoidably
led to phraseology only interpretable as signifying that each
furnished a specific kind of knowledge, and all Kant's previous
training contributed to strengthen this erroneous view. Especially
noteworthy is this in the case of the categories. Kant insists upon
treating these as _Begriffe_, notions, and assigns to them certain
characteristics of notions. But it is readily seen, and in the _Logik_
Kant shows himself fully aware of the fact, that these pure connective
links of experience, general aspects of objects of intelligible
experience, do not resemble concepts formed by the so-called logical
or elaborative processes from representations of completed objects.
Nothing but harm can follow from any attempt to identify two products
which differ so entirely. So, again, the _Aesthetik_ is rendered
extremely obscure and difficult by the prevalence of the view, already
noted as obtaining in the _Dissertation_, that sense is a faculty
receiving representations of objects. Kant was anxious to avoid the
error of Leibnitz, who had taken sense and understanding to differ in
degree only, not in kind; but in avoiding the one error he fell into
another of no less importance.

The consideration of the several elements which in combination make up
the fact of cognition, or perception, as it may be called, contains
little or nothing bearing on the origin and nature of the given data
of sense, inner or outer. The manifold of sense, which plays so
important a part in the critical theory of knowledge, is left in an
obscure and perplexed position. So much is clear, however, that
according to Kant sense is not to be regarded as receptive of
representations of objects. The data of sense are mere _stimuli_, not
partial or confused representations. The sense-manifold is not to be
conceived as having, _per se_, any of the qualities of objects as
actually cognized; its parts are not cognizable _per se_, nor can it
with propriety be said to be received successively or simultaneously.
When we apply predicates to the sense-manifold regarded in isolation,
we make that which is only a factor in the experience of objects into
a separate, independent object, and use our predicates transcendently.
Kant is not always in his language faithful to his view of the
sense-manifold, but the theory as a whole, together with his own
express definitions, is unmistakable. On the origin of the data of
sense, Kant's remarks are few and little satisfactory. He very
commonly employs the term _affection_ of the faculty of sense as
expressing the mode of origin, but offers no further explanation of a
term which has significance only when interpreted after a somewhat
mechanical fashion. Unquestionably certain of his remarks indicate the
view that the origin is to be sought in things-in-themselves, but
against hasty misinterpretations of such remarks there are certain
cautions to be borne in mind. The relation between phenomena and
noumena in the Kantian system does not in the least resemble that
which plays so important a part in modern psychology--between the
subjective results of sense affection and the character of the
objective conditions of such affection. Kant has pointedly declared
that it would be a gross absurdity to suppose that in his view
separate, distinct things-in-themselves existed corresponding to the
several objects of perception. And, finally, it is not at all
difficult to understand why Kant should say that the affection of
sense originated in the action of things-in-themselves, when we
consider what was the thing-in-itself to which he was referring. The
thing-in-itself to which the empirical order and relations of
sense-experience are referred is the divine order, which is not matter
of knowledge, but involved in our practical or moral beliefs. Critics
who limit their view to the _Kritik of Pure Reason_, and there, in all
probability, to the first or constructive portion of the work, must
necessarily fail to interpret the doctrines of the Kantian system,
which do not become clear or definite till the system has been
developed. Reason was, for Kant, an organic whole; the speculative and
moral aspects are never severed; and the solution of problems which
appear at first sight to belong solely to the region of speculative
thought may be found ultimately to depend upon certain characteristics
of our nature as practical.

Data of sense-affection do not contain in themselves synthetic
combination. The first conditions of such combination are found by
Kant in the universal forms under which alone sense-phenomena manifest
themselves in experience. These universal forms of perception, space
and time, are necessary, a priori, and in characteristic features
resembling intuitions, not notions. They occupy, therefore, a peculiar
position, and one section of the _Kritik_, the _Aesthetik_, is
entirely devoted to the consideration of them. It is important to
observe that it is only through the a priori character of these
perceptive forms that rational science of nature is at all possible.
Kant is here able to resume, with fresh insight, his previous
discussions regarding the synthetic character of mathematical
propositions. In his early essays he had rightly drawn the distinction
between mathematical demonstration and philosophic proof, referring
the certainty of the first to the fact that the constructions were
synthetic in character and entirely determined by the action of
constructive imagination. It had not then occurred to him to ask, With
what right do we assume that the conclusions arrived at from arbitrary
constructions in mathematical matter have applicability to objects of
experience? Might not mathematics be a purely imaginary science? To
this question he is now enabled to return an answer. Space and time,
the two essential conditions of sense-perception, are not data given
by things, but universal forms of intellect into which all data of
sense must be received. Hence, whatever is true of space and time
regarded by imagination as objects, i.e. quantitative constructions,
must be true of the objects making up our sense-experience. The same
forms and the same constructive activity of imagination are involved
in mathematical synthesis and in the constitution of objects of
sense-experience. The foundation for pure or rational mathematics,
there being included under this the pure science of movement, is thus
laid in the critical doctrine of space and time.

The _Aesthetik_ isolates sense-perception, and considers its forms as
though it were an independent, complete faculty. A certain confusion,
arising from this, is noticeable in the _Analytik_ when the necessity
for justifying the position of the categories is under discussion, but
the real difficulty in which Kant was involved by his doctrine of
space and time has its roots even deeper than the erroneous isolation
of sensibility. He has not in any way "deduced" space and time, but,
proceeding from the ordinary current view of sense-experience, has
found these remaining as residuum after analysis. The relation in
which they stand to the categories or pure notions is ambiguous; and,
when Kant has to consider the fashion in which category and data of
sense are to be brought together, he merely places side by side as a
priori elements the pure connective notions and the pure forms of
perception, and finds it, apparently, only a matter of contingent
convenience that they should harmonize with one another and so render
cognition possible. To this point also Fichte was the first to call
attention.

Affection of sense, even when received into the pure forms of
perception, is not matter of knowledge. For cognition there is
requisite synthetic combination, and the intellectual function through
which such combination takes place. The forms of intellectual function
Kant proceeds to enumerate with the aid of the commonly received
logical doctrines. For this reference to logic he has been severely
blamed, but the precise nature of the debt due to the commonly
accepted logical classification is very generally misconceived.
Synthetic combination, Kant points out, is formally expressed in a
judgment, which is the act of uniting representations. At the
foundation of the judgments which express the types of synthetic
combination, through which knowledge is possible, lie the pure general
notions, the abstract aspect of the conditions under which objects are
cognizable in experience. General logic has also to deal with the
union of representations, though its unity is analytic merely, not
synthetic. But the same intellectual function which serves to give
unity in the analytic judgments of formal logic serves to give unity
to the synthetic combinations of real perception. It appeared evident,
then, to Kant that in the forms of judgment, as they are stated in the
common logic, there must be found the analogues of the types of
judgment which are involved in transcendental logic, or in the theory
of real cognition. His view of the ordinary logic was wide and
comprehensive, though in his restriction of the science to pure form
one can trace the influence of his earlier training, and it is no
small part of the value of the critical philosophy that it has revived
the study of logic and prepared the way for a more thorough
consideration of logical doctrines. The position assigned to logic by
Kant is not, in all probability, one which can be defended; indeed, it
is hard to see how Kant himself, in consistency with the critical
doctrine of knowledge, could have retained many of the older logical
theorems, but the precision with which the position was stated, and
the sharpness with which logic was marked off from cognate philosophic
disciplines, prepared the way for the more thoughtful treatment of the
whole question.

Formal logic thus yields to Kant the list of the general notions, pure
intellectual predicates, or categories, through which alone experience
is possible for a conscious subject. It has already been noted how
serious was the error involved in the description of these as notions,
without further attempt to clear up their precise significance. Kant,
indeed, was mainly influenced by his strong opposition to the
Leibnitzian rationalism, and therefore assigns the categories to
understanding, the logical faculty, without consideration of the
question,--which might have been suggested by the previous statements
of the _Dissertation_,--what relation these categories held to the
empirical notions formed by comparison, abstraction and generalization
when directed upon representations of objects. But when the categories
are described as notions, i.e. formed products of thought, there rises
of necessity the problem which had presented itself to Kant at every
stage of his precritical thinking,--with what right can we assume that
these notions apply to objects of experience? The answer which he
proceeds to give altogether explodes the definition of the categories
as formed products of thought, and enables us to see more clearly the
nature of the new conception of experience which lies in the
background of all the critical work.

The unity of the ego, which has been already noted as an element
entering into the synthesis of cognition, is a unity of a quite
distinct and peculiar kind. That the ego to which different parts of
experience are presented must be the same ego, if there is to be
cognition at all, is analytically evident; but the peculiarity is that
the ego must be conscious of its own unity and identity, and this
unity of self-consciousness is only possible in relation to difference
not contained in the ego but given to it. The unity of apperception,
then, as Kant calls it, is only possible in relation to synthetic
unity of experience itself, and the forms of this synthetic unity, the
categories, are, therefore, on the one hand, necessary as forms in
which self-consciousness is realized, and, on the other hand,
restricted in their application and validity to the data of given
sense, or the particular element of experience. Thus experience
presents itself as the organic combination of the particular of sense
with the individual unity of the ego through the universal forms of
the categories. Reference of representations to the unity of the
object, synthetic unity of apperception, and subsumption of data of
sense under the categories, are thus three sides or aspects of the one
fundamental fact.

In this deduction of the categories, as Kant calls it, there appears
for the first time an endeavour to connect together into one organic
whole the several elements entering into experience. It is evident,
however, that much was wanting before this essential task could be
regarded as complete. Kant has certainly brought together
self-consciousness, the system of the categories and data of sense. He
has shown that the conditions of self-consciousness are the conditions
of possible experience. But he has not shown, nor did he attempt to
show, how it was that the conditions of self-consciousness are the
very categories arrived at by consideration of the system of logical
judgments. He does endeavour to show, but with small success, how the
junction of category and data of sense is brought about, for according
to his scheme these stood, to a certain extent at least, apart from
and independent of one another. The failure to effect an organic
combination of the several elements was the natural consequence of the
false start which had been made.

The mode in which Kant endeavours to show how the several portions of
cognition are subjectively realized brings into the clearest light the
inconsistencies and imperfections of his doctrine. Sense had been
assumed as furnishing the particular of knowledge, understanding as
furnishing the universal; and it had been expressly declared that the
particular was cognizable only in and through the universal. Still,
each was conceived as somehow in itself complete and finished. Sense
and understanding had distinct functions, and there was wanting some
common term, some intermediary which should bring them into
conjunction. Data of sense as purely particular could have nothing in
common with the categories as purely universal. But data of sense had
at least one universal aspect,--their aspect as the particular of the
general forms, space and time. Categories were in themselves abstract
and valueless, serviceable only when restricted to possible objects of
experience. There was thus a common ground on which category and
intuition were united in one, and an intermediate process whereby the
universal of the category might be so far individualized as to
comprehend the particular of sense. This intermediate process--which
is really the junction of understanding and sense--Kant calls
productive imagination, and it is only through productive imagination
that knowledge or experience is actually realized in our subjective
consciousness. The specific forms of productive imagination are called
_schemata_, and upon the nature of the schema Kant gives much that has
proved of extreme value for subsequent thought.

Productive imagination is thus the concrete element of knowledge, and
its general modes are the abstract expression of the a priori laws of
all possible experience. The categories are restricted in their
applicability to the schema, i.e. to the pure forms of conjunction of
the manifold in time, and in the modes of combination of schemata and
categories we have the foundation for the rational sciences of
mathematics and physics. Perception or real cognition is thus
conceived as a complex fact, involving data of sense and pure
perceptive forms, determined by the category and realized through
productive imagination in the schema. The system of principles which
may be deduced from the consideration of the mode in which
understanding and sense are united by productive imagination is the
positive result of the critical theory of knowledge, and some of its
features are remarkable enough to deserve attention. According to his
usual plan, Kant arranges these principles in conformity with the
table of the categories, dividing the four classes, however, into two
main groups, the mathematical and the dynamical. The mathematical
principles are the abstract expression of the necessary mode in which
data of sense are determined by the category in the form of intuitions
or representations of objects; the dynamical are the abstract
expression of the modes in which the existence of objects of intuition
is determined. The mathematical principles are constitutive, i.e.
express determinations of the objects themselves; the dynamical are
regulative, i.e. express the conditions under which objects can form
parts of real experience. Under the mathematical principles come the
general rules which furnish the ground for the application of
quantitative reasoning to real facts of experience. For as data of
sense are only possible objects when received in the forms of space
and time, and as space and time are only cognized when determined in
definite fashion by the understanding through the schema of number
(quantity) or degree (quality), all intuitions are extensive
quantities and contain a real element, that of sense, which has
degree. Under the dynamical principles, the general modes in which the
existence of objects are determined, fall the analogies of experience,
or general rules according to which the existence of objects in
relation to one another can be determined, and the postulates of
experience, the general rules according to which the existence of
objects for us or our own subjective existence can be determined. The
analogies of experience rest upon the order of perceptions in time,
i.e. their permanence, succession or coexistence, and the principles
are respectively those of substance, causality and reciprocity. It is
to be observed that Kant in the expression of these analogies reaches
the final solution of the difficulty which had so long pressed upon
him, the difficulty as to the relation of the pure connective notions
to experience. These notions are not directly applicable to
experience, nor do we find in experience anything corresponding to the
pure intellectual notions of substance, cause and reciprocity. But
experience is for us the combination of data of sense in the forms of
productive imagination, forms determined by the pure intellectual
notions, and accordingly experience is possible for us only as in
modes corresponding to the notions. The permanent in time is substance
in any possible experience, and no experience is possible save through
the determination of all changes as in relation to a permanent in
time. Determined sequence is the causal relation in any possible
experience, and no experience is possible save through the
determination of perceived changes as in relation to a determined
order in time. So with coexistence and reciprocity.

The postulates of experience are general expressions of the
significance of existence in the experience of a conscious subject.
The element of reality in such experience must always be given by
intuition, and, so far as determination of existence is assumed,
external intuition is a necessary condition of inner intuition. The
existence of external things is as certain as the existence of the
concrete subject, and the subject cannot cognise himself as existing
save in relation to the world of facts of external perception. Inner
and outer reality are strictly correlative elements in the experience
of the conscious subject.

Throughout the positive portion of his theory of cognition, Kant has
been beset by the doctrine that the categories, as finished, complete
notions, have an import or significance transcending the bounds of
possible experience. Morever, the manner in which space and time had
been treated made it possible for him to regard these as contingent
forms, necessary for intelligences like ours, but not to be viewed as
absolutely necessary. The real meaning of these peculiarities is
hardly ever expressed by him, though it is clear that the solution of
the matter is to be found in the inadequacy of the positive theory to
meet the demands of reason for completed explanation. But the
conclusion to which he was led was one of the greatest importance for
the after development of his system. Cognition is necessarily limited.
The categories are restricted in their application to elements of
possible experience to that which is presented in intuition, and all
intuition is for the ego contingent. But to assert that cognition is
limited and its matter contingent is to form the idea of an
intelligence for whom cognition would not be limited and for whom the
data of intuition would not be given, contingent facts, but
necessarily produced along with the pure categories. This idea of an
intuitive understanding is the definite expression for the complete
explanation which reason demands, and it involves the conception of a
realm of objects for such an understanding, a realm of objects which,
in opposition to the _phenomena_ of our relative and limited
experience, may be called _noumena_ or things-in-themselves. The
_noumenon_, therefore, is in one way the object of a non-sensuous
intuition, but more correctly is the expression of the limited and
partial character of our knowledge. The idea of a noumenon is thus a
limiting notion.

Assuredly, the difficult section of the _Kritik_, on the ground of the
distinction between phenomena and noumena, would not have led to so
much misconception as it has done, had Kant then brought forward what
lies at the root of the distinction, his doctrine of reason and its
functions. Understanding, as has been seen, is the faculty of
cognition strictly so called; and within its realm, that of space,
time and matter, positive knowledge is attainable. But the ultimate
conception of understanding, that of the world of objects,
quantitatively determined, and standing in relation of mutual
reciprocity to one another, is not a final ground of explanation. We
are still able and necessitated to reflect upon the whole world of
phenomena as thus cognized, and driven to inquire after its
significance. In our reflection we necessarily treat the objects, not
as phenomena, as matters of positive, scientific knowledge, but as
things-in-themselves, as noumena. The distinction between phenomena
and noumena is, therefore, nothing but the expression of the
distinction between understanding and reason, a distinction which,
according to Kant, is merely subjective.

The specific function of reason is the effort after completed
explanation of the experience presented in cognition. But in such
effort there are no notions to be employed other than the categories,
and these, as has already been seen, have validity only in reference
to objects of possible experience. We may expect, then, to find the
transcendent employment of the categories leading into various
difficulties and inconsistencies. The criticism of reason in its
specific aspect throws fresh light on the limits to human knowledge
and the significance of experience.

Experience has presented itself as the complex result of relation
between the ego or subject and the world of phenomena. Reason may
therefore attempt a completed explanation either of the ego or of the
world of phenomena or of the total relation between them. The three
inquiries correspond to the subjects of the three ancient metaphysical
sciences, rational psychology, rational cosmology, rational theology.
It is readily seen, in regard to the first of them, that all attempts
to determine the nature of the ego as a simple, perdurable, immaterial
substance rest upon a confusion between the ego as pure logical unity
and the ego as object of intuition, and involve a transcendent use of
the categories of experience. It profits not to apply such categories
to the soul, for no intuition corresponding to them is or can be
given. The idea of the soul must be regarded as transcendent. So too
when we endeavour, with the help of the categories of quantity,
quality, relation and modality, to determine the nature and relation
of parts of the world, we find that reason is landed in a peculiar
difficulty. Any solution that can be given is too narrow for the
demands of reason and too wide for the restrictions of understanding.
The transcendent employment of the categories leads to antinomy, or
equally balanced statements of apparently contradictory results. Due
attention to the relation between understanding and reason enables us
to solve the antinomies and to discover their precise origin and
significance. Finally, the endeavour to find in the conception of God,
as the supreme reality, the explanation of experience, is seen to lead
to no valid conclusion. There is not any intuition given whereby we
might show the reality of our idea of a Supreme Being. So far as
knowledge is concerned, God remains a transcendental ideal.