been shown, be conceded to it. Time is nothing but
the form of our own internal intuition 1 .
Take away the peculiar condition of our sensi-
bility, and the idea of time vanishes, because it is
not inherent in the objects, but in the subject [p. 38.]
only that perceives them.
The reason why this objection is raised so unani-
mously, and even by those who have nothing very
tangible to say against the doctrine of the ideality
of space, is this. They could never hope to prove
apodictically the absolute reality of space, because
they are confronted by idealism, which has shown
that the reality of external objects does not admit
of strict proof, while the reality of the object of
our internal perception (the perception of my own
self and of my own status) is clear immediately
through our consciousness. The former might be
merely phenomenal, but the latter, according to their
opinion, is undeniably something real. They did
not see that both, without denying to them their
reality as representations, belong neverth less to the
phenomenon only, which must always have two
sides, the one when the object is considered by itself
(without regard to the manner in which it is per-
ceived, its quality therefore remaining always pro-
1 I can say indeed that my representations follow one another,
but this means no more than that we are conscious of them as in a
temporal succession, that is, according to the form of our own
internal sense. Time, therefore, is nothing by itself, nor is it a
determination inherent objectively in things.
VOL. II. D
34 OF TIME.
blematical), the other, when the form of the per-
ception of the object is taken into consideration; this
form belonging not to the object in itself, but to
the subject which perceives it, though nevertheless
belonging really and necessarily to the object as a
< v phenomenon.
Time and space are therefore two sources of know-
ledge from which various a priori synthetical [p. 39.]
cognitions can be derived. Of this pure mathematics
give a splendid example in the case of our cognitions
of space and its various relations. As they are both
pure forms of sensuous intuition, they render syn-
thetical propositions a priori possible. But these
sources of knowledge a priori (being conditions of
our sensibility only) fix their own limits, in that they
can refer to objects only in so far as they are con-
sidered as phenomena, but cannot represent things
as they are* by themselves. This is the only field in
which they are valid ; beyond it they admit of no
objective application. This peculiar reality of space
and time, however, leaves the truthfulness of our
experience quite untouched, because we are equally
sure of it, whether these forms are inherent in things
by themselves, or by necessity in our intuition of
them only. Those, on the contrary, who maintain
the absolute reality of space and time, whether as
subsisting or only as inherent, must come into conflict
with the principles of experience itself. For if they
admit space and time as subsisting (which is generally
the view of mathematical students of nature) they
have to admit two eternal infinite and self-subsist-
ing nonentities (space and time), which exist without
OF TIME. 35
their being anything real, only in order to compre-
hend all that is real. If they take the second [p. 40.]
view (held by some metaphysical students of nature),
and look upon space and time as relations of phe-
nomena, simultaneous or successive, abstracted from
experience, though represented confusedly in their
abstracted form, they are obliged to deny to ma-
thematical propositions a priori their validity with
regard to real things (for instance in space), or at
all events their apodictic certainty, which cannot take
place a posteriori, while the a priori conceptions of
space and time are, according to their opinion, crea-
tions of our imagination only. Their source, they
hold, must really be looked for in experience, imagina-
tion framing out of the abstract relations of experience
something which contains the general character of
these relations, but which cannot exist without
the restrictions which nature has imposed on them.
The former gain so much that they keep at least
the sphere of phenomena free for mathematical
propositions ; but, as soon as the understanding
endeavours to transcend that sphere, they become
bewildered by these very conditions. The latter have
this advantage that they are not bewildered by the
representations of space and time when they wish
to form judgments of objects, not as phenomena, but
only as considered by the understanding ; but they
can neither account for the possibility of mathe-
matical knowledge a priori (there being, according
to them, no true and objectively valid intuition,
a priori), nor can they bring the propositions e-^x-
perience into true harmony with the a priori doc-
D 2
36 OF TIME.
trines of mathematics. According to our [p. 41.]
theory of the true character of these original forms
of sensibility, both difficulties vanish.
Lastly, that transcendental aesthetic cannot con-
tain more than these two elements, namely, space
and time, becomes clear from the fact that all other
concepts belonging to the senses, even that of motion,
which combines both, presuppose something em-
pirical. Motion presupposes the perception of some-
thing moving. In space, however, considered by
itself, there is nothing that moves. Hence that
which moves must be something which, as in space,
can be given by experience only, therefore an em-
pirical datum. On the same ground, transcendental
aesthetic cannot count the concept of change among
its a 'priori data, because time itself does not change,
but only something which is in time. For this,
the perception of something existing and of the
succession of its determinations, in other words,
experience, is required.
GENEEAL OBSEEVATIONS ON
TRANSCENDENTAL ESTHETIC.
In order to avoid all misapprehensions it will be
necessary, first of all, to declare, as clearly as possible,
what is our view with regard to the funda- [p. 4 2 -]
mental nature of sensuous knowledge.
What we meant to say was this, that all our
intuition is nothing but the representation of phe-
nomena ) that things which we see are not by
themselves what we see, nor their relations by
themselves such as they appear to us, so that, if
we drop our subject or the subjective form of
our senses, all qualities, all relations of objects in
space and time, nay space and time themselves,
would vanish. They cannot, as phenomena, exist
by themselves, but in us only. It remains com-
pletely unknown to us what objects may be by
themselves and apart from the receptivity of our
senses. We know nothing but our manner of per-
ceiving them, that manner being peculiar to us, and
not necessarily shared in by every being, though, no
doubt, by every human being. This is what alone
concerns us. Space and time are pure forms of our
intuition, while sensation forms its matter. What we
can know a priori before all real intuition, are the
forms of space and time, which are therefore called
pure intuition, while sensation is that which causes
our knowledge to be called a posteriori knowledge,
38 GENERAL OBSERVATIONS
i.e. empirical intuition. Whatever our sensation may
be, these forms are necessarily inherent in it, while
sensations themselves may be of the most different
character. Even if we could impart the [p. 43.]
highest degree of clearness to our intuition, we should
not come one step nearer to the nature of objects by
themselves. We should know our mode of intuition,
i.e. our sensibility, more completely, but always under
the indefeasible conditions of space and time. What
the objects are by themselves would never become
known to us, even through the clearest knowledge
of that which alone is given us, the phenomenon.
It would vitiate the concept of sensibility and phe-
nomena, and render our whole doctrine useless and
empty, if we were to accept the view (of Leibniz and
Wolff), that our whole sensibility is really but a con-
fused representation of things, simply containing what
belongs to them by themselves, though smothered
under an accumulation of signs (Merkmal) and partial
concepts, which we do not consciously disentangle.
The distinction between confused and well-ordered
representation is logical only, and does not touch
the contents of our knowledge. Thus the concept
of Right, as employed by people of common sense,
contains neither more nor less than the subtlest
speculation can draw out of it, only that in the
ordinary practical use of the word we are not always
conscious of the manifold ideas contained in that
thought. But no one would say therefore that the
ordinary concept of Right was sensuous, containing
a mere phenomenon ; for Right can never [p. 44.]
become a phenomenon, being a concept of the under-
ON TRANSCENDENTAL ^ESTHETIC. 39
standing, and representing a moral quality belonging
to actions by themselves. The representation of a
Body, on the contrary, contains nothing in intuition
that could belong to an object by itself, but is merely
the phenomenal appearance of something, and the
manner in which we are affected by it. This re-
ceptivity of our knowledge is called sensibility. Even
if we could see to the very bottom of a phenomenon,
it would remain for ever altogether different from
the knowledge of the thing by itself.
This shows that the philosophy of Leibniz and
Wolf has given a totally wrong direction to all
investigations into the nature and origin of our
knowledge, by representing the difference between
the sensible and the intelligible as logical only.
That difference is in truth transcendental. It affects
not the form only, as being more or less confused,
but the origin and contents; so that by our sensibility
we do not know the nature of things by -themselves
confusedly only, but not /all. If we drop our subjec-
tive condition, the object, as represented with its
qualities bestowed on it by sensuous intuition, is
nowhere to be found, and cannot possibly be found ;
because its form, as phenomenal appearance, is de-
termined by those very subjective conditions.
It has been the custom to distinguish in [p. 45-]
phenomena that which is essentially inherent in
their intuition and is recognised by every human
being, from that which belongs to their intuition
accidentally only, being valid not for sensibility in
general, but only for a particular position and or-
ganisation of this or that sense. In that case the
40 GENERAL OBSERVATIONS
former kind of knowledge is said to represent the
object by itself, the latter its appearance only. But
that distinction is merely empirical. If, as generally
happens, people are satisfied with that distinction,
without again, as they ought, treating the first
empirical intuition as purely phenomenal also, in
which nothing can be found belonging to the thing
by itself, our transcendental distinction is lost, and
we believe that we know things by themselves,
though in the world of sense, however far we may
carry our investigation, we can never have any-
thing before us but mere phenomena. To give an
illustration. People might call the rainbow a mere
phenomenal appearance during a sunny shower, but
the rain itself the thing by itself. This would be
quite right, physically speaking, and taking rain as
something which, in our ordinary experience and
under all possible relations to our senses, can be de-
termined thus and thus only in our intuition. But
if we take the empirical in general, and ask, [p. 4 6 -]
without caring whether it is the same with every
particular observer, whether it represents a thing by
itself (not the drops of rain, for these are already, as
phenomena, empirical objects), then the question as
to the relation between the representation and the
object becomes transcendental, and not only the drops
are mere phenomena, but even their round shape, nay
even the space in which they fall, are nothing by them-
selves, but only modifications or fundamental disposi-
tions of our sensuous intuition, the transcendental
object remaining unknown to us.
The second important point in our transcendental
ON TRANSCENDENTAL ^ESTHETIC. 4 1
aesthetic is, that it should not only gain favour as a
plausible hypothesis, but assume as certain and un-
doubted a character as can be demanded of any
theory which is to serve as an organum. In order
to make this certainty self-evident we shall select a
case which will make its validity palpable.
Let us suppose that space and time are in them-
selves objective, and conditions of the possibility of
things by themselves. It would follow that there
must be with regard to both a large number of a
priori apodictic and synthetical propositions, and
particularly with regard to space, which for this
reason we shall chiefly investigate here as an
illustration. As the propositions of geometry are
known synthetically a priori, and with apodictic
certainty, I ask, whence do you take such pro-
positions \ and what does the understanding [p. 47.]
rely on in order to arrive at such absolutely necessary
and universally valid truths % There is no other way
but by concepts and -intuitions, and both are given
either a priori or a posteriori. The latter, namely
empirical concepts, as well as the empirical intuition
on which they are founded, cannot yield any syn-
thetical propositions except such as are themselves
also empirical only, that is, empirical propositions,
which can never possess that necessity and absolute
universality which are characteristic of all geometrical
propositions. As to the other and only means of
arriving at such knowledge through mere concepts
and intuitions a priori, it must be clear that
only analytical, but no synthetical knowledge can
ever be derived from mere concepts. Take the
42 GENERAL OBSERVATIONS
proposition that two straight lines cannot enclose
a space and cannot therefore form a figure, and
try to deduce it from the concept of straight lines
and the number two ; or take the proposition that
with three straight lines it is possible to form a
figure, and try to. deduce that from those concepts.
All your labour will be lost, and in the end you will
be obliged to have recourse to intuition, as is always
done in geometry. You then give yourselves an
object in intuition. But of what kind is it % [p. 4 8 .]
Is it a pure intuition a priori or an empirical one ?
In the latter case, you would never arrive at a
universally valid, still less at an apodictic proposition,
because experience can never yield such. You must
therefore take the object as given a priori in intui-
tion, and found your synthetical proposition on that.
If you did not possess in yourselves the power of
a priori intuition, if that subjective formal condition
were not at the same time the general condition
a priori under which alone the object of that (ex-
ternal) intuition becomes possible, if, in fact, the
object (the triangle) were something by itself without
any reference to a subject, how could you say that
what exists necessarily in your subjective conditions
of constructing a triangle, belongs of necessity to
the triangle itself? You could not add something
entirely new (the figure) to your concepts of three
lines, something which should of necessity belong to
the object, as that object is given before your know-
ledge of it, and not by it. If therefore space, and
time also, were not pure forms of your intuition, which
contains the a priori conditions under which alone
ON TRANSCENDENTAL AESTHETIC. 43
tilings can become external objects to you, while,
without that subjective condition, they are nothing,
you could not predicate anything of external objects
a priori and synthetically. It is therefore beyond
the reach of doubt, and not possible only or [p. 49-]
probable, that space and time, as the necessary
conditions of all experience, external and internal,
are purely subjective conditions of our intuition,
and. that, with reference to them, all things are
phenomena only, and not things existing by them-
selves in such or such wise. Hence, so far as their
form is concerned, much may be predicated of them
a priori, but nothing whatever of the things by them-
selves on which these phenomena may be grounded 1 .
1 Here follows in the Second Edition, Supplement XI.
THE
ELEMENTS OE TRANSCENDENTALISM. (M
SECOND PART.
TRANSCENDENTAL LOGIC.
INTRODUCTION.
THE IDEA OF A TRANSCENDENTAL LOGIC.
I.
Of Logic in General.
Our knowledge springs from two fundamental
sources of our soul ; the first receives representations
(receptivity of impressions), the second is the power
of knowing an object by these representations (spon-
taneity of concepts). By the first an object is given
us, by the second the object is thought, in relation
to that representation which is a mere determination
of the soul. Intuition therefore and concepts con-
stitute the elements of all our knowledge, so that
neither concepts without an intuition corresponding
to them, nor intuition without concepts can yield
any real knowledge.
Both are either pure or empirical. They are
empirical when sensation, presupposing the actual
presence of the object, is contained in it. They are
pure when no sensation is mixed up with the re-
TRANSCENDENTAL LOGIC. 45
presentation. The latter may be called the material
of sensuous knowledge. Pure intuition therefore
contains the form only by which something [p. 51.]
is seen, and pure conception the form only by which
an object is thought. Pure intuitions and pure con-
cepts only are possible a priori, empirical intuitions
and empirical concepts a posteriori.
We call sensibility the receptivity of our soul, or
its power of receiving representations whenever it is
in any wise affected, while the understanding, on the
contrary, is with us the power of producing re-
presentations, or the spontaneity of knowledge. We
are so constituted that our intuition must always be
sensuous, and consist of the mode in which we are
affected by objects. What enables us to think the
objects of our sensuous intuition is the understand-
ing. Neither of these qualities or faculties is pre-
ferable to the other. Without sensibility objects
would not be given to us, without understanding
they would not be thought by us. Thoughts with-
out contents are empty, intuitions without concepts are
blind. Therefore it is equally necessary to make our
concepts sensuous, i. e. to add to them their object in
intuition, as to make our intuitions intelligible, i.e.
to bring them under concepts. These two powers
or faculties cannot exchange their functions. The
understanding cannot see, the senses cannot think.
By their union only can knowledge be produced.
But this is no reason for confounding the share which
belongs to each in the production of knowledge. On
the contrary, they should always be carefully [p. 52.]
separated and distinguished, and we have therefore
46 TRANSCENDENTAL LOGIC.
divided the science of the rules of sensibility in
general, i.e. aesthetic, from the science of the rules
of the understanding in general, i.e. logic.
Logic again can be taken in hand for two objects,
either as logic of the general or of a particular use
of the understanding. The former contains all ne-
cessary rules of thought without which the under-
standing cannot be used at all. It treats of the
understanding without any regard to the different
objects to which it may be directed. Logic of the
particular use of the understanding contains rules
how to think correctly on certain classes of objects.
The former may be called Elementary Logic, the
latter the Ofganum of this or that science. The
latter is generally taught in the schools as a pre-
paration for certain sciences, though, according to
the real progress of the human understanding, it
is the latest achievement, which does not become
possible till the science itself is really made, and
requires only a few touches for its correction and
completion. For it is clear that the objects them-
selves must be very well known before it is possible
to give rules according to which a science of them
may be established.
General logic is either pure or applied. In [p. 53-]
the former no account is taken of any empirical con-
ditions under which our understanding acts, i.e. of
the influence of the senses, the play of imagina-
tion, the laws of memory, the force of habit, the
inclinations, and therefore the sources of prejudice
also, nor of anything which .supplies or seems to
supply particular kinds of knowledge ; for all this
TRANSCENDENTAL LOGIC. 47
applies to the understanding under certain circum-
stances of its application only, and requires expe-
rience as a condition of knowledge. General but
pure logic has to deal with principles a priori only,
and is a canon of the understanding and of reason,
though with reference to its formal application only,
irrespective of any contents, whether empirical or
transcendental. General logic is called applied, if it
refers to the rules of the use of our understanding
under the subjective empirical conditions laid down
in psychology. It therefore contains empirical prin-
ciples, yet it is general, because referring to the use
of the understanding, whatever its objects may be. It
is neither a canon of the understanding in general nor
an organum of any particular science, but simply a
catharticon of the ordinary understanding.
In general logic, therefore, that part which is
to constitute the science of pure reason must be
entirely separated from that which forms [p. 54.]
applied, but for all that still general logic. The
former alone is a real science, though short and dry,
as a practical exposition of an elementary science of
the understanding ought to be. In this logicians
should never lose sight of two rules :
i. As general logic it takes no account of the con-
tents of the knowledge of the understanding nor of
the difference of its objects. It treats of nothing
but the mere form of thought.
2. As pure logic it has nothing to do with em-
pirical principles, and borrows nothing from psycho-
logy (as some have imagined), because psychology
has no influence whatever on the canon of the under-
48 TRANSCENDENTAL LOGIC.
standing. It proceeds by way of demonstration, and
everything in it must be completely a priori.
What I call applied logic (contrary to common
usage according to which it contains certain exercises
on the rules of pure logic) is a representation of the
understanding and of the rules according to which
it is necessarily applied in concrete, i.e. under the
accidental conditions of the subject, which may
hinder or help its application, and are all given
empirically only. It treats of attention, its impe-
diments and their consequences, the sources of error,
the states of doubt, hesitation and conviction, etc. and
general and pure logic stands to it in the same [p-55.]
relation as pure ethics, which treat only of the neces-
sary moral laws of a free will, to applied ethics, which
consider these laws as under the influence of sen-
timents, inclinations and passions to which all human
beings are more or less subject. This can never con-
stitute a true and demonstrated science, because, like
applied logic, it depends on empirical and psycho-
logical principles.
II.
Of Transcendental Logic.
General logic, as we saw, takes no account of the
contents of knowledge, i.e. of any relation between
it and its objects, and considers the logical form only
in the relation of cognitions^ to each other, that is,
it treats of the form of thought in general. But as
we found, when treating of Transcendental ^Esthetic,
that there are pure as well as empirical intuitions,
TRANSCENDENTAL LOGIC. 49
it is possible that a similar distinction might appear
between pure and empirical thinking. In this case
we should have one logic in which the contents of
knowledge are not entirely ignored, while that logic
which contains the rules of pure thought only, would
exclude all knowledge of a merely empirical cha-
racter. It would also treat of the origin of our
knowledge of objects, so far as that knowledge is
not supplied by the objects themselves, while [p. 56]
general logic is not at all concerned with the origin
of our knowledge, but only considers representations,
whether existing originally a priori in ourselves or
empirically given to us, according to the laws fol-
lowed by the understanding, when thinking and