same subject； how； therefore； I am able to say： 〃I； as an intelligence
and thinking subject； cognize myself as an object thought； so far as I
am； moreover； given to myself in intuition… only； like other
phenomena； not as I am in myself； and as considered by the
understanding； but merely as I appear〃… is a question that has in it
neither more nor less difficulty than the question… 〃How can I be an
object to myself？〃 or this… 〃How I can be an object of my own
intuition and internal perceptions？〃 But that such must be the fact；
if we admit that space is merely a pure form of the phenomena of
external sense； can be clearly proved by the consideration that we
cannot represent time； which is not an object of external intuition；
in any other way than under the image of a line； which we draw in
thought； a mode of representation without which we could not cognize
the unity of its dimension； and also that we are necessitated to
take our determination of periods of time； or of points of time； for
all our internal perceptions from the changes which we perceive in
outward things。 It follows that we must arrange the determinations
of the internal sense； as phenomena in time； exactly in the same
manner as we arrange those of the external senses in space。 And
consequently； if we grant； respecting this latter； that by means of
them we know objects only in so far as we are affected externally；
we must also confess； with regard to the internal sense； that by means
of it we intuite ourselves only as we are internally affected by
ourselves； in other words； as regards internal intuition； we cognize
our own subject only as phenomenon； and not as it is in itself。*＇2＇
*Motion of an object in space does not belong to a pure science；
consequently not to geometry； because； that a thing is movable
cannot be known a priori； but only from experience。 But motion；
considered as the description of a space； is a pure act of the
successive synthesis of the manifold in external intuition by means of
productive imagination； and belongs not only to geometry； but even
to transcendental philosophy。
*＇2＇ I do not see why so much difficulty should be found in
admitting that our internal sense is affected by ourselves。 Every
act of attention exemplifies it。 In such an act the understanding
determines the internal sense by the synthetical conjunction which
it cogitates； conformably to the internal intuition which
corresponds to the manifold in the synthesis of the understanding。 How
much the mind is usually affected thereby every one will be able to
perceive in himself。
SS 21
On the other hand； in the transcendental synthesis of the manifold
content of representations； consequently in the synthetical unity of
apperception； I am conscious of myself； not as I appear to myself； nor
as I am in myself； but only that 〃I am。〃 This representation is a
thought； not an intuition。 Now； as in order to cognize ourselves； in
addition to the act of thinking； which subjects the manifold of
every possible intuition to the unity of apperception； there is
necessary a determinate mode of intuition； whereby this manifold is
given； although my own existence is certainly not mere phenomenon
（much less mere illusion）； the determination of my existence* Can only
take place conformably to the form of the internal sense； according to
the particular mode in which the manifold which I conjoin is given
in internal intuition； and I have therefore no knowledge of myself
as I am； but merely as I appear to myself。 The consciousness of self
is thus very far from a knowledge of self； in which I do not use the
categories； whereby I cogitate an object； by means of the
conjunction of the manifold in one apperception。 In the same way as
I require； for the sake of the cognition of an object distinct from
myself； not only the thought of an object in general （in the
category）； but also an intuition by which to determine that general
conception； in the same way do I require； in order to the cognition of
myself； not only the consciousness of myself or the thought that I
think myself； but in addition an intuition of the manifold in
myself； by which to determine this thought。 It is true that I exist as
an intelligence which is conscious only of its faculty of
conjunction or synthesis； but subjected in relation to the manifold
which this intelligence has to conjoin to a limitative conjunction
called the internal sense。 My intelligence （that is； I） can render
that conjunction or synthesis perceptible only according to the
relations of time； which are quite beyond the proper sphere of the
conceptions of the understanding and consequently cognize itself in
respect to an intuition （which cannot possibly be intellectual； nor
given by the understanding）； only as it appears to itself； and not
as it would cognize itself； if its intuition were intellectual。
*The 〃I think〃 expresses the act of determining my own existence。 My
existence is thus already given by the act of consciousness； but the
mode in which I must determine my existence； that is； the mode in
which I must place the manifold belonging to my existence； is not
thereby given。 For this purpose intuition of self is required； and
this intuition possesses a form given a priori； namely； time； which is
sensuous； and belongs to our receptivity of the determinable。 Now；
as I do not possess another intuition of self which gives the
determining in me （of the spontaneity of which I am conscious）；
prior to the act of determination； in the same manner as time gives
the determinable； it is clear that I am unable to determine my own
existence as that of a spontaneous being； but I am only able to
represent to myself the spontaneity of my thought； that is； of my
determination； and my existence remains ever determinable in a
purely sensuous manner； that is to say； like the existence of a
phenomenon。 But it is because of this spontaneity that I call myself
an intelligence。
Transcendental Deduction of the universally possible
employment in experience of the Pure Conceptions
of the Understanding。 SS 22
In the metaphysical deduction； the a priori origin of categories was
proved by their plete accordance with the general logical of
thought； in the transcendental deduction was exhibited the possibility
of the categories as a priori cognitions of objects of an intuition in
general （SS 16 and 17）。At present we are about to explain the
possibility of cognizing； a priori； by means of the categories； all
objects which can possibly be presented to our senses； not； indeed；
according to the form of their intuition； but according to the laws of
their conjunction or synthesis； and thus； as it were； of prescribing
laws to nature and even of rendering nature possible。 For if the
categories were inadequate to this task； it would not be evident to us
why everything that is presented to our senses must be subject to
those laws which have an a priori origin in the understanding itself。
I premise that by the term synthesis of apprehension I understand
the bination of the manifold in an empirical intuition； whereby
perception； that is； empirical consciousness of the intuition （as
phenomenon）； is possible。
We have a priori forms of the external and internal sensuous
intuition in the representations of space and time； and to these
must the synthesis of apprehension of the manifold in a phenomenon
be always formable； because the synthesis itself can only take
place according to these forms。 But space and time are not merely
forms of sensuous intuition； but intuitions themselves （which
contain a manifold）； and therefore contain a priori the
determination of the unity of this manifold。* （See the Transcendent
Aesthetic。） Therefore is unity of the synthesis of the manifold
without or within us； consequently also a conjunction to which all
that is to be represented as determined in space or time must
correspond； given a priori along with （not in） these intuitions； as
the condition of the synthesis of all apprehension of them。 But this
synthetical unity can be no other than that of the conjunction of
the manifold of a given intuition in general； in a primitive act of
consciousness； according to the categories； but applied to our
sensuous intuition。 Consequently all synthesis； whereby alone is
even perception possible； is subject to the categories。 And； as
experience is cognition by means of conjoined perceptions； the
categories are conditions of the possibility of experience and are
therefore valid a priori for all objects of experience。
*Space represented as an object （as geometry really requires it to
be） contains more than the mere form of the intuition； namely； a
bination of the manifold given according to the form of sensibility
into a representation that can be intuited； so that the form of the
intuition gives us merely the manifold； but the formal intuition gives
unity of representation。 In the aesthetic； I regarded this unity as
belonging entirely to sensibility； for the purpose of indicating
that it antecedes all conceptions； although it presupposes a synthesis
which does not belong to sense； thr