PHILOSOPHY, 
204 
Now Idealism overthrows the conclufion that fenfa- 
tion proves the exiitence of objedts, which we maintain 
are reprefented by means of fenfation as real. This then 
is the proper place for its refutation. 
Idealil'm is either the dogmatical of Berkeley, which 
completely denies the exiftence of external objedts, or the 
problematical of Defcartes, which reprefents it as doubtful. 
Both of thefe great men held the / am as undoubtedly 
certain. They may be immediately refuted, by fhowing 
that the confcioufnefs of our own exiftence is only poffible 
under the prefuppolition of the exiftence of external 
things. 
Theorem. The empirical determination of the confciouf¬ 
nefs of our own exiftence, proves the exiftence of objects in 
fpace, external to us. 
Proof. I am confcious of my exiftence as determined 
in time. This determination of it arifes hereby, that I 
confider my own exiftence in connexion with that of other 
objects reprefented by myfelf. The queftion now occurs, 
whether thefe latter are merely imaginary, or real objedts 
in fpace external to me. If they were the former, then 
would the external objects be nothingbut reprefentations. 
All determinations of time, however, prefuppofe a perma¬ 
nent fubftratum. If now this is not contained in the 
reprefented external objects, then the reprefentations 
themfelves mu ft contain this permanent. But all our 
reprefentations are changeable, and the determination of 
them in time is included in the determination of my own 
exiftence. Confequently the external objects are not 
merely reprefentations, but really-exifting external things, 
that contain the permanent fubftratum in themfelves, by 
means of which I am convinced of my own exiftence in 
time. 
The proof begins from a faff, namely, the confcioufnefs 
of my own exiftence in time. This is not identical with 
the pure I am. For I am or 1 think is nothing but trans¬ 
cendental confcioufnefs, the confcioufnefs of my connedt- 
ing faculty, whereby I am convinced of the lynthefis of 
reprefentations themfelves, and bring different reprefenta¬ 
tions to a unity of confcioufnefs. But the I am, whereby 
I determine my exiftence in time, requires external objedts, 
with whofe exiftence my own ftands in connexion. I 
determine myfelf in time, fince I confider myfelf as exifting 
at a time in which certain changes took place in the 
world ; I determine my exiftence by the courfe of the 
things in the world, See. Now I afk, Are thefe changes, 
namely, the ordinary courfe of the things in the world, 
merely imaginary, or are they really exifting objedts? All 
determinations of time take place from a change in refer¬ 
ence to a permanent, which itfelf undergoes a change. 
From my own reprefentations I can by no means determine 
my exiftence in time; for thefe belong altogether to myfelf, 
whofe exiftence I alfo determine in myfelf. Confequently 
the reprefented objects are not mere reprefentations, but 
really exifting things external to me, in which is the per¬ 
manent fubftratum by which I determine my exiftence in 
time. We muft however remark, that we cannot con¬ 
clude, from the mere change of reprefentations, the exift- 
er.ee of objects in fpace correfponding with them. For it 
is indeed clear, that, as the reprefentations change, fome- 
thing permanent muft lie at the bottom ; but the queftion 
concerning it is always independent of that, whether 
thefe reprefentations are merely imaginary, or whether 
exifting objedts correfpond to them. The empirical con- 
feionfnefs of my exiftence in time, which includes alfo the 
exiftence of my reprefentations in time, render the latter 
prefuppolition neceffary. But, as to the diftindtion of 
imaginary from real things, in particular cafes, we muft 
have particular rules for each fingle cafe. 
Idealifm a flumes, that internal experience is immedi¬ 
ately certain; and that we thence conclude external ob¬ 
jects; this is however unfatisfadtory, becaufe the effedts 
that we aferibe to external things, reprefentations, may 
perhaps have their caufe in ourfelves. On the other hand, 
it is Ihown by our Theorem, that not internal but exter¬ 
nal experience is immediately certain, and that the deter¬ 
mination of our own exiftence is only poffible from expe¬ 
rience. If an intuition were to form the foundation of 
the pure confcioufnefs I am, then it would not be necef¬ 
fary for the determination of my exiftence in time to con¬ 
fider it in connexion with the exiftence of external objects; 
but I ffioiild determine my exiftence immediately by this 
internal intuition. But, on the contrary, as the repre- 
fentation I am is entirely empty, and has no meaning ex¬ 
cept from reprefented objedts; Internal Experience, that 
is, the confcioufnefs of our exiftence, is not poffible but 
by External Experience. 
The third Poftulate relates to objective neceffity. It 
does not therefore imply neceffity in thought merely, but 
in exiftence. Now there is no exiftence that can be abfo- 
lutely known a priori, except the exiftence of effedts, the 
caufes of which have previoufly exifted. One exiftence 
therefore may indeed be known to be neceffary, in fo far 
as it is related to another, but not by itfelf alone; confe¬ 
quently, there is no individual fubftance whofe exiftence 
is abfolutely neceffary. It is only to effedts as related to 
their caufes, that this neceffity can be aferibed. 
General Remarks on the Syftem of Principles. 
The deduction of the Categories has (liown, that thefe 
pure conceptions reprefent the connexion of the variety of 
an intuition in a certain manner as neceffary, and thereby 
produce the reprefentation of an objedt. Now, as thefe 
conceptions a priori refer to objects, the underftanding muft 
contain, briides them, the rules of the application to em¬ 
pirical objects, which are the principles juft treated of. 
No wonder, therefore, that thefe conceptions are fuch 
that we cannot affure ourfelves of their objediive reality, 
without confidering them in reference to intuition. For 
in that cafe the judgment has no rules of application ; 
and we cannot at all know whether the conceptions really 
refer to objedts or not. That there fliould be an objedt 
whofe parts are homogeneous, that is, have quantity ; 
that, notwithftanding thefe parts are perceived by a 
fuccelfive fynthefis, yet that they a rile ali at once; that it 
fliould be (omething that can exift merely as fubjedt, but 
never as the determination of other things; that it (hould 
be fo qualified ; that, when it exifts, fomething elfe muft 
therefore neceffarily exift; and that a multitude of fuch 
objedts (hould mutually influence One another; laftly, 
that we can think of thele objedts as poffible, exifting, of 
neceflary;-—all thefe rules muft appear to us as fo many 
arbitrary determinations, that we could with no propriety 
aferibe to objedts, were it not that they are the very appli¬ 
cation of the Laws of the Underftanding, the Categories, 
to empirical intuition. 
Thefe principles are altogether fynthetical, and can 
only be proved in reference to poffible experience ; that 
is, only fofaras-objedtscan be reprefented in the intuition. 
If now we abftradt from the intuition, it is quite impoffible 
to comprehend this fynthefis. We can then ftill unite 
thefe pure conceptions of underftanding with each other; 
but, as the neceffary unity of intuition is no further 
underftood, it muft be quite arbitrary, and cannot be 
proved. If they are not proved from the principle of 
poffible experience, they muft be confidered as analytical; 
and we can only look for their proof in the development 
of conceptions. We ufually perfuade ourfelves in this 
fearch, that the predicate is already to be found in the 
fubjedt. The pofition of Caufality furniflies a remarkable 
inftance of this. It is thus exprelfed; ‘‘Every contingent 
exifting thing muft have a caufe;’' underftanding by 
contingent, that which comprifes in it, not the Categories 
of Modality, (as fomething whofe non-exiftence may 
be thought,) but thofe of Relation, (as fomething that 
can only exift as a confequence of fomething elfe.) We 
then have the identical pofition : That which can only 
exift as a confequence muft have a caufe. Contingent is 
that, which may or may not be in a certain time. This 
conception of contingency is not identical with that of 
change. 
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