METAPHYSIC S, 
213 
taphyfics; but the very poflibility of Metaphyfics depends 
upon Tranlcendental Fhilofophy. Since then an entire 
fcience, wholly deprived of every afiiftance from all others, 
and" absolutely new in itfelf, is neceflary to anfwer one 
finale queftion ; can it be wonderful that this lolution is 
attended with trouble and difficulty, na}', even at fir ft 
with fome oblcurity. 
Proceeding now to the folution oFtliis problem, accord¬ 
ing to the analytical method, in which we pre-fuppofe 
knowledge from jmre reefon to be real; we can only refer 
to two iciences of theoretical knowledge, (fuch only being 
here in quelticn,) pure Mathematics and pure Natural Thi- 
lofophy ; for thefe are the on!}'- two which can reprefent to 
it's objefls in .the intuititpi, and which confequentiy, when 
a knowledge a priori precedes the objefts, are alone able 
to ihow its truth or agreement with them in the concrete ; 
i. e. its reality, whence we may proceed analytically to 
the ground of its poflibility. This greatly eafes our la¬ 
bour, fir.ee univerfal contemplations are here not only 
applied to fails, but even proceed from them, whereas, in 
the fynthetical method, they mull be derived loiely in ab- 
jlra&o from conceptions. 
But, -in order to afeend from this pure knowledge, 
a priori, to the Metapliyfics as a fcience, it is neceflary to en¬ 
quire into their foundation or groundwork, namely, know¬ 
ledge a priori, which, when treated without a critical in- 
veftigation oi its poflibility, is itfelf commonly termed 
Metaphyfics. In a word, it is neceflary to comprile the 
natural foundation of luch a fcience in our chief tranf- 
cendental queltion, which is thus lubdivided into four 
others.: 
i. How are pure Mathematics poflible ? 
z. How is pure Natural Philofophy poflible? 
3. How are Metaphyfics in General poflible? 
4. How are Metaphyfics, as a Science, poflible ? 
It will be eafily feen that, although the folution of thefe 
■problems appears at firft fight to be a mere recapitulation 
of the chief contents of the “ Critic,” there is ftiil fiome- 
thing peculiar in the objedl which it has in view that de- 
ferves attention ; namely, the delign of learching for the 
fources of given fciences in Realon itfelf, and of judging 
by the adtual fa£t of the power which Realon poflefles to 
obtain knowledge a priori. It tends thus to improve the 
fciences themlelVes, not by adding to their contents, but 
by {flowing their proper ule, and throwing a new light 
upon the higher queftion regarding their common origin. 
Firft Tranfcendental Queftion. 
ITow are pure Mathematics poflible ? 
We have here to confider an immenfe ftore of know¬ 
ledge, already of aftonilhmg extent, and ftill promifmg an 
•unlimited increafe, carrying with it apodidtical certainty; 
in other words, abfolute necefiity, the whole of which is, 
the pure product of realon, and entirely fynthetical. How 
is it'poflible, that human realon can produce this know¬ 
ledge a priori! 
We find thatmll mathematical knowledge has this pe¬ 
culiarity, that it requires its conceptions to be reprefented 
in the intuition a priori; that is, in fuch an intuition as is 
not.empirical, but pure ; and that, without this, the Ma¬ 
thematics cannot proceed one Angle ftep. Hence it is, 
that their judgments are always intuitive, whereas philo¬ 
fophy mull content itfelf with difcurfive judgments merely 
derived from conceptions. It may indeed illuftrate its 
apodidtical doctrines by intuition, but never can derive 
them from it. This obfervation with refpedl to the nature 
of Mathematics, gives us a diredlion to the firft and chief 
condition of their poflibility, namely, a pure intuition. 
This alone, enables them to reprefent their conceptions 
in the concrete, and yet a priori; that is to fay, originally 
to cor.flruB them. If then we are able to difeover this 
pure "intuition and its poflibility, it will be ealy to explain 
how fynthetical politions a priori are poflible in pure Ma- 
thematics; in other words, how this fcience itfelf is pof¬ 
lible ; for, as the empirical intuition enables us to extend 
fynthetically our conception of an objedl in experience, 
by new predicates, which that intuition itfelf furnilhes ; 
fo alfo will the pure intuition enable us to extend our 
conception fynthetically; only with this difference, that, 
in the latter cafe, the fynthetical judgment will be a priori 
and apodidlicai, while in the former it is apqfteriori, and 
but contingent, fince it contains that which is met with 
in the accidental empirical intuition ; whereas pure intui¬ 
tion furnilhes nothing but what is neceffarily connected 
with the conception a priori. 
It may leem, however, that this ftep rather tends to in¬ 
creafe than to diminilh the difficulty; for it will now be 
afleed. How is it poflible to have an intuition a priori, fince 
Intuition is a Reprefentation that depends upon the im¬ 
mediate prefence of an objedt ? and this wouid imply an 
intuition without any objedl, either pall or prefent, and 
which confequentiy would be no intuition at all. Con¬ 
ceptions are indeed of fuch a nature, that fome may be 
a priori; namely, thole by which we think of an object in 
general, without finding ourfelves in any connection with 
the objedt; for inftance, the Conception of Quality, of 
Caufc, Sec. yet even thefe, in order to have any ftgnifica- 
tion, require a certain ule in the concrete, that is, an ap¬ 
plication to fome intuition, by which the objeCt of them 
is given to us. But how can the intuition of an objeCl 
precede the objeCt itfelf ? 
If our intuitions were of that kind that they reprefented 
the things as they are in themfelves, then indeed there 
could be no intuition a priori, it would always be empi¬ 
rical : for what appertains to the objeCl in itfelf, I can 
only know while it is prefent to me. Indeed it is even 
then inconceivable how my intuition of a prefent objeCl 
can make me know what it is in itfelf. However, grant¬ 
ing its poflibility, fuch intuition could not occur a priori, 
that is, before the objeCl has been prefented to me, for, 
without this, no ground of conneClion can be conceived 
between it and my reprefentation, unlels it reft upon in- 
fpiration. There is therefore only one poifible way in 
which intuition can precede the reality of objeCts, and 
take place as knowledge a priori; namely, that the intui¬ 
tion Jhall contain nothing but the form of the J'enJitive faculty 
itfelf, which lies in us antecedent to all real itnprejjion of ob¬ 
jects. For that intuitions of fenlible objects can occur 
agreeably to the form of the fenfitive faculty, I may know 
a priori. Such pojitions, therefore, as concern merely this 
form of fenlible intuition, may be known a priori to be 
poflible and valid of .the objeCts of fenfe ; and it is equally 
clear, that fuch intuitions as are poflible a priori, can re¬ 
late folely to ienfible objeCls. 
It is then only by means of the form of fenlible intui¬ 
tion, that we can poflibiy have intuition of things a priori; 
but hence it is evident, that we can know objeCts only as 
they appear to us (to our fenfes), not as they are in them- 
J'elves ; and this therefore mull abfolutely be admitted be¬ 
fore fynthetical politions a priori can be allowed to be pof¬ 
lible, or rather lince we find them real, in order that their 
poflibility may be conceived and determined. 
Now Time and Space are tiiofe intuitions, which pure 
mathematics lay down as a foundation for all the judg¬ 
ments and knowledge, which they give, us as apodiClical 
and nec.eflary; for Mathematics mult reprelent their con¬ 
ceptions firft in the intuition, and pure Mathematics in 
pure intuition; i. e. muft conllruCl their conceptions. 
Since they cannot proceed analytically, but only fyntheti¬ 
cally, it follows that they cannot advance one ftep with¬ 
out pure intuition, and by which alone the matter for 
fynthetical judgments a priori can be given. Geometry, 
therefore, takes the pure intuition of Space for its foun¬ 
dation ; Arithmetic conftruCls its numerical conceptions 
by the fucceffive fynthelis of unities in Time. In pure 
mechanics alfo, there can be no conceptions of motion, 
but by means of the reprelentation of time. But Time 
and Space are merely intuitions ; for, if we abftrail from 
the empirical intuition of bodies, and tlieir changes (nw, 
tion), 
