something real； and the simplicity of its nature is given in the
very fact of its possibility。 Now in space there is nothing real
that is at the same time simple； for points； which are the only simple
things in space； are merely limits； but not constituent parts of
space。 From this follows the impossibility of a definition on the
basis of materialism of the constitution of my Ego as a merely
thinking subject。 But； because my existence is considered in the first
proposition as given； for it does not mean； 〃Every thinking being
exists〃 （for this would be predicating of them absolute necessity）；
but only； 〃I exist thinking〃； the proposition is quite empirical；
and contains the determinability of my existence merely in relation to
my representations in time。 But as I require for this purpose
something that is permanent； such as is not given in internal
intuition； the mode of my existence； whether as substance or as
accident； cannot be determined by means of this simple
self…consciousness。 Thus； if materialism is inadequate to explain
the mode in which I exist； spiritualism is likewise as insufficient；
and the conclusion is that we are utterly unable to attain to any
knowledge of the constitution of the soul； in so far as relates to the
possibility of its existence apart from external objects。
And； indeed； how should it be possible； merely by the aid of the
unity of consciousness… which we cognize only for the reason that it
is indispensable to the possibility of experience… to pass the
bounds of experience （our existence in this life）； and to extend our
cognition to the nature of all thinking beings by means of the
empirical… but in relation to every sort of intuition； perfectly
undetermined… proposition； 〃I think〃？
There does not then exist any rational psychology as a doctrine
furnishing any addition to our knowledge of ourselves。 It is nothing
more than a discipline； which sets impassable limits to speculative
reason in this region of thought； to prevent it； on the one hand； from
throwing itself into the arms of a soulless materialism； and； on the
other； from losing itself in the mazes of a baseless spiritualism。
It teaches us to consider this refusal of our reason to give any
satisfactory answer to questions which reach beyond the limits of this
our human life； as a hint to abandon fruitless speculation； and to
direct； to a practical use； our knowledge of ourselves… which；
although applicable only to objects of experience； receives its
principles from a higher source； and regulates its procedure as if our
destiny reached far beyond the boundaries of experience and life。
From all this it is evident that rational psychology has its
origin in a mere misunderstanding。 The unity of consciousness； which
lies at the basis of the categories； is considered to be an
intuition of the subject as an object； and the category of substance
is applied to the intuition。 But this unity is nothing more than the
unity in thought； by which no object is given； to which therefore
the category of substance… which always presupposes a given intuition…
cannot be applied。 Consequently； the subject cannot be cognized。 The
subject of the categories cannot； therefore； for the very reason
that it cogitates these； frame any conception of itself as an object
of the categories； for； to cogitate these； it must lay at the
foundation its own pure self…consciousness… the very thing that it
wishes to explain and describe。 In like manner； the subject； in
which the representation of time has its basis； cannot determine；
for this very reason； its own existence in time。 Now； if the latter is
impossible； the former； as an attempt to determine itself by means
of the categories as a thinking being in general； is no less so。*
*The 〃I think〃 is； as has been already stated； an empirical
proposition； and contains the proposition； 〃I exist。〃 But I cannot
say； 〃Everything； which thinks； exists〃； for in this case the property
of thought would constitute all beings possessing it； necessary
being Hence my existence cannot be considered as an inference from the
proposition； 〃I think；〃 as Descartes maintained… because in this
case the major premiss； 〃Everything； which thinks； exists；〃 must
precede… but the two propositions are identical。 The proposition； 〃I
think；〃 expresses an undetermined empirical intuition； that perception
（proving consequently that sensation； which must belong to
sensibility； lies at the foundation of this proposition）； but it
precedes experience； whose province it is to determine an object of
perception by means of the categories in relation to time； and
existence in this proposition is not a category； as it does not
apply to an undetermined given object； but only to one of which we
have a conception； and about which we wish to know whether it does
or does not exist； out of； and apart from this conception。 An
undetermined perception signifies here merely something real that
has been given； only； however； to thought in general… but not as a
phenomenon； nor as a thing in itself （noumenon）； but only as something
that really exists； and is designated as such in the proposition； 〃I
think。〃 For it must be remarked that； when I call the proposition；
〃I think；〃 an empirical proposition； I do not thereby mean that the
Ego in the proposition is an empirical representation； on the
contrary； it is purely intellectual； because it belongs to thought
in general。 But without some empirical representation； which
presents to the mind material for thought； the mental act； 〃I
think；〃 would not take place； and the empirical is only the
condition of the application or employment of the pure intellectual
faculty。
Thus； then； appears the vanity of the hope of establishing a
cognition which is to extend its rule beyond the limits of experience…
a cognition which is one of the highest interests of humanity； and
thus is proved the futility of the attempt of speculative philosophy
in this region of thought。 But； in this interest of thought； the
severity of criticism has rendered to reason a not unimportant
service； by the demonstration of the impossibility of making any
dogmatical affirmation concerning an object of experience beyond the
boundaries of experience。 She has thus fortified reason against all
affirmations of the contrary。 Now； this can be acplished in only
two ways。 Either our proposition must be proved apodeictically； or； if
this is unsuccessful； the sources of this inability must be sought
for； and； if these are discovered to exist in the natural and
necessary limitation of our reason； our opponents must submit to the
same law of renunciation and refrain from advancing claims to dogmatic
assertion。
But the right； say rather the necessity to admit a future life； upon
principles of the practical conjoined with the speculative use of
reason； has lost nothing by this renunciation； for the merely
speculative proof has never had any influence upon the mon reason
of men。 It stands upon the point of a hair； so that even the schools
have been able to preserve it from falling only by incessantly
discussing it and spinning it like a top； and even in their eyes it
has never been able to present any safe foundation for the erection of
a theory。 The proofs which have been current among men； preserve their
value undiminished； nay； rather gain in clearness and
unsophisticated power； by the rejection of the dogmatical
assumptions of speculative reason。 For reason is thus confined
within her own peculiar province… the arrangement of ends or aims；
which is at the same time the arrangement of nature； and； as a
practical faculty； without limiting itself to the latter； it is
justified in extending the former； and with it our own existence；
beyond the boundaries of experience and life。 If we turn our attention
to the analogy of the nature of living beings in this world； in the
consideration of which reason is obliged to accept as a principle that
no organ； no faculty； no appetite is useless； and that nothing is
superfluous； nothing disproportionate to its use； nothing unsuited
to its end； but that； on the contrary； everything is perfectly
conformed to its destination in life… we shall find that man； who
alone is the final end and aim of this order； is still the only animal
that seems to be excepted from it。 For his natural gifts… not merely
as regards the talents and motives that may incite him to employ them；
but especially the moral law in him… stretch so far beyond all mere
earthly utility and advantage； that he feels himself bound to prize
the mere consciousness of probity； apart from all advantageous
consequences… even the shadowy gift of posthumous fame… above
everything； and he is conscious of an inward call to constitute
himself； by his conduct in this world… without regard to mere
sublunary interests… the citizen of a better。 This mighty；
irresistible proof… acpanied by an ever…increasing knowledge of the
conformability to a purpose in everything we see around us； by the
conviction of the boundless immensity of creation； by the
consciousness of a certain illimitableness in the possible extension
of our knowledge； and by a desire mensurate therewit