§ 49. That there is something real without us which not only
corresponds, but must correspond, to our external perceptions, can
likewise be proved to be not a connexion of things in themselves, but
for the sake of experience. This means that there is something
empirical, i.e., some phenomenon in space without us, that admits of a
satisfactory proof, for we have nothing to do with other objects than
those which belong to possible experience; because objects which
cannot be given us in any experience, do not exist for us. Empirically
without me is that which appears in space, and space, together with
all the phenomena which it contains, belongs to the representations,
whose connexion according to laws of experience proves their objective
truth, just as the connexion of the phenomena of the internal sense
proves the actuality of my soul (as an object of the internal sense).
By means of external experience I am conscious of the actuality of
bodies, as external phenomena in space, in the same manner as by means
of the internal experience I am conscious of the existence of my soul
in time, but this soul is only cognised as an object of the internal
sense by phenomena that constitute an internal state, and of which the
essence in itself, which forms the basis of these phenomena, is
unknown. Cartesian idealism therefore does nothing but distinguish
external experience from dreaming; and the conformity to law (as a
criterion of its truth) of the former, from the irregularity and the
false illusion of the latter. In both it presupposes space and time as
conditions of the existence of objects, and it only inquires whether
the objects of the external senses, which we when awake put in space,
are as actually to be found in it, as the object of the internal
sense, the soul, is in time; that is, whether experience carries with
it sure criteria to distinguish it from imagination. This doubt,
however, may be easily disposed of, and we always do so in common life
by investigating the connexion of phenomena in both space and time
according to universal laws of experience, and we cannot doubt, when
the representation of external things throughout agrees therewith,
that they constitute truthful experience. Material idealism, in which
phenomena are considered as such only according to their connexion in
experience, may accordingly be very easily refuted; and it is just as
sure an experience, that bodies exist without us (in space), as that I
myself exist according to the representation of the internal sense (in
time): for the notion without us, only signifies existence in space.
However as the Ego in the proposition, "I am," means not only the
object of internal intuition (in time), but the subject of
consciousness, just as body means not only external intuition (in
space), but the thing-in-itself, which is the basis of this
phenomenon; [as this is the case] the question, whether bodies (as
phenomena of the external sense) exist as bodies apart from my