Knowing the World 91is expressible only through concepts. Only if I couldper-
ceive how the percept of an object affects the percept of
the subject, or—conversely—only if I could observe the
construction of a perceptual form by the subject, would it
be possible to speak like modern physiology and the crit-
ical idealism built upon it. This view confuses an ideal re-
lation (of the object to the subject) with a process that
could only be spoken of if it were perceived. Therefore
the phrase, “no color without a color-sensing eye” cannot
mean that the eye produces color, but only that a concep-
tual connection, knowable through thinking, exists be-
tween the percept “color” and the percept “eye.”
Empirical science will have to ascertain how the qualities
of the eye and those of color relate to one another and how
the organ of sight transmits the perception of colors, etc.
I can track how one percept follows another and how it
stands in spatial relation to others. I can then bring this to
conceptual expression. But I cannot perceive how a per-
cept proceeds out of the unperceivable. All efforts to seek
other than conceptual relations between percepts must
necessarily fail.
What, then, is a percept? Asked in this general way, the
question is absurd. A percept always appears as a quite
specific, concrete content. This content is immediately
given and is limited to what is given. Of what is given, we
can ask only what it is apart from perception—that is,
what it is for thinking. Therefore the question ofwhata
percept is can aim only at the conceptual intuition corre-
sponding to it. From this perspective, the question of the
subjectivity of the percept, in the sense meant by critical