Some terminology:

Lecture 22 on Kant II: Transcendental Idealism
Phil 212
I. Some terminology:
A. Transcendental: “I call all cognition transcendental that is occupied not so much with objects
but rather with our mode of cognition of objects insofar as this is to be possible a priori” (B25).
Transcendental theorizing is primarily about the conditions under which we do and must cognize
objects, rather than with the cognitions themselves.
B. Representation: A very general term covering intuitions, concepts, and most other mental
C. Intuition (Anschauung): A manner of relating immediately to objects. In us, it is the “matter”
of empirical cognition, and is given to us through sensibility.
D. Concept: A general representation which applies to many (at least possible) objects, and
picks them out by way of a distinguishing “mark.” Concepts provide the “form” of our
cognitions, and are applied by the understanding.
E. Sensibility: The capacity (or, better, receptive capacity) to acquire representations by being
affected by outer objects.
F. Thought, thinking: The capacity (active, rather than merely receptive) to use concepts in
making judgments. In combination with intuition, thinking produces cognition or knowledge.
Thought is the “form” of cognition. Mere thinking involves playing with concepts in the absence
of intuition. Mere thinking can’t produce cognition or knowledge.
G. Understanding: The faculty of the mind which thinks, i.e., which uses concepts in making
H. Cognition: The product of intuition and thought—i.e., the mental act (or result of such an act)
of uniting intuited representations under concepts in the form of judgments.
I. Reason (in the strict sense): The faculty of the mind which uses syllogisms and other forms of
argument to go beyond what we get from experience. It is also responsible for mistakenly
pushing us beyond the realm of experience altogether and engaging in mere metaphysical groping
among empty concepts.
II. Intuitions and Concepts
A. An intuition on its own does not count as any sort of knowledge. There is no mere
‘knowledge by acquaintance’ in Kant; the use of concepts in the formation of a judgment is
always required.
B. On the other hand, a concept by itself also doesn’t provide any (non-analytic) knowledge:
there has to be some relation to an intuition.
III. The “regressive” argument from the axioms of space and time (see note on the
“regressive” method at 4:277)
A. Assume that geometry and chronometry are successful sciences of synthetic a priori truths.
1. Example: A straight line is the shortest distance between two points. (4:269)
2. Example: Space has three dimensions. (4:284-5)
3. Example: A cube has eight corners.
4. Example: Two different times are always successive (and never simultaneous). (B49)
B. Regressive argument: In order for these to be true, space (which is the realm that the principles
of geometry govern) and time (the realm that the principles of chronometry) must be given as a
priori intuitions.
1. They must be given a priori rather than a posteriori as a kind of container or set of
relations out there in the world, since otherwise these sciences themselves could not be a
2. They must be intuitions (rather than concepts), since otherwise the principles of these
sciences could not be synthetic.
C. The conclusion, then, is that only under the assumption that space and time are fundamentally
a priori intuitions—can the principles of geometry and chronometry be what they are, or what we
all agree that they are.
IV. Transcendental Idealism
A. Space and time are not properties of things in themselves (contra Newton), and they are not
constituted by relations between things in themselves (contra Leibniz).
*Why? “If our intuition had to be of the kind that represented things as they are in
themselves, then absolutely no intuition a priori would take place, but it wuld always be
empirical. For I can only know what may be contained in the object in itself if the object
is present and given to me” (4: 282).
B. Space and time are “nothing other” than a “subjective condition of sensibility”… “a pure
intuition, in which all objects must be determined” (B42).
1. Note: Kant is only speaking of humans now—or, at least, beings with receptive
capacities as well as active thinking capacities.
C. Thus, space is “real” when we consider it from the point of view of what we could possibly
experience, but “ideal” from a “transcendental” perspective: i.e., from a point of view that
abstracts from “the constitution of our sensibility” (B44). In the first Critique, Kant calls his view
“transcendental idealism.” In the Prolegomena, he prefers the term “critical idealism” (4: 293).
D. There is a difference between space-time and its properties and the “secondary qualities” of
smell, taste, sight, and so forth. The latter are not even empirically real: they are merely the
subjective effects of objects in space affecting our sense-faculties. Spatio-temporal properties,
on the other hand, are empirically real: they are objective and non-relative. We can discern
what’s “really” out there in the empirical world by appeal to connectedness (4:290). But objects
in space and time are still, at bottom, transcendentally ideal.
Transcendentally real: Real überhaupt, even when considered in abstraction from our
mode of cognizing.
Transcendentally ideal: Ideal, or unreal, when considered in abstraction from our mode of
Empirically real: Real when considered from the point of view of our mode of cognizing.
Empirically ideal: Ideal, or unreal, even when considered merely from the point of view
of our mode of cognizing.
*think of the transcendental viewpoint as in a way God’s viewpoint. Space does
not exist from God’s viewpoint, but it’s very real from ours.
*Each of these can be turned into isms. You can be a transcendental realist about
some set of objects, and a transcendental idealist about another. Kant’s
transcendental idealism is about space and time, and about spatial and temporal
properties that we ascribe to objects. They are empirically real, but
transcendentally ideal.
V. Trendelenburg’s “neglected alternative” objection (1862)
A. Why can’t S&T be both subjective forms of our intuition and objective forms of things in
1. Kant in the Prolegomena seems to address this in saying that it is as ridiculous as
thinking both that something red causes a red sensation in me and is itself also red.
Suppose we decide to use “red” to refer to the phenomenological episode, and we also
know that there are some facts about molecules and wavelengths of light be reflected and
so forth that are causally responsible, together with my own neural equipment, for the
appearance of red to me. It seems senseless to say that we are neglecting the alternative
that the flower itself is also red. For we’ve shown (or in the example, assumed) that red
just is a kind of product of the world’s interaction with the mind, and not the sort of thing
that the world could have on its own.
2. Or take “friendship” as a relational property, one that only has being in relationship
between you and me. What kind of sense would it make to ask whether you, alone, can
have the friendship?
3. Likewise, K has shown us that S&T must be intuitions, or forms of intuition. What
sense does it then make to suggest that they are also, somehow, out there in the objects?
B. A follow-up objection: Doesn’t this violate Kant’s own proscription on knowledge about
1. Answer: No, because it turns out that the prohibition is against positive knowledge
about particular things-in-themselves, that they have certain properties for instance. Very
general and negative ascriptions to things in themselves—negative knowledge, if you
will, is permitted. And the way Kant justifies his claim to such knowledge is through an
analysis not of the things-in-themselves, but of the nature of our cognition.
C. Another version: Okay, why can’t space and time be subjective forms of our intuition but the
objects in themselves have some similar or isomorphic set of properties?
1. Answer: What would it be for things-in-themselves to be even similar or
“isomorphic”? What is similar to being simultaneous or successive or to the left of?
Wouldn’t anything similar to these relations just be spatio-temporal relations?
VI. The humiliation of speculative reason
A. Metaphors of discipline, constraint.
By submitting to critique, “one can be spared many difficult and nevertheless fruitless
efforts, since one would not attribute to reason anything which obviously exceeds its
capacity, but would rather subject reason, which does not gladly suffer constraint in the
paroxysms of its lust for speculative expansion, to the discipline of abstinence”
B. But there must still be some purpose behind the speculative interests of reason.
1. Remember that this is supposed to be a natural striving on the part of reason.
2. The three “ideas” in which we are particularly interested: God, freedom of the will, and
the immortality of the soul.
VII. Kant’s Three Questions, and the Possibility of Hope
A. What can I know? This is the discussion of skepticism and the synthetic a priori
which we’ve been discussing so far. Also, know your limits: know that you can’t know anything
dogmatically or mystically about things-in-themselves, including whether freedom is impossible
or whether there is eternal reward and punishment.
B. What should I do? Obey the moral law, which is in effect the effort to “do that through
which you will become worthy to be happy” (B836).
C. What can I hope? The third question is both theoretical and practical: it has to do with what
sorts of entities or states of affairs we can rational “hope for” or “have faith in,” given our various
practical concerns and obligations. K is effectively asking: if I do that which the moral law
prescribes, what may I rationally hope? Kant’s answer: to be made happy in proportion to the
extent to which you have made yourself happy.
*We will the “highest good”—not just our own virtue, but the state of affairs in which
our happiness is proportioned to our virtue. A world in which this obtained for everyone
would be a moral world.
*What is implied by such a hope? That God exists, since only a supremely great being
can guarantee that everyone’s happiness is ultimately proportioned to his/her virtue.
And, since this doesn’t happen in this world (as we see empirically) we must, in order to
be fully rational, also hope for (or have faith in) a future life beyond this one, in which
God does guarantee that this happens.