Kant, Problems of the 1st Critique

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A History of Philosophy
Volume VI, Part III: Immanuel Kant
Frederick Copleston, S.J.
Chapter XI: The Problems of the First Critique
A. The General Problem of Metaphysics
1. Kant places an obvious emphasis on the problem of metaphysics (prefaces to Critique of Pure
Reason and Prolegomena)
a. Is metaphysics possible or not? – Is it capable of extending our knowledge of reality?
b. For Kant, the chief problems of metaphysics are God, freedom and immortality.
c. Is metaphysics capable of giving us sure knowledge of the existence and nature of God, of
human freedom, and of the existence in man of a spiritual and immortal soul? (211b)
2. Such a question clearly presupposed doubt, and Kant believes there is abundant reason for such
doubt
a. “Time was when metaphysics ‘was called the queen of all the sciences; and if one takes the
will for the deed, she certainly deserved this title of honour on account of the outstanding
importance of her subject-matter’” (211c) – Kant seems to raise a valid claim – a field should
not be judged by that which it studies.
3. Kant never denied the importance of the main themes with which metaphysics treats.
a. But now, he observes, metaphysics has fallen into disrepute (212a)
b. Understandable – math and the natural sciences have advanced, and there is in these fields a
great area of generally accepted knowledge, while metaphysics appears to be an arena for
endless disputes
c. Kant says that metaphysics cannot provide its objects by the principles of pure reason, unlike
Euclid’s geometry can
d. “The fact of the matter is that metaphysics, unlike physics, has not found any sure scientific
method the application of which will enable it to solve its problems” ~ Copleston (212b)
i. This leads us to ask “why is it that here no sure path of science has yet been found? Is it
perhaps impossible to find one?” ~ Kant
4. “The inconclusiveness of metaphysics, its inability hitherto to find a reliable method which will
lead to certain conclusions, its constant tendency to retrace its steps and to start all over again;
such characteristics have helped to produce a widespread indifference towards metaphysics and
its claims” (212c)
a. In one sense this indifference is unjustified – it’s objects are not a matter of indifference to
human nature
b. At the same time, in Kant’s view, this indifference is an expression of a contemporary
maturity of judgment which refuses to be satisfied with illusory knowledge or pseudo-science
- stimulus to undertake a critical investigation of metaphysics (212d)
5. What metaphysics means for Kant
a. Disagreed with Locke’s theory that all our concepts are ultimately derived from experience
b. Also disagrees with opposite theory of innate ideas (212e)
c. Believed there are concepts and principles which the reason derives from within itself on the
occasion of experience – it is an a priori concept in the sense that it is not derived from
experience but is applied to and in a sense governs experience (213a)
i. There are, therefore, a priori concepts and principles which are grounded in the mind’s
own structure
ii. These concepts are ‘pure’ in the sense that they are, of themselves, empty of all empirical
content or material
Copleston’s History of Philosophy, Ch XI
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d. Kant observes that metaphysicians then assumed that reason can apply these concepts and
principles so as to apprehend supersensible realities and thing-in-themselves, not just as they
appear to us (213b) question – revolution of reason
i. And this is how the various systems of dogmatic metaphysics have arisen
ii. This assumption was imprudent – “We cannot take it for granted that the a priori
concepts and principles of the reason can be used to transcend experience; that is to know
realities which are not given in experience” (213c)
e. Therefore, Kant says we must first undertake a critical investigation into the powers of pure
reason itself, which is the task dogmatic philosophers neglected
The question for Kant is: “What and how much can understanding and reason know, apart from
all experience?’ (213d)
a. For Kant, metaphysics is a non-empirical science which claims to transcend experience,
attaining to a knowledge of purely intelligible realities by means of a priori concepts and
principles (213e)
b. Given this view, the validity of metaphysics’ claim obviously is determined the answer to
Kant’s question, what and how much the mind can know apart from experience.
c. For Kant, this requires an inquiry into the faculty of pure reason
i. He is concerned with the pure conditions in the human subject as such for knowing
objects (214a)
What are these conditions?
a. There are empirical conditions for perceiving things and for learning truths, but Kant is not
concerned with these
i. Objective – light for vision (214b)
ii. Subjective – conditions on the part of the knowing subject himself; e.g. disease of the eye
or varying degrees in the ability to understand
b. Kant is concerned with the ‘pure’ conditions of human knowledge as such
i. With the formal elements of pure consciousness; the necessary conditions for knowing
objects
ii. If the conditions turn out to be such that realities transcending sense-experience cannot be
objects of knowledge, the claims of speculative metaphysics will have been shown to be
hollow and vain (214d)
“Kant’s field of inquiry may be too narrow in its starting-point, in the sense that metaphysics
means for him a particular type of metaphysics [the Leibniz-Wolffian system]; but the inquiry is
developed in such a way that the conclusions arrived at have a very wide range of application.”
(215c)
It is important to not that Kant does not always use the term ‘metaphysics’ in the same sense
(215c-216c)
a. E.g. – Metaphysics as a natural disposition is actual and therefore obviously possible  the
mind has a natural tendency to raise such problems as those of God and immortality
b. But metaphysics as a science (if we mean by this a scientific knowledge of supersensible
beings) has never, according to Kant, been a reality
B. The Problem of a priori Knowledge
1. The possibility of metaphysics as a science is for Kant an important problem, but is only part of
the general problem dealt with in the Critique of Pure Reason: the possibility of a priori
knowledge (216d)
2. Kant does not mean knowledge which is relatively a priori – antecedent knowledge a priori only
in relation to a particular experience
a. Kant is thinking of knowledge which is a priori in relation to all experience.
3. Kant is not thinking of innate ideas
Copleston’s History of Philosophy, Ch XI
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a. Pure a priori knowledge does not mean knowledge which is explicitly present in the mind
before it has begun to experience anything at all: it means knowledge which is underived
from experience (217b)
b. “That our knowledge begins with experience there can be no doubt…But though all our
knowledge begins with experience, it does not follow that it all arises out of experience” ~
Kant
c. Our knowledge must begin with experience b/c the cognitive faculty requires to be brought
into exercise by our sense beings affected by objects – given sensations, the raw material of
experience, the mind can set to work (217cd)
4. Why should Kant think that it is possible for there to be any a priori knowledge at all?
a. Agreed with Hume – we cannot derive necessity and strict universality from
experience
b. Therefore, ‘necessity and strict universality are sure marks of a priori knowledge and are
inseparably connected with one another’ (217e)
c. And it is easy to show that we possess such knowledge – e.g. mathematics
5. For Kant, although Hume was right in saying that a necessary relation between event and cause is
not given in experience, his psychological explanation of its origin in terms of the association of
ideas was inadequate
a. To say that every event must have a cause is not simply the expression of an habitual
expectation mechanically produced by the association of ideas
b. This necessity is not ‘purely subjective’ – the dependence of any event on a cause is known,
and it is known a priori.
c. My judgment is not simply a generalization from my experience of particular cases and it
does not stand in need of experiential confirmation before its truth can be known
d. This necessity is just on instance of a priori knowledge
6. In the case of those fields where, Kant is convinced, there evidently is a priori knowledge, the
question is not whether this knowledge is possible but rather, how it is possible
7. In the case of speculative metaphysics, Kant says we must ask whether it is possible, rather than
how (219b)
a. If metaphysics provides us with knowledge of God or of immortality, such knowledge must,
on Kant’s view of metaphysics, be a priori, but is it capable in principle of doing so?
C. The Divisions of This Problem
1. Analytic judgments: Those in which the predicate is contained in the concept of the subject
(219c)
a. The predicate does not add to the concept of the subject anything which is not already
contained it, explicitly or implicitly
b. The truth of such judgments depends on the law of contradiction – you cannot deny the
proposition without involving yourself in logical contradiction
2. Synthetic judgments: affirm or deny of a subject a predicate which is not contained in the concept
of the subject (219c)
a. They add something to the concept of the subject
b. A connection is affirmed between predicate and subject, but the predicate cannot be got out
of the subject by mere analysis
c. This connection may be purely factual and contingent: it is then given only in and through
experience and thus the judgment is synthetic a posteriori
i. Such judgments are not strictly universal, but rather assumed and comparative universal
judgments (220b)
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3. Synthetic a priori judgments: the connection between predicate and subject, though not
comparable by mere analysis of the concept of the subject, is none the less necessary and strictly
universal. (220c)
a. Kant’s example: “Everything which happens has its cause”
b. Having a cause is not contained in the concept of an event (synthetic) but at the same time it
is a priori b/c every event, without any possible exception, will have a cause – strictly
universal.
c. It is not simply reasonable to expect, due to pas experience, that all future events will have
causes – it is necessary (220d)
d. In one sense, the proposition is dependent on experience in that we become acquainted with
things happening via experience. But the connection between predicate and subject is given a
priori – not an induction, nor is it in need of experiential confirmation
4. Kant’s synthetic a priori judgments are widely challenged by modern logicians, especially by
empiricists and positivists (221b)
a. For them, all synthetic propositions are a posteriori
b. Only 2 classes of propositions: analytic on the one hand and empirical (synthetic a posteriori)
on the other
5. Where are synthetic a priori judgments found?
a. Mathematics and pure geometry, in the first place (221e)
i. 7 + 5 = 12  The concept of 12 is not obtained by mere analysis of the idea of the union
between 5 and 7…therefore synthetic (222ab)
ii. We need intuition in order to arrive at the notion of 12
b. Physics
i. The question in both is this: How is pure mathematical/natural science possible b/c we
certainly do know such truths a priori.
c. Morals
6. Now we arrive at metaphysics and find that it does not aim simply at analyzing concepts – it
aims at extending our knowledge of reality (223c)
a. Therefore, its propositions must be synthetic
b. They must also be a priori if it is not (and it is not) an empirical science
c. Therefore, if metaphysics is possible, it must consist of synthetic a priori propositions (223c)
d. “And so metaphysics, according to its aim at least, consists simply of synthetic a priori
propositions” ~ Kant
7. However, the claim of metaphysics to be a science is in doubt and therefore, the question is not so
much how but whether metaphysics as a science is possible
a. Important to distinguish between metaphysics as a natural disposition and as a science
b. Kant believes that the human reason is naturally impelled to raise problems which cannot be
answered empirically – here he can ask how (223e)
i. C.S. Lewis – long for something that cannot be satisfied on earth, therefore God,
immortality, etc.
c. As a natural science, he must ask whether
d. How is metaphysics, considered as a natural disposition, possible?
e. Is metaphysics, considered as a science, possible? (224a)
D. Kant’s Copernican Revolution
1. It would be very difficult for Kant to maintain that knowledge consists simply in the conformity
of the mind to its object
a. If, to know objects, the mind must conform itself to them and;
b. If at the same time it cannot find in these objects – considered as empirically given –
necessary connections (224b)
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c. Then it becomes impossible to explain how we can make necessary and strictly universal
judgments which are as a matter of fact verified and which must always be verified
2. Kant’s hypothesis: “Let us try, then, whether we may not make better progress in the tasks of
metaphysics if we assume that objects must conform to our knowledge” (224d)
a. This hypothesis, Kant observes, is analogous to that proposed by Copernicus (224e)
b. For Copernicus, the immediate phenomena would be the same whether the sun revolved
around the earth or vice versa (both make the sun appear to move across the earth from East
to West)
c. The question is whether there are not astronomical phenomena which can only be (or are
better) explained on the heliocentric hypothesis (225a)
d. Kant suggests then that empirical reality would remain what it is even on the hypothesis that
for objects to be known they must conform to our mind rather than the other way around
e. And if a priori knowledge can be explained on the new but no on the old hypothesis, this
obviously favors the former.
3. Kant’s Copernican revolution does not imply the view that reality can be reduced to the human
mind and its ideas (225b)
a. If we assume that the human mind is purely passive in knowledge, we cannot explain the a
priori knowledge which we undoubtedly possess (225c)
b. Therefore, the mind is active.
c. But this activity does not mean creation of beings out of nothing
d. It means, rather, that the mind imposes its own forms of cognition on the ultimate material of
experience.
i. Things can only be known through these forms
e. Things-in-themselves are not determined by the human mind.
f. Never able to see things in themselves, but able to understand why they appear as they do –
know why the empirical world is what it is for his consciousness (226e-227a)
4. For Kant, we know that every event must have a cause (228b)
a. And this is an instance of a priori cognition
b. And it is possible only on condition that objects, to be objects (that is, to be known), must be
subjected to the a priori concepts or categories of the human understanding, of which
causality is one
c. Nothing will ever enter the field of our experience except as exemplifying the causal relation
E. Sensibility, Understanding, Reason and the Structure of the First Critique
1. There are 2 sources of human knowledge: sensibility and knowledge (229b)
a. Objects are given to us through sense and thought through the understanding
2. The given is the synthesis of form and matter, the form being imposed by human sensibility
a. Things in themselves are never given to us as objects: that which the understanding finds
before it as the given is already a synthesis of form and matter (229d)
b. The understanding then further synthesizes the data of sense intuition under its own pure
(non-empirical) concepts or categories.
3. The contributions of sensibility and understanding are distinguishable
a. The function of the pure concepts or categories of the understanding is to synthesize the data
of sense intuition
b. They are therefore inapplicable to realities which are not, and cannot be, given in senseexperience (230a)
c. Therefore, no metaphysics which consists in using the pure concepts or categories of the
understanding (e.g. concepts of cause and substance) to transcend experience, as Kant puts it,
and to describe supersensible reality can legitimately claim to be a science
4. Transcendental Ideas: transcend experience in the sense that on objects are given, or can be given,
within experience which correspond to them (230c)
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a. E.g., God
b. Kant ascribes them to reason (230d)
c. Reason refers to the human intellect as seeking to unify a manifold referring it to an
unconditioned principle, such as God
d. This is a natural tendency of the reason, and Kant does not belittle it (230e)
e. They serve as kind of ideal goals
5. The question arises: Do these Ideas possess more than a regulative function? (231a)
a. Kant does not believe they can be the source of a theoretical knowledge of corresponding
realities
b. Any attempt to use these Ideas as the basis for metaphysics as a science is foredoomed to
failure
c. Given our possession of these Ideas, it is easy to understand the temptation to use them in a
transcendent way – to extend our theoretical knowledge beyond the field of experience (231c)
6. Kant affirms the value of metaphysics considered as a natural disposition but denies its claim to
constitute a true science which gives us theoretical knowledge of purely intelligible reality (231e)
F. The Significance of the 1st Critique in the Context of the General Problem of Kant’s Philosophy
1. In Dreams of a Ghost-Seer, Kant declared that metaphysics sets the limits of the boundaries of
theoretical or scientific knowledge (232d)
a. Supersensible reality is not an object of theoretical knowledge
b. This delimitation does not show that God, e.g., is unthinkable or that the term is meaningless
c. What it does is to put freedom, immortality and God beyond the range of either proof or
disproof
d. Thus, the criticism of metaphysics (found in the Transcendental Dialectic) opens the way for
practical or moral faith, resting on the moral consciousness (232e-233a)
2. Thus, Kant can say that he has to do away with knowledge to make room for faith and that his
destructive criticism of metaphysics’ claim to be a science strikes a blow at the root of
materialism, fatalism and atheism.
a. Now truths (e.g. God exists) no longer rest on fallacious arguments which afford a ground for
those who deny these truths
b. They are moved to the sphere of the practical or moral reason and become objects of faith
rather than of knowledge (this term being taken in a sense analogous to that in which it is
used with reference to mathematics and natural science) (233b)
3. It is a great mistake to look at this as a mere bribe to the devout or as a mere act of prudence on
Kant’s part (233c)
a. It is a part of his solution to the great problem of reconciling the world of science, on the one
hand, with, on the other, the world of the moral and religious consciousness
b. There is no valid reason whatsoever for saying that the limits of our scientific or theoretical
knowledge (limits determined by the a priori forms of human sensibility and understanding)
are identical with the limits of reality
c. And the moral consciousness, when its practical implications are developed, takes us beyond
the sensible sphere
d. Even though we cannot demonstrate scientifically that man is free, belief in freedom is
demanded by the moral consciousness (233d)
4. Difficulties
a. Division between sensible, phenomenal reality and noumenal, purely intelligible reality
b. Difficult conception of man as phenomenally determined but noumenally free, as determined
and free at the same time (233e)
5. The conclusions of the 1st Critique form only a part of the solution to a general problem – that of
the reconciliation of the world of Newtonian physics with the world of reality and religion –
which underlies all Kant’s thinking
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