delay to the doctrinal [part] in order to profit, as far as is
possible, by the more favourable moments of my increasing years. It is
obvious that in this [part] there will be no special section for the
Judgement, because in respect of this faculty Criticism serves instead
of Theory; but, according to the division of Philosophy (and also of
pure Philosophy) into theoretical and practical, the Metaphysic of
Nature and of Morals will complete the undertaking.
INTRODUCTION
I. OF THE DIVISION OF PHILOSOPHY
We proceed quite correctly if, as usual, we divide Philosophy, as
containing the principles of the rational cognition of things by means
of concepts (not merely, as logic does, principles of the form of
thought in general without distinction of Objects), into _theoretical_
and _practical_. But then the concepts, which furnish their Object
to the principles of this rational cognition, must be specifically
distinct; otherwise they would not justify a division, which always
presupposes a contrast between the principles of the rational cognition
belonging to the different parts of a science.
Now there are only two kinds of concepts, and these admit as many
distinct principles of the possibility of their objects, viz. _natural
concepts_ and the _concept of freedom_. The former render possible
_theoretical_ cognition according to principles _a priori_; the latter
in respect of this theoretical cognition only supplies in itself a
negative principle (that of mere contrast), but on the other hand it
furnishes fundamental propositions which extend the sphere of the
determination of the will and are therefore called practical. Thus
Philosophy is correctly divided into two parts, quite distinct in
their principles; the theoretical part or _Natural Philosophy_, and
the practical part or _Moral Philosophy_ (for that is the name given
to the practical legislation of Reason in accordance with the concept
of freedom). But up to the present a gross misuse of these expressions
has prevailed, both in the division of the different principles and
consequently also of Philosophy itself. For what is practical according
to natural concepts has been identified with the practical according
to the concept of freedom; and so with the like titles, ‘theoretical’
and ‘practical’ Philosophy, a division has been made, by which in
fact nothing has been divided (for both parts might in such case have
principles of the same kind).
The will, regarded as the faculty of desire, is (in this view) one
of the many natural causes in the world, viz. that cause which acts
in accordance with concepts. All that is represented as possible (or
necessary) by means of a will is called practically possible (or
necessary); as distinguished from the physical possibility or necessity
of an effect, whose cause is not determined to causality by concepts
(but in lifeless matter by mechanism and in animals by instinct).
Here, in respect of the practical, it is left undetermined whether the
concept which gives the rule to the causality of the will, is a natural
concept or a concept of freedom.
But the last distinction is essential. For if the concept which
determines the causality is a natural concept, then the principles are
_technically practical_; whereas, if it is a concept of freedom they
are _morally practical_. And as the division of a rational science
depends on the distinction between objects whose cognition needs
distinct principles, the former will belong to theoretical Philosophy
(doctrine of Nature), but the latter alone will constitute the second
part, viz. practical Philosophy (doctrine of Morals).
All technically practical rules (_i.e._ the rules of art and skill
generally, or of prudence regarded as skill in exercising an influence
over men and their wills), so far as their principles rest on concepts,
must be reckoned only as corollaries to theoretical Philosophy. For
they concern only the possibility of things according to natural
concepts, to which belong not only the means which are to be met
with in nature, but also the will itself (as a faculty of desire
and consequently a natural faculty), so far as it can be determined
conformably to these rules by natural motives. However, practical
rules of this kind are not called laws (like physical laws), but only
precepts; because the will does not stand merely under the natural
concept, but also under the concept of freedom, in relation to which
its principles are called laws. These with their consequences alone
constitute the second or practical part of Philosophy.
The solution of the problems of pure geometry does not belong to a
particular part of the science; mensuration does not deserve the
name of practical, in contrast to pure, geometry, as a second part
of geometry in general; and just as little ought the mechanical
or chemical art of experiment or observation to be reckoned as a
practical part of the doctrine of Nature. Just as little, in fine,
ought housekeeping, farming, statesmanship, the art of conversation,
the prescribing of diet, the universal doctrine of happiness itself,
or the curbing of the inclinations and checking of the affections
for the sake of happiness, to be reckoned as practical Philosophy,
or taken to constitute the second part of Philosophy in general.
For all these contain only rules of skill (and are consequently only
technically practical) for bringing about an effect that is possible
according to the natural concepts of causes and effects, which, since
they belong to theoretical Philosophy, are subject to those precepts
as mere corollaries from it (viz. natural science), and can therefore
claim no place in a special Philosophy called practical. On the other
hand, the morally practical precepts, which are altogether based on the
concept of freedom to the complete exclusion of the natural determining
grounds of the will, constitute a quite special class. These, like the
rules which nature obeys, are called simply laws, but they do not, like
them, rest on sensuous conditions but on a supersensible principle;
and accordingly they require for themselves a quite different part of
Philosophy, called practical, corresponding to its theoretical part.
We hence see that a complex of practical precepts given by Philosophy
does not constitute a distinct part of Philosophy, as opposed to the
theoretical part, because these precepts are practical; for they might
be that, even if their principles were derived altogether from the
theoretical cognition of nature (as technically practical rules). [A
distinct branch of Philosophy is constituted only] if their principle,
as it is not borrowed from the natural concept, which is always
sensuously conditioned, rests on the supersensible, which alone makes
the concept of freedom cognisable by formal laws. These precepts are
then morally practical, _i.e._ not merely precepts or rules in this
or that aspect, but, without any preceding reference to purposes and
designs, are laws.
II. OF THE REALM OF PHILOSOPHY IN GENERAL
So far as our concepts have _a priori_ application, so far extends
the use of our cognitive faculty according to principles, and with it
Philosophy.
But the complex of all objects, to which those concepts are referred,
in order to bring about a knowledge of them where it is possible,
may be subdivided according to the adequacy or inadequacy of our
[cognitive] faculty to this design.
Concepts, so far as they are referred to objects, independently of the
possibility or impossibility of the cognition of these objects, have
their field which is determined merely according to the relation that
their Object has to our cognitive faculty in general. The part of this
field in which knowledge is possible for us is a ground or territory
(_territorium_) for these concepts and the requisite cognitive faculty.
The part of this territory, where they are legislative, is the realm
(_ditio_) of these concepts and of the corresponding cognitive
faculties. Empirical concepts have, therefore, their territory in
nature, as the complex of all objects of sense, but no realm, only
a dwelling-place (_domicilium_); for though they are produced in
conformity to law they are not legislative, but the rules based on them
are empirical and consequently contingent.
Our whole cognitive faculty has two realms, that of natural concepts
and that of the concept of freedom; for through both it is legislative
_a priori_. In accordance with this, Philosophy is divided into
theoretical and practical. But the territory to which its realm extends
and in which its legislation is _exercised_, is always only the complex
of objects of all possible experience, so long as they are taken for
nothing more than mere phenomena; for otherwise no legislation of the
Understanding in respect of them is conceivable.
Legislation through natural concepts is carried on by means of the
Understanding and is theoretical. Legislation through the concept of
freedom is carried on by the Reason and is merely practical. It is
only in the practical [sphere] that the Reason can be legislative;
in respect of theoretical cognition (of nature) it can merely (as
acquainted with law by the Understanding) deduce from given laws
consequences which always remain within [the limits of] nature. But on
the other hand, Reason is not always therefore _legislative_, where
there are practical rules, for they may be only technically practical.
Understanding and Reason exercise, therefore, two distinct legislations
in regard to one and the same territory of experience, without
prejudice to each other. The concept of freedom as little disturbs
the legislation of nature, as the natural concept influences the
legislation through the former.--The possibility of at least thinking
without contradiction the co-existence of both legislations, and of
the corresponding faculties in the same subject, has been shown in the
Critique of pure Reason; for it annulled the objections on the other
side by exposing the dialectical illusion which they contain.
These two different realms then do not limit each other in their
legislation, though they perpetually do so in the world of sense.
That they do not constitute _one_ realm, arises from this, that the
natural concept represents its objects in intuition, not as things
in themselves, but as mere phenomena; the concept of freedom, on the
other hand, represents in its Object a thing in itself, but not in
intuition. Hence, neither of them can furnish a theoretical knowledge
of its Object (or even of the thinking subject) as a thing in itself;
this would be the supersensible, the Idea of which we must indeed make
the basis of the possibility of all these objects of experience, but
which we can never extend or elevate into a cognition.
There is, then, an unbounded but also inaccessible field for our whole
cognitive faculty--the field of the supersensible--wherein we find no
territory, and, therefore, can have in it, for theoretical cognition,
no realm either for concepts of Understanding or Reason. This field we
must indeed occupy with Ideas on behalf of the theoretical as well as
the practical use of Reason, but we can supply to them in reference to
the laws [arising] from the concept of freedom no other than practical
reality, by which our theoretical cognition is not extended in the
slightest degree towards the supersensible.
Now even if an immeasurable gulf is fixed between the sensible realm
of the concept of nature and the supersensible realm of the concept of
freedom, so that no transition is possible from the first to the second
(by means of the theoretical use of Reason), just as if they were two
different worlds of which the first could have no influence upon the
second, yet the second is _meant_ to have an influence upon the first.
The concept of freedom is meant to actualise in the world of sense
the purpose proposed by its laws, and consequently nature must be so
thought that the conformity to law of its form, at least harmonises
with the possibility of the purposes to be effected in it according to
laws of freedom.--There must, therefore, be a ground of the _unity_
of the supersensible, which lies at the basis of nature, with that
which the concept of freedom practically contains; and the concept
of this ground, although it does not attain either theoretically or
practically to a knowledge of the same, and hence has no peculiar
realm, nevertheless makes possible the transition from the mode of
thought according to the principles of the one to that according to the
principles of the other.
III. OF THE CRITIQUE OF JUDGEMENT AS A MEANS OF COMBINING THE TWO PARTS
OF PHILOSOPHY INTO A WHOLE.
The Critique of the cognitive faculties, as regards what they can
furnish _a priori_, has properly speaking no realm in respect of
Objects, because it is not a doctrine, but only has to investigate
whether and how, in accordance with the state of these faculties, a
doctrine is possible by their means. Its field extends to all their
pretensions, in order to confine them within their legitimate bounds.
But what cannot enter into the division of Philosophy may yet enter,
as a chief part, into the Critique of the pure faculty of cognition in
general, viz. if it contains principles which are available neither for
theoretical nor for practical use.
The natural concepts, which contain the ground of all
theoretical knowledge _a priori_, rest on the legislation of the
Understanding.--The concept of freedom, which contains the ground of
all sensuously-unconditioned practical precepts _a priori_, rests on
the legislation of the Reason. Both faculties, therefore, besides being
capable of application as regards their logical form to principles of
whatever origin, have also as regards their content, their special
legislations above which there is no other (_a priori_); and hence the
division of Philosophy into theoretical and practical is justified.
But in the family of the higher cognitive faculties there is a middle
term between the Understanding and the Reason. This is the _Judgement_,
of which we have cause for supposing according to analogy that it
may contain in itself, if not a special legislation, yet a special
principle of its own to be sought according to laws, though merely
subjective _a priori_. This principle, even if it have no field of
objects as its realm, yet may have somewhere a territory with a certain
character, for which no other principle can be valid.
But besides (to judge by analogy) there is a new ground for bringing
the Judgement into connexion with another arrangement of our
representative faculties, which seems to be of even greater importance
than that of its relationship with the family of the cognitive
faculties. For all faculties or capacities of the soul can be reduced
to three, which cannot be any further derived from one common ground:
the _faculty of knowledge_, the _feeling of pleasure and pain_, and the
_faculty of desire_.[9] For the faculty of knowledge the Understanding
is alone legislative, if (as must happen when it is considered by
itself without confusion with the faculty of desire) this faculty is
referred to nature as the faculty of _theoretical knowledge_; for in
respect of nature (as phenomenon) it is alone possible for us to give
laws by means of natural concepts _a priori_, _i.e._ by pure concepts
of Understanding.--For the faculty of desire, as a higher faculty
according to the concept of freedom, the Reason (in which alone this
concept has a place) is alone _a priori_ legislative.--Now between the
faculties of knowledge and desire there is the feeling of pleasure,
just as the Judgement is intermediate between the Understanding and
the Reason. We may therefore suppose provisionally that the Judgement
likewise contains in itself an _a priori_ principle. And as pleasure
or pain is necessarily combined with the faculty of desire (either
preceding this principle as in the lower desires, or following it as
in the higher, when the desire is determined by the moral law), we may
also suppose that the Judgement will bring about a transition from the
pure faculty of knowledge, the realm of natural concepts, to the realm
of the concept of freedom, just as in its logical use it makes possible
the transition from Understanding to Reason.
Although, then, Philosophy can be divided only into two main parts,
the theoretical and the practical, and although all that we may be
able to say of the special principles of Judgement must be counted as
belonging in it to the theoretical part, _i.e._ to rational cognition
in accordance with natural concepts; yet the Critique of pure Reason,
which must decide all this, as regards the possibility of the system
before undertaking it, consists of three parts; the Critique of pure
Understanding, of pure Judgement, and of pure Reason, which faculties
are called pure because they are legislative _a priori_.
IV. OF JUDGEMENT AS A FACULTY LEGISLATING _A PRIORI_
Judgement in general is the faculty of thinking the particular as
contained under the Universal. If the universal (the rule, the
principle, the law) be given, the Judgement which subsumes the
particular under it (even if, as transcendental Judgement, it furnishes
_a priori_, the conditions in conformity with which subsumption under
that universal is alone possible) is _determinant_. But if only the
particular be given for which the universal has to be found, the
Judgement is merely _reflective_.
The determinant Judgement only subsumes under universal transcendental
laws given by the Understanding; the law is marked out for it, _a
priori_, and it has therefore no need to seek a law for itself in
order to be able to subordinate the particular in nature to the
universal.--But the forms of nature are so manifold, and there
are so many modifications of the universal transcendental natural
concepts left undetermined by the laws given, _a priori_, by the pure
Understanding,--because these only concern the possibility of a nature
in general (as an object of sense),--that there must be laws for these
[forms] also. These, as empirical, may be contingent from the point
of view of _our_ Understanding, and yet, if they are to be called
laws (as the concept of a nature requires), they must be regarded as
necessary in virtue of a principle of the unity of the manifold, though
it be unknown to us.--The reflective Judgement, which is obliged to
ascend from the particular in nature to the universal, requires on that
account a principle that it cannot borrow from experience, because its
function is to establish the unity of all empirical principles under
higher ones, and hence to establish the possibility of their systematic
subordination. Such a transcendental principle, then, the reflective
Judgement can only give as a law from and to itself. It cannot derive
it from outside (because then it would be the determinant Judgement);
nor can it prescribe it to nature, because reflection upon the laws
of nature adjusts itself by nature, and not nature by the conditions
according to which we attempt to arrive at a concept of it which is
quite contingent in respect of these.
This principle can be no other than the following: As universal laws
of nature have their ground in our Understanding, which prescribes
them to nature (although only according to the universal concept of
it as nature); so particular empirical laws, in respect of what is in
them left undetermined by these universal laws, must be considered in
accordance with such a unity as they would have if an Understanding
(although not our Understanding) had furnished them to our cognitive
faculties, so as to make possible a system of experience according
to particular laws of nature. Not as if, in this way, such an
Understanding must be assumed as actual (for it is only our reflective
Judgement to which this Idea serves as a principle--for reflecting, not
for determining); but this faculty thus gives a law only to itself and
not to nature.
Now the concept of an Object, so far as it contains the ground of
the actuality of this Object, is the _purpose_; and the agreement
of a thing with that constitution of things, which is only possible
according to purposes, is called the _purposiveness_ of its form. Thus
the principle of Judgement, in respect of the form of things of nature
under empirical laws generally, is the _purposiveness of nature_ in its
manifoldness. That is, nature is represented by means of this concept,
as if an Understanding contained the ground of the unity of the
manifold of its empirical laws.
The purposiveness of nature is therefore a particular concept, _a
priori_, which has its origin solely in the reflective Judgement. For
we cannot ascribe to natural products anything like a reference of
nature in them to purposes; we can only use this concept to reflect
upon such products in respect of the connexion of phenomena which is
given in nature according to empirical laws. This concept is also quite
different from practical purposiveness (in human art or in morals),
though it is certainly thought according to the analogy of these last.
V. THE PRINCIPLE OF THE FORMAL PURPOSIVENESS OF NATURE IS A
TRANSCENDENTAL PRINCIPLE OF JUDGEMENT.
A transcendental principle is one by means of which is represented, _a
priori_, the universal condition under which alone things can be in
general Objects of our cognition. On the other hand, a principle is
called metaphysical if it represents the _a priori_ condition under
which alone Objects, whose concept must be empirically given, can be
further determined _a priori_. Thus the principle of the cognition of
bodies as substances, and as changeable substances, is transcendental,
if thereby it is asserted that their changes must have a cause; it is
metaphysical if it asserts that their changes must have an _external_
cause. For in the former case bodies need only be thought by means
of ontological predicates (pure concepts of Understanding), _e.g._
substance, in order to cognise the proposition _a priori_; but in
the latter case the empirical concept of a body (as a movable thing
in space) must lie at the basis of the proposition, although once
this basis has been laid down, it may be seen completely _a priori_
that this latter predicate (motion only by external causes) belongs
to body.--Thus, as I shall presently show, the principle of the
purposiveness of nature (in the manifoldness of its empirical laws) is
a transcendental principle. For the concept of Objects, so far as they
are thought as standing under this principle, is only the pure concept
of objects of possible empirical cognition in general and contains
nothing empirical. On the other hand, the principle of practical
purposiveness, which must be thought in the Idea of the _determination_
of a free _will_, is a metaphysical principle; because the concept of a
faculty of desire as a will must be given empirically (_i.e._ does not
belong to transcendental predicates). Both principles are, however, not
empirical, but _a priori_; because for the combination of the predicate
with the empirical concept of the subject of their judgements no
further experience is needed, but it can be apprehended completely _a
priori_.