No More Learning

I apply it,
therefore, to the present case, and ask whether it could take the form
of a law, and consequently whether I can by my maxim at the same
time give such a law as this, that everyone may deny a deposit of
which no one can produce a proof. I at once become aware that such a
principle, viewed as a law, would annihilate itself, because the
result would be that there would be no deposits. A practical law which
I recognise as such must be qualified for universal legislation;
this is an identical proposition and, therefore, self-evident. Now, if
I say that my will is subject to a practical law, I cannot adduce my
inclination (e. g. , in the present case my avarice) as a principle of
determination fitted to be a universal practical law; for this is so
far from being fitted for a universal legislation that, if put in
the form of a universal law, it would destroy itself.

{BOOK_1|CHAPTER_1 ^paragraph 50}

It is, therefore, surprising that intelligent men could have thought
of calling the desire of happiness a universal practical law on the
ground that the desire is universal, and, therefore, also the maxim by
which everyone makes this desire determine his will. For whereas in
other cases a universal law of nature makes everything harmonious;
here, on the contrary, if we attribute to the maxim the universality
of a law, the extreme opposite of harmony will follow, the greatest
opposition and the complete destruction of the maxim itself and its
purpose. For, in that case, the will of all has not one and the same
object, but everyone has his own (his private welfare), which may
accidentally accord with the purposes of others which are equally
selfish, but it is far from sufficing for a law; because the
occasional exceptions which one is permitted to make are endless,
and cannot be definitely embraced in one universal rule. In this
manner, then, results a harmony like that which a certain satirical
poem depicts as existing between a married couple bent on going to
ruin, "O, marvellous harmony, what he wishes, she wishes also"; or
like what is said of the pledge of Francis I to the Emperor Charles V,
"What my brother Charles wishes that I wish also" (viz. , Milan).
Empirical principles of determination are not fit for any universal
external legislation, but just as little for internal; for each man
makes his own subject the foundation of his inclination, and in the
same subject sometimes one inclination, sometimes another, has the
preponderance. To discover a law which would govern them all under
this condition, namely, bringing them all into harmony, is quite
impossible.



V. PROBLEM I.



Supposing that the mere legislative form of maxims is alone the
sufficient determining principle of a will, to find the nature of
the will which can be determined by it alone.

{BOOK_1|CHAPTER_1 ^paragraph 55}

Since the bare form of the law can only be conceived by reason, and
is, therefore, not an object of the senses, and consequently does
not belong to the class of phenomena, it follows that the idea of
it, which determines the will, is distinct from all the principles
that determine events in nature according to the law of causality,
because in their case the determining principles must themselves be
phenomena. Now, if no other determining principle can serve as a law
for the will except that universal legislative form, such a will
must be conceived as quite independent of the natural law of phenomena
in their mutual relation, namely, the law of causality; such
independence is called freedom in the strictest, that is, in the
transcendental, sense; consequently, a will which can have its law
in nothing but the mere legislative form of the maxim is a free will.



VI. PROBLEM II.



Supposing that a will is free, to find the law which alone is
competent to determine it necessarily.

{BOOK_1|CHAPTER_1 ^paragraph 60}

Since the matter of the practical law, i. e. , an object of the maxim,
can never be given otherwise than empirically, and the free will is
independent on empirical conditions (that is, conditions belonging
to the world of sense) and yet is determinable, consequently a free
will must find its principle of determination in the law, and yet
independently of the matter of the law. But, besides the matter of the
law, nothing is contained in it except the legislative form. It is the
legislative form, then, contained in the maxim, which can alone
constitute a principle of determination of the [free] will.



REMARK.



Thus freedom and an unconditional practical law reciprocally imply
each other. Now I do not ask here whether they are in fact distinct,
or whether an unconditioned law is not rather merely the consciousness
of a pure practical reason and the latter identical with the
positive concept of freedom; I only ask, whence begins our knowledge
of the unconditionally practical, whether it is from freedom or from
the practical law? Now it cannot begin from freedom, for of this we
cannot be immediately conscious, since the first concept of it is
negative; nor can we infer it from experience, for experience gives us
the knowledge only of the law of phenomena, and hence of the mechanism
of nature, the direct opposite of freedom. It is therefore the moral
law, of which we become directly conscious (as soon as we trace for
ourselves maxims of the will), that first presents itself to us, and
leads directly to the concept of freedom, inasmuch as reason
presents it as a principle of determination not to be outweighed by
any sensible conditions, nay, wholly independent of them. But how is
the consciousness, of that moral law possible? We can become conscious
of pure practical laws just as we are conscious of pure theoretical
principles, by attending to the necessity with which reason prescribes
them and to the elimination of all empirical conditions, which it
directs. The concept of a pure will arises out of the former, as
that of a pure understanding arises out of the latter. That this is
the true subordination of our concepts, and that it is morality that
first discovers to us the notion of freedom, hence that it is
practical reason which, with this concept, first proposes to
speculative reason the most insoluble problem, thereby placing it in
the greatest perplexity, is evident from the following
consideration: Since nothing in phenomena can be explained by the
concept of freedom, but the mechanism of nature must constitute the
only clue; moreover, when pure reason tries to ascend in the series of
causes to the unconditioned, it falls into an antinomy which is
entangled in incomprehensibilities on the one side as much as the
other; whilst the latter (namely, mechanism) is at least useful in the
explanation of phenomena, therefore no one would ever have been so
rash as to introduce freedom into science, had not the moral law,
and with it practical reason, come in and forced this notion upon
us. Experience, however, confirms this order of notions. Suppose
some one asserts of his lustful appetite that, when the desired object
and the opportunity are present, it is quite irresistible. [Ask
him]- if a gallows were erected before the house where he finds this
opportunity, in order that he should be hanged thereon immediately
after the gratification of his lust, whether he could not then control
his passion; we need not be long in doubt what he would reply. Ask
him, however- if his sovereign ordered him, on pain of the same
immediate execution, to bear false witness against an honourable
man, whom the prince might wish to destroy under a plausible
pretext, would he consider it possible in that case to overcome his
love of life, however great it may be. He would perhaps not venture to
affirm whether he would do so or not, but he must unhesitatingly admit
that it is possible to do so. He judges, therefore, that he can do a
certain thing because he is conscious that he ought, and he recognizes
that he is free- a fact which but for the moral law he would never
have known.

{BOOK_1|CHAPTER_1 ^paragraph 65}



VII. FUNDAMENTAL LAW OF THE PURE PRACTICAL REASON.



Act so that the maxim of thy will can always at the same time hold
good as a principle of universal legislation.



{BOOK_1|CHAPTER_1 ^paragraph 70}

REMARK.



Pure geometry has postulates which are practical propositions, but
contain nothing further than the assumption that we can do something
if it is required that we should do it, and these are the only
geometrical propositions that concern actual existence. They are,
then, practical rules under a problematical condition of the will; but
here the rule says: We absolutely must proceed in a certain manner.
The practical rule is, therefore, unconditional, and hence it is
conceived a priori as a categorically practical proposition by which
the will is objectively determined absolutely and immediately (by
the practical rule itself, which thus is in this case a law); for pure
reason practical of itself is here directly legislative. The will is
thought as independent on empirical conditions, and, therefore, as
pure will determined by the mere form of the law, and this principle
of determination is regarded as the supreme condition of all maxims.
The thing is strange enough, and has no parallel in all the rest of
our practical knowledge. For the a priori thought of a possible
universal legislation which is therefore merely problematical, is
unconditionally commanded as a law without borrowing anything from
experience or from any external will. This, however, is not a
precept to do something by which some desired effect can be attained
(for then the will would depend on physical conditions), but a rule
that determines the will a priori only so far as regards the forms
of its maxims; and thus it is at least not impossible to conceive that
a law, which only applies to the subjective form of principles, yet
serves as a principle of determination by means of the objective
form of law in general. We may call the consciousness of this
fundamental law a fact of reason, because we cannot reason it out from
antecedent data of reason, e. g. , the consciousness of freedom (for
this is not antecedently given), but it forces itself on us as a
synthetic a priori proposition, which is not based on any intuition,
either pure or empirical. It would, indeed, be analytical if the
freedom of the will were presupposed, but to presuppose freedom as a
positive concept would require an intellectual intuition, which cannot
here be assumed; however, when we regard this law as given, it must be
observed, in order not to fall into any misconception, that it is
not an empirical fact, but the sole fact of the pure reason, which
thereby announces itself as originally legislative (sic volo, sic
jubeo).



COROLLARY.

{BOOK_1|CHAPTER_1 ^paragraph 75}



Pure reason is practical of itself alone and gives (to man) a
universal law which we call the moral law.



REMARK.



{BOOK_1|CHAPTER_1 ^paragraph 80}

The fact just mentioned is undeniable. It is only necessary to
analyse the judgement that men pass on the lawfulness of their
actions, in order to find that, whatever inclination may say to the
contrary, reason, incorruptible and self-constrained, always
confronts the maxim of the will in any action with the pure will, that
is, with itself, considering itself as a priori practical. Now this
principle of morality, just on account of the universality of the
legislation which makes it the formal supreme determining principle of
the will, without regard to any subjective differences, is declared by
the reason to be a law for all rational beings, in so far as they have
a will, that is, a power to determine their causality by the
conception of rules; and, therefore, so far as they are capable of
acting according to principles, and consequently also according to
practical a priori principles (for these alone have the necessity that
reason requires in a principle). It is, therefore, not limited to
men only, but applies to all finite beings that possess reason and
will; nay, it even includes the Infinite Being as the supreme
intelligence. In the former case, however, the law has the form of
an imperative, because in them, as rational beings, we can suppose a
pure will, but being creatures affected with wants and physical
motives, not a holy will, that is, one which would be incapable of any
maxim conflicting with the moral law. In their case, therefore, the
moral law is an imperative, which commands categorically, because
the law is unconditioned; the relation of such a will to this law is
dependence under the name of obligation, which implies a constraint to
an action, though only by reason and its objective law; and this
action is called duty, because an elective will, subject to
pathological affections (though not determined by them, and,
therefore, still free), implies a wish that arises from subjective
causes and, therefore, may often be opposed to the pure objective
determining principle; whence it requires the moral constraint of a
resistance of the practical reason, which may be called an internal,
but intellectual, compulsion. In the supreme intelligence the elective
will is rightly conceived as incapable of any maxim which could not at
the same time be objectively a law; and the notion of holiness,
which on that account belongs to it, places it, not indeed above all
practical laws, but above all practically restrictive laws, and
consequently above obligation and duty. This holiness of will is,
however, a practical idea, which must necessarily serve as a type to
which finite rational beings can only approximate indefinitely, and
which the pure moral law, which is itself on this account called holy,
constantly and rightly holds before their eyes. The utmost that finite
practical reason can effect is to be certain of this indefinite
progress of one's maxims and of their steady disposition to advance.
This is virtue, and virtue, at least as a naturally acquired
faculty, can never be perfect, because assurance in such a case
never becomes apodeictic certainty and, when it only amounts to
persuasion, is very dangerous.



VIII. THEOREM IV.



The autonomy of the will is the sole principle of all moral laws and
of all duties which conform to them; on the other hand, heteronomy
of the elective will not only cannot be the basis of any obligation,
but is, on the contrary, opposed to the principle thereof and to the
morality of the will.

{BOOK_1|CHAPTER_1 ^paragraph 85}

In fact the sole principle of morality consists in the
independence on all matter of the law (namely, a desired object),
and in the determination of the elective will by the mere universal
legislative form of which its maxim must be capable. Now this
independence is freedom in the negative sense, and this
self-legislation of the pure, and therefore practical, reason is
freedom in the positive sense. Thus the moral law expresses nothing
else than the autonomy of the pure practical reason; that is, freedom;
and this is itself the formal condition of all maxims, and on this
condition only can they agree with the supreme practical law. If
therefore the matter of the volition, which can be nothing else than
the object of a desire that is connected with the law, enters into the
practical law, as the condition of its possibility, there results
heteronomy of the elective will, namely, dependence on the physical
law that we should follow some impulse or inclination. In that case
the will does not give itself the law, but only the precept how
rationally to follow pathological law; and the maxim which, in such
a case, never contains the universally legislative form, not only
produces no obligation, but is itself opposed to the principle of a
pure practical reason and, therefore, also to the moral disposition,
even though the resulting action may be conformable to the law.



REMARK.



Hence a practical precept, which contains a material (and
therefore empirical) condition, must never be reckoned a practical
law. For the law of the pure will, which is free, brings the will into
a sphere quite different from the empirical; and as the necessity
involved in the law is not a physical necessity, it can only consist
in the formal conditions of the possibility of a law in general. All
the matter of practical rules rests on subjective conditions, which
give them only a conditional universality (in case I desire this or
that, what I must do in order to obtain it), and they all turn on
the principle of private happiness. Now, it is indeed undeniable
that every volition must have an object, and therefore a matter; but
it does not follow that this is the determining principle and the
condition of the maxim; for, if it is so, then this cannot be
exhibited in a universally legislative form, since in that case the
expectation of the existence of the object would be the determining
cause of the choice, and the volition must presuppose the dependence
of the faculty of desire on the existence of something; but this
dependence can only be sought in empirical conditions and,
therefore, can never furnish a foundation for a necessary and
universal rule. Thus, the happiness of others may be the object of the
will of a rational being. But if it were the determining principle
of the maxim, we must assume that we find not only a rational
satisfaction in the welfare of others, but also a want such as the
sympathetic disposition in some men occasions. But I cannot assume the
existence of this want in every rational being (not at all in God).
The matter, then, of the maxim may remain, but it must not be the
condition of it, else the maxim could not be fit for a law. Hence, the
mere form of law, which limits the matter, must also be a reason for
adding this matter to the will, not for presupposing it. For
example, let the matter be my own happiness. This (rule), if I
attribute it to everyone (as, in fact, I may, in the case of every
finite being), can become an objective practical law only if I include
the happiness of others. Therefore, the law that we should promote the
happiness of others does not arise from the assumption that this is an
object of everyone's choice, but merely from this, that the form of
universality which reason requires as the condition of giving to a
maxim of self-love the objective validity of a law is the principle
that determines the will. Therefore it was not the object (the
happiness of others) that determined the pure will, but it was the
form of law only, by which I restricted my maxim, founded on
inclination, so as to give it the universality of a law, and thus to
adapt it to the practical reason; and it is this restriction alone,
and not the addition of an external spring, that can give rise to
the notion of the obligation to extend the maxim of my self-love to
the happiness of others.

{BOOK_1|CHAPTER_1 ^paragraph 90}



REMARK II.



The direct opposite of the principle of morality is, when the
principle of private happiness is made the determining principle of
the will, and with this is to be reckoned, as I have shown above,
everything that places the determining principle which is to serve
as a law, anywhere but in the legislative form of the maxim. This
contradiction, however, is not merely logical, like that which would
arise between rules empirically conditioned, if they were raised to
the rank of necessary principles of cognition, but is practical, and
would ruin morality altogether were not the voice of reason in
reference to the will so clear, so irrepressible, so distinctly
audible, even to the commonest men. It can only, indeed, be maintained
in the perplexing speculations of the schools, which are bold enough
to shut their ears against that heavenly voice, in order to support
a theory that costs no trouble.

Suppose that an acquaintance whom you otherwise liked were to
attempt to justify himself to you for having borne false witness,
first by alleging the, in his view, sacred duty of consulting his
own happiness; then by enumerating the advantages which he had
gained thereby, pointing out the prudence he had shown in securing
himself against detection, even by yourself, to whom he now reveals
the secret, only in order that he may be able to deny it at any
time; and suppose he were then to affirm, in all seriousness, that
he has fulfilled a true human duty; you would either laugh in his
face, or shrink back from him with disgust; and yet, if a man has
regulated his principles of action solely with a view to his own
advantage, you would have nothing whatever to object against this mode
of proceeding. Or suppose some one recommends you a man as steward, as
a man to whom you can blindly trust all your affairs; and, in order to
inspire you with confidence, extols him as a prudent man who
thoroughly understands his own interest, and is so indefatigably
active that he lets slip no opportunity of advancing it; lastly,
lest you should be afraid of finding a vulgar selfishness in him,
praises the good taste with which he lives; not seeking his pleasure
in money-making, or in coarse wantonness, but in the enlargement of
his knowledge, in instructive intercourse with a select circle, and
even in relieving the needy; while as to the means (which, of
course, derive all their value from the end), he is not particular,
and is ready to use other people's money for the purpose as if it were
his own, provided only he knows that he can do so safely, and
without discovery; you would either believe that the recommender was
mocking you, or that he had lost his senses. So sharply and clearly
marked are the boundaries of morality and self-love that even the
commonest eye cannot fail to distinguish whether a thing belongs to
the one or the other. The few remarks that follow may appear
superfluous where the truth is so plain, but at least they may serve
to give a little more distinctness to the judgement of common sense.

{BOOK_1|CHAPTER_1 ^paragraph 95}

The principle of happiness may, indeed, furnish maxims, but never
such as would be competent to be laws of the will, even if universal
happiness were made the object. For since the knowledge of this
rests on mere empirical data, since every man's judgement on it
depends very much on his particular point of view, which is itself
moreover very variable, it can supply only general rules, not
universal; that is, it can give rules which on the average will most
frequently fit, but not rules which must hold good always and
necessarily; hence, no practical laws can be founded on it. Just
because in this case an object of choice is the foundation of the rule
and must therefore precede it, the rule can refer to nothing but
what is [felt], and therefore it refers to experience and is founded
on it, and then the variety of judgement must be endless. This
principle, therefore, does not prescribe the same practical rules to
all rational beings, although the rules are all included under a
common title, namely, that of happiness. The moral law, however, is
conceived as objectively necessary, only because it holds for everyone
that has reason and will.

The maxim of self-love (prudence) only advises; the law of
morality commands. Now there is a great difference between that
which we are advised to do and that to which we are obliged.

The commonest intelligence can easily and without hesitation see
what, on the principle of autonomy of the will, requires to be done;
but on supposition of heteronomy of the will, it is hard and
requires knowledge of the world to see what is to be done. That is
to say, what duty is, is plain of itself to everyone; but what is to
bring true durable advantage, such as will extend to the whole of
one's existence, is always veiled in impenetrable obscurity; and
much prudence is required to adapt the practical rule founded on it to
the ends of life, even tolerably, by making proper exceptions. But the
moral law commands the most punctual obedience from everyone; it must,
therefore, not be so difficult to judge what it requires to be done,
that the commonest unpractised understanding, even without worldly
prudence, should fail to apply it rightly.

It is always in everyone's power to satisfy the categorical
command of morality; whereas it is seldom possible, and by no means so
to everyone, to satisfy the empirically conditioned precept of
happiness, even with regard to a single purpose. The reason is that in
the former case there is question only of the maxim, which must be
genuine and pure; but in the latter case there is question also of
one's capacity and physical power to realize a desired object. A
command that everyone should try to make himself happy would be
foolish, for one never commands anyone to do what he of himself
infallibly wishes to do. We must only command the means, or rather
supply them, since he cannot do everything that he wishes. But to
command morality under the name of duty is quite rational; for, in the
first place, not everyone is willing to obey its precepts if they
oppose his inclinations; and as to the means of obeying this law,
these need not in this case be taught, for in this respect whatever he
wishes to do he can do.

He who has lost at play may be vexed at himself and his folly, but
if he is conscious of having cheated at play (although he has gained
thereby), he must despise himself as soon as he compares himself
with the moral law. This must, therefore, be something different
from the principle of private happiness. For a man must have a
different criterion when he is compelled to say to himself: "I am a
worthless fellow, though I have filled my purse"; and when he approves
himself, and says: "I am a prudent man, for I have enriched my
treasure. "

{BOOK_1|CHAPTER_1 ^paragraph 100}

Finally, there is something further in the idea of our practical
reason, which accompanies the transgression of a moral law- namely,
its ill desert. Now the notion of punishment, as such, cannot be
united with that of becoming a partaker of happiness; for although
he who inflicts the punishment may at the same time have the
benevolent purpose of directing this punishment to this end, yet it
must first be justified in itself as punishment, i. e. , as mere harm,
so that if it stopped there, and the person punished could get no
glimpse of kindness hidden behind this harshness, he must yet admit
that justice was done him, and that his reward was perfectly
suitable to his conduct. In every punishment, as such, there must
first be justice, and this constitutes the essence of the notion.
Benevolence may, indeed, be united with it, but the man who has
deserved punishment has not the least reason to reckon upon this.
Punishment, then, is a physical evil, which, though it be not
connected with moral evil as a natural consequence, ought to be
connected with it as a consequence by the principles of a moral
legislation. Now, if every crime, even without regarding the
physical consequence with respect to the actor, is in itself
punishable, that is, forfeits happiness (at least partially), it is
obviously absurd to say that the crime consisted just in this, that he
has drawn punishment on himself, thereby injuring his private
happiness (which, on the principle of self-love, must be the proper
notion of all crime). According to this view, the punishment would
be the reason for calling anything a crime, and justice would, on
the contrary, consist in omitting all punishment, and even
preventing that which naturally follows; for, if this were done, there
would no longer be any evil in the action, since the harm which
otherwise followed it, and on account of which alone the action was
called evil, would now be prevented. To look, however, on all
rewards and punishments as merely the machinery in the hand of a
higher power, which is to serve only to set rational creatures
striving after their final end (happiness), this is to reduce the will
to a mechanism destructive of freedom; this is so evident that it need
not detain us.

More refined, though equally false, is the theory of those who
suppose a certain special moral sense, which sense and not reason
determines the moral law, and in consequence of which the
consciousness of virtue is supposed to be directly connected with
contentment and pleasure; that of vice, with mental dissatisfaction
and pain; thus reducing the whole to the desire of private
happiness. Without repeating what has been said above, I will here
only remark the fallacy they fall into. In order to imagine the
vicious man as tormented with mental dissatisfaction by the
consciousness of his transgressions, they must first represent him
as in the main basis of his character, at least in some degree,
morally good; just as he who is pleased with the consciousness of
right conduct must be conceived as already virtuous. The notion of
morality and duty must, therefore, have preceded any regard to this
satisfaction, and cannot be derived from it. A man must first
appreciate the importance of what we call duty, the authority of the
moral law, and the immediate dignity which the following of it gives
to the person in his own eyes, in order to feel that satisfaction in
the consciousness of his conformity to it and the bitter remorse
that accompanies the consciousness of its transgression. It is,
therefore, impossible to feel this satisfaction or dissatisfaction
prior to the knowledge of obligation, or to make it the basis of the
latter. A man must be at least half honest in order even to be able to
form a conception of these feelings. I do not deny that as the human
will is, by virtue of liberty, capable of being immediately determined
by the moral law, so frequent practice in accordance with this
principle of determination can, at least, produce subjectively a
feeling of satisfaction; on the contrary, it is a duty to establish
and to cultivate this, which alone deserves to be called properly
the moral feeling; but the notion of duty cannot be derived from it,
else we should have to suppose a feeling for the law as such, and thus
make that an object of sensation which can only be thought by the
reason; and this, if it is not to be a flat contradiction, would
destroy all notion of duty and put in its place a mere mechanical play
of refined inclinations sometimes contending with the coarser.

If now we compare our formal supreme principle of pure practical
reason (that of autonomy of the will) with all previous material
principles of morality, we can exhibit them all in a table in which
all possible cases are exhausted, except the one formal principle; and
thus we can show visibly that it is vain to look for any other
principle than that now proposed. In fact all possible principles of
determination of the will are either merely subjective, and
therefore empirical, or are also objective and rational; and both
are either external or internal.



Practical Material Principles of Determination taken as the
Foundation of Morality, are:

{BOOK_1|CHAPTER_1 ^paragraph 105}



SUBJECTIVE.



EXTERNAL INTERNAL

Education Physical feeling

{BOOK_1|CHAPTER_1 ^paragraph 110}

(Montaigne) (Epicurus)

The civil Moral feeling

Constitution (Hutcheson)

(Mandeville)



{BOOK_1|CHAPTER_1 ^paragraph 115}

OBJECTIVE.



INTERNAL EXTERNAL

Perfection Will of God

(Wolf and the (Crusius and other

{BOOK_1|CHAPTER_1 ^paragraph 120}

Stoics) theological Moralists)



Those of the upper table are all empirical and evidently incapable
of furnishing the universal principle of morality; but those in the
lower table are based on reason (for perfection as a quality of
things, and the highest perfection conceived as substance, that is,
God, can only be thought by means of rational concepts). But the
former notion, namely, that of perfection, may either be taken in a
theoretic signification, and then it means nothing but the
completeness of each thing in its own kind (transcendental), or that
of a thing merely as a thing (metaphysical); and with that we are
not concerned here. But the notion of perfection in a practical
sense is the fitness or sufficiency of a thing for all sorts of
purposes. This perfection, as a quality of man and consequently
internal, is nothing but talent and, what strengthens or completes
this, skill. Supreme perfection conceived as substance, that is God,
and consequently external (considered practically), is the sufficiency
of this being for all ends. Ends then must first be given,
relatively to which only can the notion of perfection (whether
internal in ourselves or external in God) be the determining principle
of the will. But an end- being an object which must precede the
determination of the will by a practical rule and contain the ground
of the possibility of this determination, and therefore contain also
the matter of the will, taken as its determining principle- such an
end is always empirical and, therefore, may serve for the Epicurean
principle of the happiness theory, but not for the pure rational
principle of morality and duty. Thus, talents and the improvement of
them, because they contribute to the advantages of life; or the will
of God, if agreement with it be taken as the object of the will,
without any antecedent independent practical principle, can be motives
only by reason of the happiness expected therefrom. Hence it
follows, first, that all the principles here stated are material;
secondly, that they include all possible material principles; and,
finally, the conclusion, that since material principles are quite
incapable of furnishing the supreme moral law (as has been shown), the
formal practical principle of the pure reason (according to which the
mere form of a universal legislation must constitute the supreme and
immediate determining principle of the will) is the only one
possible which is adequate to furnish categorical imperatives, that
is, practical laws (which make actions a duty), and in general to
serve as the principle of morality, both in criticizing conduct and
also in its application to the human will to determine it.



I. Of the Deduction of the Fundamental Principles of Pure
Practical Reason.

{BOOK_1|CHAPTER_1 ^paragraph 125}



This Analytic shows that pure reason can be practical, that is,
can of itself determine the will independently of anything
empirical; and this it proves by a fact in which pure reason in us
proves itself actually practical, namely, the autonomy shown in the
fundamental principle of morality, by which reason determines the will
to action.

It shows at the same time that this fact is inseparably connected
with the consciousness of freedom of the will, nay, is identical
with it; and by this the will of a rational being, although as
belonging to the world of sense it recognizes itself as necessarily
subject to the laws of causality like other efficient causes; yet,
at the same time, on another side, namely, as a being in itself, is
conscious of existing in and being determined by an intelligible order
of things; conscious not by virtue of a special intuition of itself,
but by virtue of certain dynamical laws which determine its
causality in the sensible world; for it has been elsewhere proved that
if freedom is predicated of us, it transports us into an
intelligible order of things.

Now, if we compare with this the analytical part of the critique
of pure speculative reason, we shall see a remarkable contrast.
There it was not fundamental principles, but pure, sensible
intuition (space and time), that was the first datum that made a
priori knowledge possible, though only of objects of the senses.
Synthetical principles could not be derived from mere concepts without
intuition; on the contrary, they could only exist with reference to
this intuition, and therefore to objects of possible experience, since
it is the concepts of the understanding, united with this intuition,
which alone make that knowledge possible which we call experience.
Beyond objects of experience, and therefore with regard to things as
noumena, all positive knowledge was rightly disclaimed for speculative
reason. This reason, however, went so far as to establish with
certainty the concept of noumena; that is, the possibility, nay, the
necessity, of thinking them; for example, it showed against all
objections that the supposition of freedom, negatively considered, was
quite consistent with those principles and limitations of pure
theoretic reason. But it could not give us any definite enlargement of
our knowledge with respect to such objects, but, on the contrary,
cut off all view of them altogether.

On the other hand, the moral law, although it gives no view, yet
gives us a fact absolutely inexplicable from any data of the
sensible world, and the whole compass of our theoretical use of
reason, a fact which points to a pure world of the understanding, nay,
even defines it positively and enables us to know something of it,
namely, a law.

{BOOK_1|CHAPTER_1 ^paragraph 130}

This law (as far as rational beings are concerned) gives to the
world of sense, which is a sensible system of nature, the form of a
world of the understanding, that is, of a supersensible system of
nature, without interfering with its mechanism. Now, a system of
nature, in the most general sense, is the existence of things under
laws. The sensible nature of rational beings in general is their
existence under laws empirically conditioned, which, from the point of
view of reason, is heteronomy. The supersensible nature of the same
beings, on the other hand, is their existence according to laws
which are independent of every empirical condition and, therefore,
belong to the autonomy of pure reason. And, since the laws by which
the existence of things depends on cognition are practical,
supersensible nature, so far as we can form any notion of it, is
nothing else than a system of nature under the autonomy of pure
practical reason. Now, the law of this autonomy is the moral law,
which, therefore, is the fundamental law of a supersensible nature,
and of a pure world of understanding, whose counterpart must exist
in the world of sense, but without interfering with its laws. We might
call the former the archetypal world (natura archetypa), which we only
know in the reason; and the latter the ectypal world (natura
ectypa), because it contains the possible effect of the idea of the
former which is the determining principle of the will. For the moral
law, in fact, transfers us ideally into a system in which pure reason,
if it were accompanied with adequate physical power, would produce the
summum bonum, and it determines our will to give the sensible world
the form of a system of rational beings.

The least attention to oneself proves that this idea really serves
as the model for the determinations of our will.

When the maxim which I am disposed to follow in giving testimony
is tested by the practical reason, I always consider what it would
be if it were to hold as a universal law of nature. It is manifest
that in this view it would oblige everyone to speak the truth. For
it cannot hold as a universal law of nature that statements should
be allowed to have the force of proof and yet to be purposely
untrue. Similarly, the maxim which I adopt with respect to disposing
freely of my life is at once determined, when I ask myself what it
should be, in order that a system, of which it is the law, should
maintain itself. It is obvious that in such a system no one could
arbitrarily put an end to his own life, for such an arrangement
would not be a permanent order of things. And so in all similar cases.
Now, in nature, as it actually is an object of experience, the free
will is not of itself determined to maxims which could of themselves
be the foundation of a natural system of universal laws, or which
could even be adapted to a system so constituted; on the contrary, its
maxims are private inclinations which constitute, indeed, a natural
whole in conformity with pathological (physical) laws, but could not
form part of a system of nature, which would only be possible
through our will acting in accordance with pure practical laws. Yet we
are, through reason, conscious of a law to which all our maxims are
subject, as though a natural order must be originated from our will.
This law, therefore, must be the idea of a natural system not given in
experience, and yet possible through freedom; a system, therefore,
which is supersensible, and to which we give objective reality, at
least in a practical point of view, since we look on it as an object
of our will as pure rational beings.

Hence the distinction between the laws of a natural system to
which the will is subject, and of a natural system which is subject to
a will (as far as its relation to its free actions is concerned),
rests on this, that in the former the objects must be causes of the
ideas which determine the will; whereas in the latter the will is
the cause of the objects; so that its causality has its determining
principle solely in the pure faculty of reason, which may therefore be
called a pure practical reason.

There are therefore two very distinct problems: how, on the one
side, pure reason can cognise objects a priori, and how on the other
side it can be an immediate determining principle of the will, that
is, of the causality of the rational being with respect to the reality
of objects (through the mere thought of the universal validity of
its own maxims as laws).

{BOOK_1|CHAPTER_1 ^paragraph 135}

The former, which belongs to the critique of the pure speculative
reason, requires a previous explanation, how intuitions without
which no object can be given, and, therefore, none known
synthetically, are possible a priori; and its solution turns out to be
that these are all only sensible and, therefore, do not render
possible any speculative knowledge which goes further than possible
experience reaches; and that therefore all the principles of that pure
speculative reason avail only to make experience possible; either
experience of given objects or of those that may be given ad
infinitum, but never are completely given.

The latter, which belongs to the critique of practical reason,
requires no explanation how the objects of the faculty of desire are
possible, for that being a problem of the theoretical knowledge of
nature is left to the critique of the speculative reason, but only how
reason can determine the maxims of the will; whether this takes
place only by means of empirical ideas as principles of determination,
or whether pure reason can be practical and be the law of a possible
order of nature, which is not empirically knowable. The possibility of
such a supersensible system of nature, the conception of which can
also be the ground of its reality through our own free will, does
not require any a priori intuition (of an intelligible world) which,
being in this case supersensible, would be impossible for us. For
the question is only as to the determining principle of volition in
its maxims, namely, whether it is empirical, or is a conception of the
pure reason (having the legal character belonging to it in general),
and how it can be the latter. It is left to the theoretic principles
of reason to decide whether the causality of the will suffices for the
realization of the objects or not, this being an inquiry into the
possibility of the objects of the volition. Intuition of these objects
is therefore of no importance to the practical problem. We are here
concerned only with the determination of the will and the
determining principles of its maxims as a free will, not at all with
the result. For, provided only that the will conforms to the law of
pure reason, then let its power in execution be what it may, whether
according to these maxims of legislation of a possible system of
nature any such system really results or not, this is no concern of
the critique, which only inquires whether, and in what way, pure
reason can be practical, that is directly determine the will.

In this inquiry criticism may and must begin with pure practical
laws and their reality. But instead of intuition it takes as their
foundation the conception of their existence in the intelligible
world, namely, the concept of freedom. For this concept has no other
meaning, and these laws are only possible in relation to freedom of
the will; but freedom being supposed, they are necessary; or
conversely freedom is necessary because those laws are necessary,
being practical postulates. It cannot be further explained how this
consciousness of the moral law, or, what is the same thing, of
freedom, is possible; but that it is admissible is well established in
the theoretical critique.

The exposition of the supreme principle of practical reason is now
finished; that is to say, it has been shown first, what it
contains, that it subsists for itself quite a priori and independent
of empirical principles; and next in what it is distinguished from all
other practical principles. With the deduction, that is, the
justification of its objective and universal validity, and the
discernment of the possibility of such a synthetical proposition a
priori, we cannot expect to succeed so well as in the case of the
principles of pure theoretical reason. For these referred to objects
of possible experience, namely, to phenomena, and we could prove
that these phenomena could be known as objects of experience only by
being brought under the categories in accordance with these laws;
and consequently that all possible experience must conform to these
laws. But I could not proceed in this way with the deduction of the
moral law. For this does not concern the knowledge of the properties
of objects, which may be given to the reason from some other source;
but a knowledge which can itself be the ground of the existence of the
objects, and by which reason in a rational being has causality,
i. e. , pure reason, which can be regarded as a faculty immediately
determining the will.

Now all our human insight is at an end as soon as we have arrived at
fundamental powers or faculties, for the possibility of these cannot
be understood by any means, and just as little should it be
arbitrarily invented and assumed. Therefore, in the theoretic use of
reason, it is experience alone that can justify us in assuming them.
But this expedient of adducing empirical proofs, instead of a
deduction from a priori sources of knowledge, is denied us here in
respect to the pure practical faculty of reason. For whatever requires
to draw the proof of its reality from experience must depend for the
grounds of its possibility on principles of experience; and pure,
yet practical, reason by its very notion cannot be regarded as such.
Further, the moral law is given as a fact of pure reason of which we
are a priori conscious, and which is apodeictically certain, though it
be granted that in experience no example of its exact fulfilment can
be found. Hence, the objective reality of the moral law cannot be
proved by any deduction by any efforts of theoretical reason,
whether speculative or empirically supported, and therefore, even if
we renounced its apodeictic certainty, it could not be proved a
posteriori by experience, and yet it is firmly established of itself.

{BOOK_1|CHAPTER_1 ^paragraph 140}

But instead of this vainly sought deduction of the moral
principle, something else is found which was quite unexpected, namely,
that this moral principle serves conversely as the principle of the
deduction of an inscrutable faculty which no experience could prove,
but of which speculative reason was compelled at least to assume the
possibility (in order to find amongst its cosmological ideas the
unconditioned in the chain of causality, so as not to contradict
itself)- I mean the faculty of freedom. The moral law, which itself
does not require a justification, proves not merely the possibility of
freedom, but that it really belongs to beings who recognize this law
as binding on themselves. The moral law is in fact a law of the
causality of free agents and, therefore, of the possibility of a
supersensible system of nature, just as the metaphysical law of events
in the world of sense was a law of causality of the sensible system of
nature; and it therefore determines what speculative philosophy was
compelled to leave undetermined, namely, the law for a causality,
the concept of which in the latter was only negative; and therefore
for the first time gives this concept objective reality.

This sort of credential of the moral law, viz. , that it is set forth
as a principle of the deduction of freedom, which is a causality of
pure reason, is a sufficient substitute for all a priori
justification, since theoretic reason was compelled to assume at least
the possibility of freedom, in order to satisfy a want of its own. For
the moral law proves its reality, so as even to satisfy the critique
of the speculative reason, by the fact that it adds a positive
definition to a causality previously conceived only negatively, the
possibility of which was incomprehensible to speculative reason, which
yet was compelled to suppose it. For it adds the notion of a reason
that directly determines the will (by imposing on its maxims the
condition of a universal legislative form); and thus it is able for
the first time to give objective, though only practical, reality to
reason, which always became transcendent when it sought to proceed
speculatively with its ideas. It thus changes the transcendent use
of reason into an immanent use (so that reason is itself, by means
of ideas, an efficient cause in the field of experience).

The determination of the causality of beings in the world of
sense, as such, can never be unconditioned; and yet for every series
of conditions there must be something unconditioned, and therefore
there must be a causality which is determined wholly by itself. Hence,
the idea of freedom as a faculty of absolute spontaneity was not found
to be a want but, as far as its possibility is concerned, an
analytic principle of pure speculative reason. But as it is absolutely
impossible to find in experience any example in accordance with this
idea, because amongst the causes of things as phenomena it would be
impossible to meet with any absolutely unconditioned determination
of causality, we were only able to defend our supposition that a
freely acting cause might be a being in the world of sense, in so
far as it is considered in the other point of view as a noumenon,
showing that there is no contradiction in regarding all its actions as
subject to physical conditions so far as they are phenomena, and yet
regarding its causality as physically unconditioned, in so far as
the acting being belongs to the world of understanding, and in thus
making the concept of freedom the regulative principle of reason. By
this principle I do not indeed learn what the object is to which
that sort of causality is attributed; but I remove the difficulty,
for, on the one side, in the explanation of events in the world, and
consequently also of the actions of rational beings, I leave to the
mechanism of physical necessity the right of ascending from
conditioned to condition ad infinitum, while on the other side I
keep open for speculative reason the place which for it is vacant,
namely, the intelligible, in order to transfer the unconditioned
thither. But I was not able to verify this supposition; that is, to
change it into the knowledge of a being so acting, not even into the
knowledge of the possibility of such a being. This vacant place is now
filled by pure practical reason with a definite law of causality in an
intelligible world (causality with freedom), namely, the moral law.
Speculative reason does not hereby gain anything as regards its
insight, but only as regards the certainty of its problematical notion
of freedom, which here obtains objective reality, which, though only
practical, is nevertheless undoubted. Even the notion of causality-
the application, and consequently the signification, of which holds
properly only in relation to phenomena, so as to connect them into
experiences (as is shown by the Critique of Pure Reason)- is not so
enlarged as to extend its use beyond these limits. For if reason
sought to do this, it would have to show how the logical relation of
principle and consequence can be used synthetically in a different
sort of intuition from the sensible; that is how a causa noumenon is
possible. This it can never do; and, as practical reason, it does
not even concern itself with it, since it only places the
determining principle of causality of man as a sensible creature
(which is given) in pure reason (which is therefore called practical);
and therefore it employs the notion of cause, not in order to know
objects, but to determine causality in relation to objects in general.
It can abstract altogether from the application of this notion to
objects with a view to theoretical knowledge (since this concept is
always found a priori in the understanding even independently of any
intuition). Reason, then, employs it only for a practical purpose, and
hence we can transfer the determining principle of the will into the
intelligible order of things, admitting, at the same time, that we
cannot understand how the notion of cause can determine the
knowledge of these things. But reason must cognise causality with
respect to the actions of the will in the sensible world in a definite
manner; otherwise, practical reason could not really produce any
action. But as to the notion which it forms of its own causality as
noumenon, it need not determine it theoretically with a view to the
cognition of its supersensible existence, so as to give it
significance in this way. For it acquires significance apart from
this, though only for practical use, namely, through the moral law.
Theoretically viewed, it remains always a pure a priori concept of the
understanding, which can be applied to objects whether they have
been given sensibly or not, although in the latter case it has no
definite theoretical significance or application, but is only a
formal, though essential, conception of the understanding relating
to an object in general. The significance which reason gives it
through the moral law is merely practical, inasmuch as the idea of
the law of causality (of the will) has self causality, or is
its determining principle.



II. Of the Right that Pure Reason in its Practical use has to an
Extension which is not possible to it in its Speculative Use.

{BOOK_1|CHAPTER_1 ^paragraph 145}



We have in the moral principle set forth a law of causality, the
determining principle of which is set above all the conditions of
the sensible world; we have it conceived how the will, as belonging
to the intelligible world, is determinable, and therefore have
its subject (man) not merely conceived as belonging to a world of
pure understanding, and in this respect unknown (which the critique of
speculative reason enabled us to do), but also defined as regards
his causality by means of a law which cannot be reduced to any
physical law of the sensible world; and therefore our knowledge is
extended beyond the limits of that world, a pretension which the
Critique of Pure Reason declared to be futile in all speculation. Now,
how is the practical use of pure reason here to be reconciled with the
theoretical, as to the determination of the limits of its faculty?

David Hume, of whom we may say that he commenced the assault on
the claims of pure reason, which made a thorough investigation of it
necessary, argued thus: The notion of cause is a notion that
involves the necessity of the connexion of the existence of
different things (and that, in so far as they are different), so that,
given A, I know that something quite distinct there from, namely B,
must necessarily also exist. Now necessity can be attributed to a
connection, only in so far as it is known a priori, for experience
would only enable us to know of such a connection that it exists,
not that it necessarily exists. Now, it is impossible, says he, to
know a priori and as necessary the connection between one thing and
another (or between one attribute and another quite distinct) when
they have not been given in experience. Therefore the notion of a
cause is fictitious and delusive and, to speak in the mildest way,
is an illusion, only excusable inasmuch as the custom (a subjective
necessity) of perceiving certain things, or their attributes as
often associated in existence along with or in succession to one
another, is insensibly taken for an objective necessity of supposing
such a connection in the objects themselves; and thus the notion of
a cause has been acquired surreptitiously and not legitimately; nay,
it can never be so acquired or authenticated, since it demands a
connection in itself vain, chimerical, and untenable in presence of
reason, and to which no object can ever correspond. In this way was
empiricism first introduced as the sole source of principles, as far
as all knowledge of the existence of things is concerned
(mathematics therefore remaining excepted); and with empiricism the
most thorough scepticism, even with regard to the whole science of
nature( as philosophy). For on such principles we can never conclude
from given attributes of things as existing to a consequence (for this
would require the notion of cause, which involves the necessity of
such a connection); we can only, guided by imagination, expect similar
cases- an expectation which is never certain, however often it has
been fulfilled. Of no event could we say: a certain thing must have
preceded it, on which it necessarily followed; that is, it must have a
cause; and therefore, however frequent the cases we have known in
which there was such an antecedent, so that a rule could be derived
from them, yet we never could suppose it as always and necessarily
so happening; we should, therefore, be obliged to leave its share to
blind chance, with which all use of reason comes to an end; and this
firmly establishes scepticism in reference to arguments ascending from
effects to causes and makes it impregnable.

Mathematics escaped well, so far, because Hume thought that its
propositions were analytical; that is, proceeded from one property
to another, by virtue of identity and, consequently, according to
the principle of contradiction. This, however, is not the case, since,
on the contrary, they are synthetical; and although geometry, for
example, has not to do with the existence of things, but only with
their a priori properties in a possible intuition, yet it proceeds
just as in the case of the causal notion, from one property (A) to
another wholly distinct (B), as necessarily connected with the former.
Nevertheless, mathematical science, so highly vaunted for its
apodeictic certainty, must at last fall under this empiricism for
the same reason for which Hume put custom in the place of objective
necessity in the notion of cause and, in spite of all its pride,
must consent to lower its bold pretension of claiming assent a
priori and depend for assent to the universality of its propositions
on the kindness of observers, who, when called as witnesses, would
surely not hesitate to admit that what the geometer propounds as a
theorem they have always perceived to be the fact, and,
consequently, although it be not necessarily true, yet they would
permit us to expect it to be true in the future. In this manner Hume's
empiricism leads inevitably to scepticism, even with regard to
mathematics, and consequently in every scientific theoretical use of
reason (for this belongs either to philosophy or mathematics). Whether
with such a terrible overthrow of the chief branches of knowledge,
common reason will escape better, and will not rather become
irrecoverably involved in this destruction of all knowledge, so that
from the same principles a universal scepticism should follow
(affecting, indeed, only the learned), this I will leave everyone to
judge for himself.

As regards my own labours in the critical examination of pure
reason, which were occasioned by Hume's sceptical teaching, but went
much further and embraced the whole field of pure theoretical reason
in its synthetic use and, consequently, the field of what is called
metaphysics in general; I proceeded in the following manner with
respect to the doubts raised by the Scottish philosopher touching
the notion of causality. If Hume took the objects of experience for
things in themselves (as is almost always done), he was quite right in
declaring the notion of cause to be a deception and false illusion;
for as to things in themselves, and their attributes as such, it is
impossible to see why because A is given, B, which is different,
must necessarily be also given, and therefore he could by no means
admit such an a priori knowledge of things in themselves. Still less
could this acute writer allow an empirical origin of this concept,
since this is directly contradictory to the necessity of connection
which constitutes the essence of the notion of causality, hence the
notion was proscribed, and in its place was put custom in the
observation of the course of perceptions.

{BOOK_1|CHAPTER_1 ^paragraph 150}

It resulted, however, from my inquiries, that the objects with which
we have to do in experience are by no means things in themselves,
but merely phenomena; and that although in the case of things in
themselves it is impossible to see how, if A is supposed, it should be
contradictory that B, which is quite different from A, should not also
be supposed (i. e. , to see the necessity of the connection between A as
cause and B as effect); yet it can very well be conceived that, as
phenomena, they may be necessarily connected in one experience in a
certain way (e. g. , with regard to time-relations); so that they
could not be separated without contradicting that connection, by means
of which this experience is possible in which they are objects and
in which alone they are cognisable by us. And so it was found to be in
fact; so that I was able not only to prove the objective reality of
the concept of cause in regard to objects of experience, but also to
deduce it as an a priori concept by reason of the necessity of the
connection it implied; that is, to show the possibility of its
origin from pure understanding without any empirical sources; and
thus, after removing the source of empiricism, I was able also to
overthrow the inevitable consequence of this, namely, scepticism,
first with regard to physical science, and then with regard to
mathematics (in which empiricism has just the same grounds), both
being sciences which have reference to objects of possible experience;
herewith overthrowing the thorough doubt of whatever theoretic
reason professes to discern.

But how is it with the application of this category of causality
(and all the others; for without them there can be no knowledge of
anything existing) to things which are not objects of possible
experience, but lie beyond its bounds? For I was able to deduce the
objective reality of these concepts only with regard to objects of
possible experience. But even this very fact, that I have saved
them, only in case I have proved that objects may by means of them
be thought, though not determined a priori; this it is that gives them
a place in the pure understanding, by which they are referred to
objects in general (sensible or not sensible). If anything is still
wanting, it is that which is the condition of the application of these
categories, and especially that of causality, to objects, namely,
intuition; for where this is not given, the application with a view to
theoretic knowledge of the object, as a noumenon, is impossible and,
therefore, if anyone ventures on it, is (as in the Critique of Pure
Reason) absolutely forbidden. Still, the objective reality of the
concept (of causality) remains, and it can be used even of noumena,
but without our being able in the least to define the concept
theoretically so as to produce knowledge. For that this concept,
even in reference to an object, contains nothing impossible, was shown
by this, that, even while applied to objects of sense, its seat was
certainly fixed in the pure understanding; and although, when referred
to things in themselves (which cannot be objects of experience), it is
not capable of being determined so as to represent a definite object
for the purpose of theoretic knowledge; yet for any other purpose (for
instance, a practical) it might be capable of being determined so as
to have such application. This could not be the case if, as Hume
maintained, this concept of causality contained something absolutely
impossible to be thought.

In order now to discover this condition of the application of the
said concept to noumena, we need only recall why we are not content
with its application to objects of experience, but desire also to
apply it to things in themselves. It will appear, then, that it is not
a theoretic but a practical purpose that makes this a necessity. In
speculation, even if we were successful in it, we should not really
gain anything in the knowledge of nature, or generally with regard
to such objects as are given, but we should make a wide step from
the sensibly conditioned (in which we have already enough to do to
maintain ourselves, and to follow carefully the chain of causes) to
the supersensible, in order to complete our knowledge of principles
and to fix its limits; whereas there always remains an infinite
chasm unfilled between those limits and what we know; and we should
have hearkened to a vain curiosity rather than a solid-desire of
knowledge.

But, besides the relation in which the understanding stands to
objects (in theoretical knowledge), it has also a relation to the
faculty of desire, which is therefore called the will, and the pure
will, inasmuch as pure understanding (in this case called reason) is
practical through the mere conception of a law. The objective
reality of a pure will, or, what is the same thing, of a pure
practical reason, is given in the moral law a priori, as it were, by a
fact, for so we may name a determination of the will which is
inevitable, although it does not rest on empirical principles. Now, in
the notion of a will the notion of causality is already contained, and
hence the notion of a pure will contains that of a causality
accompanied with freedom, that is, one which is not determinable by
physical laws, and consequently is not capable of any empirical
intuition in proof of its reality, but, nevertheless, completely
justifies its objective reality a priori in the pure practical law;
not, indeed (as is easily seen) for the purposes of the theoretical,
but of the practical use of reason. Now the notion of a being that has
free will is the notion of a causa noumenon, and that this notion
involves no contradiction, we are already assured by the fact- that
inasmuch as the concept of cause has arisen wholly from pure
understanding, and has its objective reality assured by the deduction,
as it is moreover in its origin independent of any sensible
conditions, it is, therefore, not restricted to phenomena (unless we
wanted to make a definite theoretic use of it), but can be applied
equally to things that are objects of the pure understanding. But,
since this application cannot rest on any intuition (for intuition can
only be sensible), therefore, causa noumenon, as regards the theoretic
use of reason, although a possible and thinkable, is yet an empty
notion. Now, I do not desire by means of this to understand
theoretically the nature of a being, in so far as it has a pure
will; it is enough for me to have thereby designated it as such, and
hence to combine the notion of causality with that of freedom (and
what is inseparable from it, the moral law, as its determining
principle). Now, this right I certainly have by virtue of the pure,
not-empirical origin of the notion of cause, since I do not consider
myself entitled to make any use of it except in reference to the moral
law which determines its reality, that is, only a practical use.

If, with Hume, I had denied to the notion of causality all objective
reality in its [theoretic] use, not merely with regard to things in
themselves (the supersensible), but also with regard to the objects of
the senses, it would have lost all significance, and being a
theoretically impossible notion would have been declared to be quite
useless; and since what is nothing cannot be made any use of, the
practical use of a concept theoretically null would have been
absurd. But, as it is, the concept of a causality free from
empirical conditions, although empty, i. e. , without any appropriate
intuition), is yet theoretically possible, and refers to an
indeterminate object; but in compensation significance is given to
it in the moral law and consequently in a practical sense. I have,
indeed, no intuition which should determine its objective theoretic
reality, but not the less it has a real application, which is
exhibited in concreto in intentions or maxims; that is, it has a
practical reality which can be specified, and this is sufficient to
justify it even with a view to noumena.

{BOOK_1|CHAPTER_1 ^paragraph 155}

Now, this objective reality of a pure concept of the understanding
in the sphere of the supersensible, once brought in, gives an
objective reality also to all the other categories, although only so
far as they stand in necessary connexion with the determining
principle of the will (the moral law); a reality only of practical
application, which has not the least effect in enlarging our
theoretical knowledge of these objects, or the discernment of their
nature by pure reason. So we shall find also in the sequel that
these categories refer only to beings as intelligences, and in them
only to the relation of reason to the will; consequently, always
only to the practical, and beyond this cannot pretend to any knowledge
of these beings; and whatever other properties belonging to the
theoretical representation of supersensible things may be brought into
connexion with these categories, this is not to be reckoned as
knowledge, but only as a right (in a practical point of view, however,
it is a necessity) to admit and assume such beings, even in the case
where we [conceive] supersensible beings (e. g. , God) according to
analogy, that is, a purely rational relation, of which we make a
practical use with reference to what is sensible; and thus the
application to the supersensible solely in a practical point of view
does not give pure theoretic reason the least encouragement to run
riot into the transcendent.

BOOK_1|CHAPTER_2

CHAPTER II. Of the Concept of an Object of Pure Practical Reason.



By a concept of the practical reason I understand the idea of an
object as an effect possible to be produced through freedom. To be
an object of practical knowledge, as such, signifies, therefore,
only the relation of the will to the action by which the object or its
opposite would be realized; and to decide whether something is an
object of pure practical reason or not is only to discern the
possibility or impossibility of willing the action by which, if we had
the required power (about which experience must decide), a certain
object would be realized. If the object be taken as the determining
principle of our desire, it must first be known whether it is
physically possible by the free use of our powers, before we decide
whether it is an object of practical reason or not. On the other hand,
if the law can be considered a priori as the determining principle
of the action, and the latter therefore as determined by pure
practical reason, the judgement whether a thing is an object of pure
practical reason or not does not depend at all on the comparison
with our physical power; and the question is only whether we should
will an action that is directed to the existence of an object, if
the object were in our power; hence the previous question is only as
the moral possibility of the action, for in this case it is not the
object, but the law of the will, that is the determining principle
of the action. The only objects of practical reason are therefore
those of good and evil. For by the former is meant an object
necessarily desired according to a principle of reason; by the
latter one necessarily shunned, also according to a principle of
reason.

If the notion of good is not to be derived from an antecedent
practical law, but, on the contrary, is to serve as its foundation, it
can only be the notion of something whose existence promises pleasure,
and thus determines the causality of the subject to produce it, that
is to say, determines the faculty of desire. Now, since it is
impossible to discern a priori what idea will be accompanied with
pleasure and what with pain, it will depend on experience alone to
find out what is primarily good or evil. The property of the
subject, with reference to which alone this experiment can be made, is
the feeling of pleasure and pain, a receptivity belonging to the
internal sense; thus that only would be primarily good with which
the sensation of pleasure is immediately connected, and that simply
evil which immediately excites pain. Since, however, this is opposed
even to the usage of language, which distinguishes the pleasant from
the good, the unpleasant from the evil, and requires that good and
evil shall always be judged by reason, and, therefore, by concepts
which can be communicated to everyone, and not by mere sensation,
which is limited to individual [subjects] and their susceptibility;
and, since nevertheless, pleasure or pain cannot be connected with any
idea of an object a priori, the philosopher who thought himself
obliged to make a feeling of pleasure the foundation of his
practical judgements would call that good which is a means to the
pleasant, and evil, what is a cause of unpleasantness and pain; for
the judgement on the relation of means to ends certainly belongs to
reason. But, although reason is alone capable of discerning the
connexion of means with their ends (so that the will might even be
defined as the faculty of ends, since these are always determining
principles of the desires), yet the practical maxims which would
follow from the aforesaid principle of the good being merely a
means, would never contain as the object of the will anything good
in itself, but only something good for something; the good would
always be merely the useful, and that for which it is useful must
always lie outside the will, in sensation. Now if this as a pleasant
sensation were to be distinguished from the notion of good, then there
would be nothing primarily good at all, but the good would have to
be sought only in the means to something else, namely, some
pleasantness.

It is an old formula of the schools: Nihil appetimus nisi sub
ratione boni; Nihil aversamur nisi sub ratione mali, and it is used
often correctly, but often also in a manner injurious to philosophy,
because the expressions boni and mali are ambiguous, owing to the
poverty of language, in consequence of which they admit a double
sense, and, therefore, inevitably bring the practical laws into
ambiguity; and philosophy, which in employing them becomes aware of
the different meanings in the same word, but can find no special
expressions for them, is driven to subtile distinctions about which
there is subsequently no unanimity, because the distinction could
not be directly marked by any suitable expression. *



* Besides this, the expression sub ratione boni is also ambiguous.
For it may mean: "We represent something to ourselves as good, when
and because we desire (will) it"; or "We desire something because we
represent it to ourselves as good," so that either the desire
determines the notion of the object as a good, or the notion of good
determines the desire (the will); so that in the first case sub
ratione boni would mean, "We will something under the idea of the
good"; in the second, "In consequence of this idea," which, as
determining the volition, must precede it.

{BOOK_1|CHAPTER_2 ^paragraph 5}



The German language has the good fortune to possess expressions
which do not allow this difference to be overlooked. It possesses
two very distinct concepts and especially distinct expressions for
that which the Latins express by a single word, bonum. For bonum it
has das Gute [good], and das Wohl [well, weal], for malum das Bose
[evil], and das Ubel [ill, bad], or das Well [woe]. So that we express
two quite distinct judgements when we consider in an action the good
and evil of it, or our weal and woe (ill). Hence it already follows
that the above quoted psychological proposition is at least very
doubtful if it is translated: "We desire nothing except with a view to
our weal or woe"; on the other hand, if we render it thus: "Under
the direction of reason we desire nothing except so far as we esteem
it good or evil," it is indubitably certain and at the same time quite
clearly expressed.

Well or ill always implies only a reference to our condition, as
pleasant or unpleasant, as one of pleasure or pain, and if we desire
or avoid an object on this account, it is only so far as it is
referred to our sensibility and to the feeling of pleasure or pain
that it produces. But good or evil always implies a reference to the
will, as determined by the law of reason, to make something its
object; for it is never determined directly by the object and the idea
of it, but is a faculty of taking a rule of reason for or motive of an
action (by which an object may be realized). Good and evil therefore
are properly referred to actions, not to the sensations of the person,
and if anything is to be good or evil absolutely (i. e. , in every
respect and without any further condition), or is to be so esteemed,
it can only be the manner of acting, the maxim of the will, and
consequently the acting person himself as a good or evil man that
can be so called, and not a thing.

However, then, men may laugh at the Stoic, who in the severest
paroxysms of gout cried out: "Pain, however thou tormentest me, I will
never admit that thou art an evil (kakov, malum)": he was right. A bad
thing it certainly was, and his cry betrayed that; but that any evil
attached to him thereby, this he had no reason whatever to admit,
for pain did not in the least diminish the worth of his person, but
only that of his condition. If he had been conscious of a single
lie, it would have lowered his pride, but pain served only to raise
it, when he was conscious that he had not deserved it by any
unrighteous action by which he had rendered himself worthy of
punishment.

What we call good must be an object of desire in the judgement of
every rational man, and evil an object of aversion in the eyes of
everyone; therefore, in addition to sense, this judgement requires
reason. So it is with truthfulness, as opposed to lying; so with
justice, as opposed to violence, &c. But we may call a thing a bad [or
ill] thing, which yet everyone must at the same time acknowledge to be
good, sometimes directly, sometimes indirectly. The man who submits to
a surgical operation feels it no doubt as a bad thing, but by their
reason he and everyone acknowledge it to be good. If a man who
delights in annoying and vexing peaceable people at last receives a
right good beating, this is no doubt a bad thing; but everyone
approves it and regards it as a good thing, even though nothing else
resulted from it; nay, even the man who receives it must in his reason
acknowledge that he has met justice, because he sees the proportion
between good conduct and good fortune, which reason inevitably
places before him, here put into practice.

{BOOK_1|CHAPTER_2 ^paragraph 10}

No doubt our weal and woe are of very great importance in the
estimation of our practical reason, and as far as our nature as
sensible beings is concerned, our happiness is the only thing of
consequence, provided it is estimated as reason especially requires,
not by the transitory sensation, but by the influence that this has on
our whole existence, and on our satisfaction therewith; but it is
not absolutely the only thing of consequence. Man is a being who, as
belonging to the world of sense, has wants, and so far his reason
has an office which it cannot refuse, namely, to attend to the
interest of his sensible nature, and to form practical maxims, even
with a view to the happiness of this life, and if possible even to
that of a future. But he is not so completely an animal as to be
indifferent to what reason says on its own account, and to use it
merely as an instrument for the satisfaction of his wants as a
sensible being. For the possession of reason would not raise his worth
above that of the brutes, if it is to serve him only for the same
purpose that instinct serves in them; it would in that case be only
a particular method which nature had employed to equip man for the
same ends for which it has qualified brutes, without qualifying him
for any higher purpose. No doubt once this arrangement of nature has
been made for him he requires reason in order to take into
consideration his weal and woe, but besides this he possesses it for a
higher purpose also, namely, not only to take into consideration
what is good or evil in itself, about which only pure reason,
uninfluenced by any sensible interest, can judge, but also to
distinguish this estimate thoroughly from the former and to make it
the supreme condition thereof.

In estimating what is good or evil in itself, as distinguished
from what can be so called only relatively, the following points are
to be considered. Either a rational principle is already conceived, as
of itself the determining principle of the will, without regard to
possible objects of desire (and therefore by the more legislative form
of the maxim), and in that case that principle is a practical a priori
law, and pure reason is supposed to be practical of itself. The law in
that case determines the will directly; the action conformed to it
is good in itself; a will whose maxim always conforms to this law is
good absolutely in every respect and is the supreme condition of all
good. Or the maxim of the will is consequent on a determining
principle of desire which presupposes an object of pleasure or pain,
something therefore that pleases or displeases, and the maxim of
reason that we should pursue the former and avoid the latter
determines our actions as good relatively to our inclination, that is,
good indirectly, (i. e. , relatively to a different end to which they are
means), and in that case these maxims can never be called laws, but
may be called rational practical precepts. The end itself, the
pleasure that we seek, is in the latter case not a good but a welfare;
not a concept of reason, but an empirical concept of an object of
sensation; but the use of the means thereto, that is, the action, is
nevertheless called good (because rational deliberation is required
for it), not however, good absolutely, but only relatively to our
sensuous nature, with regard to its feelings of pleasure and
displeasure; but the will whose maxim is affected thereby is not a
pure will; this is directed only to that in which pure reason by
itself can be practical.

This is the proper place to explain the paradox of method in a
critique of practical reason, namely, that the concept of good and
evil must not be determined before the moral law (of which it seems as
if it must be the foundation), but only after it and by means of it.
In fact, even if we did not know that the principle of morality is a
pure a priori law determining the will, yet, that we may not assume
principles quite gratuitously, we must, at least at first, leave it
undecided, whether the will has merely empirical principles of
determination, or whether it has not also pure a priori principles;
for it is contrary to all rules of philosophical method to assume as
decided that which is the very point in question. Supposing that we
wished to begin with the concept of good, in order to deduce from it
the laws of the will, then this concept of an object (as a good) would
at the same time assign to us this object as the sole determining
principle of the will. Now, since this concept had not any practical a
priori law for its standard, the criterion of good or evil could not
be placed in anything but the agreement of the object with our feeling
of pleasure or pain; and the use of reason could only consist in
determining in the first place this pleasure or pain in connexion with
all the sensations of my existence, and in the second place the
means of securing to myself the object of the pleasure. Now, as
experience alone can decide what conforms to the feeling of
pleasure, and by hypothesis the practical law is to be based on this
as a condition, it follows that the possibility of a priori
practical laws would be at once excluded, because it was imagined to
be necessary first of all to find an object the concept of which, as a
good, should constitute the universal though empirical principle of
determination of the will. But what it was necessary to inquire
first of all was whether there is not an a priori determining
principle of the will (and this could never be found anywhere but in a
pure practical law, in so far as this law prescribes to maxims
merely their form without regard to an object). Since, however, we
laid the foundation of all practical law in an object determined by
our conceptions of good and evil, whereas without a previous law
that object could not be conceived by empirical concepts, we have
deprived ourselves beforehand of the possibility of even conceiving
a pure practical law. On the other hand, if we had first
investigated the latter analytically, we should have found that it
is not the concept of good as an object that determines the moral
law and makes it possible, but that, on the contrary, it is the
moral law that first determines the concept of good and makes it
possible, so far as it deserves the name of good absolutely.

This remark, which only concerns the method of ultimate ethical
inquiries, is of importance. It explains at once the occasion of all
the mistakes of philosophers with respect to the supreme principle
of morals. For they sought for an object of the will which they
could make the matter and principle of a law (which consequently could
not determine the will directly, but by means of that object
referred to the feeling of pleasure or pain; whereas they ought
first to have searched for a law that would determine the will a
priori and directly, and afterwards determine the object in accordance
with the will). Now, whether they placed this object of pleasure,
which was to supply the supreme conception of goodness, in
happiness, in perfection, in moral [feeling], or in the will of God,
their principle in every case implied heteronomy, and they must
inevitably come upon empirical conditions of a moral law, since
their object, which was to be the immediate principle of the will,
could not be called good or bad except in its immediate relation to
feeling, which is always empirical. It is only a formal law- that
is, one which prescribes to reason nothing more than the form of its
universal legislation as the supreme condition of its maxims- that can
be a priori a determining principle of practical reason. The
ancients avowed this error without concealment by directing all
their moral inquiries to the determination of the notion of the summum
bonum, which they intended afterwards to make the determining
principle of the will in the moral law; whereas it is only far
later, when the moral law has been first established for itself, and
shown to be the direct determining principle of the will, that this
object can be presented to the will, whose form is now determined a
priori; and this we shall undertake in the Dialectic of the pure
practical reason. The moderns, with whom the question of the summum
bonum has gone out of fashion, or at least seems to have become a
secondary matter, hide the same error under vague (expressions as in
many other cases). It shows itself, nevertheless, in their systems, as
it always produces heteronomy of practical reason; and from this can
never be derived a moral law giving universal commands.

Now, since the notions of good and evil, as consequences of the a
priori determination of the will, imply also a pure practical
principle, and therefore a causality of pure reason; hence they do not
originally refer to objects (so as to be, for instance, special
modes of the synthetic unity of the manifold of given intuitions in
one consciousness) like the pure concepts of the understanding or
categories of reason in its theoretic employment; on the contrary,
they presuppose that objects are given; but they are all modes
(modi) of a single category, namely, that of causality, the
determining principle of which consists in the rational conception
of a law, which as a law of freedom reason gives to itself, thereby
a priori proving itself practical. However, as the actions on the
one side come under a law which is not a physical law, but a law of
freedom, and consequently belong to the conduct of beings in the world
of intelligence, yet on the other side as events in the world of sense
they belong to phenomena; hence the determinations of a practical
reason are only possible in reference to the latter and, therefore, in
accordance with the categories of the understanding; not indeed with a
view to any theoretic employment of it, i. e. , so as to bring the
manifold of (sensible) intuition under one consciousness a priori; but
only to subject the manifold of desires to the unity of
consciousness of a practical reason, giving it commands in the moral
law, i. e. , to a pure will a priori.

{BOOK_1|CHAPTER_2 ^paragraph 15}

These categories of freedom- for so we choose to call them in
contrast to those theoretic categories which are categories of
physical nature- have an obvious advantage over the latter, inasmuch
as the latter are only forms of thought which designate objects in
an indefinite manner by means of universal concept of every possible
intuition; the former, on the contrary, refer to the determination
of a free elective will (to which indeed no exactly corresponding
intuition can be assigned, but which has as its foundation a pure
practical a priori law, which is not the case with any concepts
belonging to the theoretic use of our cognitive faculties); hence,
instead of the form of intuition (space and time), which does not
lie in reason itself, but has to be drawn from another source, namely,
the sensibility, these being elementary practical concepts have as
their foundation the form of a pure will, which is given in reason
and, therefore, in the thinking faculty itself. From this it happens
that as all precepts of pure practical reason have to do only with the
determination of the will, not with the physical conditions (of
practical ability) of the execution of one's purpose, the practical
a priori principles in relation to the supreme principle of freedom
are at once cognitions, and have not to wait for intuitions in order
to acquire significance, and that for this remarkable reason,
because they themselves produce the reality of that to which they
refer (the intention of the will), which is not the case with
theoretical concepts. Only we must be careful to observe that these
categories only apply to the practical reason; and thus they proceed
in order from those which are as yet subject to sensible conditions
and morally indeterminate to those which are free from sensible
conditions and determined merely by the moral law.



Table of the Categories of Freedom relatively to the Notions of Good
and Evil.



I. QUANTITY.

{BOOK_1|CHAPTER_2 ^paragraph 20}

Subjective, according to maxims (practical opinions of the

individual)

Objective, according to principles (Precepts)

A priori both objective and subjective principles of freedom

(laws)

{BOOK_1|CHAPTER_2 ^paragraph 25}



II. QUALITY.

Practical rules of action (praeceptivae)

Practical rules of omission (prohibitivae)

Practical rules of exceptions (exceptivae)

{BOOK_1|CHAPTER_2 ^paragraph 30}



III. RELATION.

To personality

To the condition of the person.

Reciprocal, of one person to the others of the others.



{BOOK_1|CHAPTER_2 ^paragraph 35}

IV. MODALITY.

The Permitted and the Forbidden

Duty and the contrary to duty.

Perfect and imperfect duty.



{BOOK_1|CHAPTER_2 ^paragraph 40}

It will at once be observed that in this table freedom is considered
as a sort of causality not subject to empirical principles of
determination, in regard to actions possible by it, which are
phenomena in the world of sense, and that consequently it is
referred to the categories which concern its physical possibility,
whilst yet each category is taken so universally that the
determining principle of that causality can be placed outside the
world of sense in freedom as a property of a being in the world of
intelligence; and finally the categories of modality introduce the
transition from practical principles generally to those of morality,
but only problematically. These can be established dogmatically only
by the moral law.

I add nothing further here in explanation of the present table,
since it is intelligible enough of itself. A division of this kind
based on principles is very useful in any science, both for the sake
of thoroughness and intelligibility. Thus, for instance, we know
from the preceding table and its first number what we must begin
from in practical inquiries; namely, from the maxims which every one
founds on his own inclinations; the precepts which hold for a
species of rational beings so far as they agree in certain
inclinations; and finally the law which holds for all without regard
to their inclinations, etc. In this way we survey the whole plan of
what has to be done, every question of practical philosophy that has
to be answered, and also the order that is to be followed.



Of the Typic of the Pure Practical Judgement.



{BOOK_1|CHAPTER_2 ^paragraph 45}

It is the notions of good and evil that first determine an object of
the will. They themselves, however, are subject to a practical rule of
reason which, if it is pure reason, determines the will a priori
relatively to its object. Now, whether an action which is possible
to us in the world of sense, comes under the rule or not, is a
question to be decided by the practical judgement, by which what is
said in the rule universally (in abstracto) is applied to an action in
concreto. But since a practical rule of pure reason in the first place
as practical concerns the existence of an object, and in the second
place as a practical rule of pure reason implies necessity as
regards the existence of the action and, therefore, is a practical
law, not a physical law depending on empirical principles of
determination, but a law of freedom by which the will is to be
determined independently on anything empirical (merely by the
conception of a law and its form), whereas all instances that can
occur of possible actions can only be empirical, that is, belong to
the experience of physical nature; hence, it seems absurd to expect to
find in the world of sense a case which, while as such it depends only
on the law of nature, yet admits of the application to it of a law
of freedom, and to which we can apply the supersensible idea of the
morally good which is to be exhibited in it in concreto. Thus, the
judgement of the pure practical reason is subject to the same
difficulties as that of the pure theoretical reason. The latter,
however, had means at hand of escaping from these difficulties,
because, in regard to the theoretical employment, intuitions were
required to which pure concepts of the understanding could be applied,
and such intuitions (though only of objects of the senses) can be
given a priori and, therefore, as far as regards the union of the
manifold in them, conforming to the pure a priori concepts of the
understanding as schemata. On the other hand, the morally good is
something whose object is supersensible; for which, therefore, nothing
corresponding can be found in any sensible intuition. Judgement
depending on laws of pure practical reason seems, therefore, to be
subject to special difficulties arising from this, that a law of
freedom is to be applied to actions, which are events taking place
in the world of sense, and which, so far, belong to physical nature.

But here again is opened a favourable prospect for the pure
practical judgement. When I subsume under a pure practical law an
action possible to me in the world of sense, I am not concerned with
the possibility of the action as an event in the world of sense.
This is a matter that belongs to the decision of reason in its
theoretic use according to the law of causality, which is a pure
concept of the understanding, for which reason has a schema in the
sensible intuition. Physical causality, or the condition under which
it takes place, belongs to the physical concepts, the schema of
which is sketched by transcendental imagination. Here, however, we
have to do, not with the schema of a case that occurs according to
laws, but with the schema of a law itself (if the word is allowable
here), since the fact that the will (not the action relatively to
its effect) is determined by the law alone without any other
principle, connects the notion of causality with quite different
conditions from those which constitute physical connection.

The physical law being a law to which the objects of sensible
intuition, as such, are subject, must have a schema corresponding to
it- that is, a general procedure of the imagination (by which it
exhibits a priori to the senses the pure concept of the
understanding which the law determines). But the law of freedom
(that is, of a causality not subject to sensible conditions), and
consequently the concept of the unconditionally good, cannot have
any intuition, nor consequently any schema supplied to it for the
purpose of its application in concreto. Consequently the moral law has
no faculty but the understanding to aid its application to physical
objects (not the imagination); and the understanding for the
purposes of the judgement can provide for an idea of the reason, not a
schema of the sensibility, but a law, though only as to its form as
law; such a law, however, as can be exhibited in concreto in objects
of the senses, and therefore a law of nature. We can therefore call
this law the type of the moral law.

The rule of the judgement according to laws of pure practical reason
is this: ask yourself whether, if the action you propose were to
take place by a law of the system of nature of which you were yourself
a part, you could regard it as possible by your own will. Everyone
does, in fact, decide by this rule whether actions are morally good or
evil. Thus, people say: "If everyone permitted himself to deceive,
when he thought it to his advantage; or thought himself justified in
shortening his life as soon as he was thoroughly weary of it; or
looked with perfect indifference on the necessity of others; and if
you belonged to such an order of things, would you do so with the
assent of your own will? " Now everyone knows well that if he
secretly allows himself to deceive, it does not follow that everyone
else does so; or if, unobserved, he is destitute of compassion, others
would not necessarily be so to him; hence, this comparison of the
maxim of his actions with a universal law of nature is not the
determining principle of his will. Such a law is, nevertheless, a type
of the estimation of the maxim on moral principles. If the maxim of
the action is not such as to stand the test of the form of a universal
law of nature, then it is morally impossible. This is the judgement
even of common sense; for its ordinary judgements, even those of
experience, are always based on the law of nature. It has it therefore
always at hand, only that in cases where causality from freedom is
to be criticised, it makes that law of nature only the type of a law
of freedom, because, without something which it could use as an
example in a case of experience, it could not give the law of a pure
practical reason its proper use in practice.

It is therefore allowable to use the system of the world of sense as
the type of a supersensible system of things, provided I do not
transfer to the latter the intuitions, and what depends on them, but
merely apply to it the form of law in general (the notion of which
occurs even in the commonest use of reason, but cannot be definitely
known a priori for any other purpose than the pure practical use of
reason); for laws, as such, are so far identical, no matter from
what they derive their determining principles.

{BOOK_1|CHAPTER_2 ^paragraph 50}

Further, since of all the supersensible absolutely nothing [is
known] except freedom (through the moral law), and this only so far as
it is inseparably implied in that law, and moreover all
supersensible objects to which reason might lead us, following the
guidance of that law, have still no reality for us, except for the
purpose of that law, and for the use of mere practical reason; and
as reason is authorized and even compelled to use physical nature
(in its pure form as an object of the understanding) as the type of
the judgement; hence, the present remark will serve to guard against
reckoning amongst concepts themselves that which belongs only to the
typic of concepts. This, namely, as a typic of the judgement, guards
against the empiricism of practical reason, which founds the practical
notions of good and evil merely on experienced consequences (so-called
happiness). No doubt happiness and the infinite advantages which would
result from a will determined by self-love, if this will at the same
time erected itself into a universal law of nature, may certainly
serve as a perfectly suitable type of the morally good, but it is
not identical with it.