CHAPTER I. Of the Principles of Pure Practical Reason.

Produced by Matthew Stapleton

1788

THE CRITIQUE OF PRACTICAL REASON

by Immanuel Kant

translated by Thomas Kingsmill Abbott

PREFACE.

This work is called the Critique of Practical Reason, not of the

pure practical reason, although its parallelism with the speculative

critique would seem to require the latter term. The reason of this

appears sufficiently from the treatise itself. Its business is to show

that there is pure practical reason, and for this purpose it

criticizes the entire practical faculty of reason. If it succeeds in

this, it has no need to criticize the pure faculty itself in order

to see whether reason in making such a claim does not presumptuously

overstep itself (as is the case with the speculative reason). For

if, as pure reason, it is actually practical, it proves its own

reality and that of its concepts by fact, and all disputation

against the possibility of its being real is futile.

With this faculty, transcendental freedom is also established;

freedom, namely, in that absolute sense in which speculative reason

required it in its use of the concept of causality in order to

escape the antinomy into which it inevitably falls, when in the

chain of cause and effect it tries to think the unconditioned.

Speculative reason could only exhibit this concept (of freedom)

problematically as not impossible to thought, without assuring it

any objective reality, and merely lest the supposed impossibility of

what it must at least allow to be thinkable should endanger its very

being and plunge it into an abyss of scepticism.

Inasmuch as the reality of the concept of freedom is proved by an

apodeictic law of practical reason, it is the keystone of the whole

system of pure reason, even the speculative, and all other concepts

(those of God and immortality) which, as being mere ideas, remain in

it unsupported, now attach themselves to this concept, and by it

obtain consistence and objective reality; that is to say, their

possibility is proved by the fact that freedom actually exists, for

this idea is revealed by the moral law.

Freedom, however, is the only one of all the ideas of the

speculative reason of which we know the possibility a priori (without,

however, understanding it), because it is the condition of the moral

law which we know. * The ideas of God and immortality, however, are

not conditions of the moral law, but only conditions of the necessary

object of a will determined by this law; that is to say, conditions of

the practical use of our pure reason. Hence, with respect to these

ideas, we cannot affirm that we know and understand, I will not say

the actuality, but even the possibility of them. However they are

the conditions of the application of the morally determined will to

its object, which is given to it a priori, viz., the summum bonum.

Consequently in this practical point of view their possibility must be

assumed, although we cannot theoretically know and understand it. To

justify this assumption it is sufficient, in a practical point of

view, that they contain no intrinsic impossibility (contradiction).

Here we have what, as far as speculative reason is concerned, is a

merely subjective principle of assent, which, however, is

objectively valid for a reason equally pure but practical, and this

principle, by means of the concept of freedom, assures objective

reality and authority to the ideas of God and immortality. Nay,

there is a subjective necessity (a need of pure reason) to assume

them. Nevertheless the theoretical knowledge of reason is not hereby

enlarged, but only the possibility is given, which heretofore was

merely a problem and now becomes assertion, and thus the practical use

of reason is connected with the elements of theoretical reason. And

this need is not a merely hypothetical one for the arbitrary

purposes of speculation, that we must assume something if we wish in

speculation to carry reason to its utmost limits, but it is a need

which has the force of law to assume something without which that

cannot be which we must inevitably set before us as the aim of our

action.

{PREFACE ^paragraph 5}

* Lest any one should imagine that he finds an inconsistency here

when I call freedom the condition of the moral law, and hereafter

maintain in the treatise itself that the moral law is the condition

under which we can first become conscious of freedom, I will merely

remark that freedom is the ratio essendi of the moral law, while the

moral law is the ratio cognoscendi of freedom. For had not the moral

law been previously distinctly thought in our reason, we should

never consider ourselves justified in assuming such a thing as

freedom, although it be not contradictory. But were there no freedom

it would be impossible to trace the moral law in ourselves at all.

It would certainly be more satisfactory to our speculative reason if

it could solve these problems for itself without this circuit and

preserve the solution for practical use as a thing to be referred

to, but in fact our faculty of speculation is not so well provided.

Those who boast of such high knowledge ought not to keep it back,

but to exhibit it publicly that it may be tested and appreciated. They

want to prove: very good, let them prove; and the critical

philosophy lays its arms at their feet as the victors. Quid statis?

Nolint. Atqui licet esse beatis. As they then do not in fact choose to

do so, probably because they cannot, we must take up these arms

again in order to seek in the mortal use of reason, and to base on

this, the notions of God, freedom, and immortality, the possibility of

which speculation cannot adequately prove.

Here first is explained the enigma of the critical philosophy, viz.:

how we deny objective reality to the supersensible use of the

categories in speculation and yet admit this reality with respect to

the objects of pure practical reason. This must at first seem

inconsistent as long as this practical use is only nominally known.

But when, by a thorough analysis of it, one becomes aware that the

reality spoken of does not imply any theoretical determination of

the categories and extension of our knowledge to the supersensible;

but that what is meant is that in this respect an object belongs to

them, because either they are contained in the necessary determination

of the will a priori, or are inseparably connected with its object;

then this inconsistency disappears, because the use we make of these

concepts is different from what speculative reason requires. On the

other hand, there now appears an unexpected and very satisfactory

proof of the consistency of the speculative critical philosophy. For

whereas it insisted that the objects of experience as such,

including our own subject, have only the value of phenomena, while

at the same time things in themselves must be supposed as their basis,

so that not everything supersensible was to be regarded as a fiction

and its concept as empty; so now practical reason itself, without

any concert with the speculative, assures reality to a supersensible

object of the category of causality, viz., freedom, although (as

becomes a practical concept) only for practical use; and this

establishes on the evidence of a fact that which in the former case

could only be conceived. By this the strange but certain doctrine of

the speculative critical philosophy, that the thinking subject is to

itself in internal intuition only a phenomenon, obtains in the

critical examination of the practical reason its full confirmation,

and that so thoroughly that we should be compelled to adopt this

doctrine, even if the former had never proved it at all. *

{PREFACE ^paragraph 10}

* The union of causality as freedom with causality as rational

mechanism, the former established by the moral law, the latter by

the law of nature in the same subject, namely, man, is impossible,

unless we conceive him with reference to the former as a being in

himself, and with reference to the latter as a phenomenon- the

former in pure consciousness, the latter in empirical consciousness.

Otherwise reason inevitably contradicts itself.

By this also I can understand why the most considerable objections

which I have as yet met with against the Critique turn about these two

points, namely, on the one side, the objective reality of the

categories as applied to noumena, which is in the theoretical

department of knowledge denied, in the practical affirmed; and on

the other side, the paradoxical demand to regard oneself qua subject

of freedom as a noumenon, and at the same time from the point of

view of physical nature as a phenomenon in one's own empirical

consciousness; for as long as one has formed no definite notions of

morality and freedom, one could not conjecture on the one side what

was intended to be the noumenon, the basis of the alleged

phenomenon, and on the other side it seemed doubtful whether it was at

all possible to form any notion of it, seeing that we had previously

assigned all the notions of the pure understanding in its

theoretical use exclusively to phenomena. Nothing but a detailed

criticism of the practical reason can remove all this

misapprehension and set in a clear light the consistency which

constitutes its greatest merit.

So much by way of justification of the proceeding by which, in

this work, the notions and principles of pure speculative reason which

have already undergone their special critical examination are, now and

then, again subjected to examination. This would not in other cases be

in accordance with the systematic process by which a science is

established, since matters which have been decided ought only to be

cited and not again discussed. In this case, however, it was not

only allowable but necessary, because reason is here considered in

transition to a different use of these concepts from what it had

made of them before. Such a transition necessitates a comparison of

the old and the new usage, in order to distinguish well the new path

from the old one and, at the same time, to allow their connection to

be observed. Accordingly considerations of this kind, including

those which are once more directed to the concept of freedom in the

practical use of the pure reason, must not be regarded as an

interpolation serving only to fill up the gaps in the critical

system of speculative reason (for this is for its own purpose

complete), or like the props and buttresses which in a hastily

constructed building are often added afterwards; but as true members

which make the connexion of the system plain, and show us concepts,

here presented as real, which there could only be presented

problematically. This remark applies especially to the concept of

freedom, respecting which one cannot but observe with surprise that so

many boast of being able to understand it quite well and to explain

its possibility, while they regard it only psychologically, whereas if

they had studied it in a transcendental point of view, they must

have recognized that it is not only indispensable as a problematical

concept, in the complete use of speculative reason, but also quite

incomprehensible; and if they afterwards came to consider its

practical use, they must needs have come to the very mode of

determining the principles of this, to which they are now so loth to

assent. The concept of freedom is the stone of stumbling for all

empiricists, but at the same time the key to the loftiest practical

principles for critical moralists, who perceive by its means that they

must necessarily proceed by a rational method. For this reason I beg

the reader not to pass lightly over what is said of this concept at

the end of the Analytic.

I must leave it to those who are acquainted with works of this

kind to judge whether such a system as that of the practical reason,

which is here developed from the critical examination of it, has

cost much or little trouble, especially in seeking not to miss the

true point of view from which the whole can be rightly sketched. It

presupposes, indeed, the Fundamental Principles of the Metaphysic of

Morals, but only in so far as this gives a preliminary acquaintance

with the principle of duty, and assigns and justifies a definite

formula thereof; in other respects it is independent. * It results

from the nature of this practical faculty itself that the complete

classification of all practical sciences cannot be added, as in the

critique of the speculative reason. For it is not possible to define

duties specially, as human duties, with a view to their

classification, until the subject of this definition (viz., man) is

known according to his actual nature, at least so far as is

necessary with respect to duty; this, however, does not belong to a

critical examination of the practical reason, the business of which is

only to assign in a complete manner the principles of its possibility,

extent, and limits, without special reference to human nature. The

classification then belongs to the system of science, not to the

system of criticism.

{PREFACE ^paragraph 15}

* A reviewer who wanted to find some fault with this work has hit

the truth better, perhaps, than he thought, when he says that no new

principle of morality is set forth in it, but only a new formula.

But who would think of introducing a new principle of all morality and

making himself as it were the first discoverer of it, just as if all

the world before him were ignorant what duty was or had been in

thorough-going error? But whoever knows of what importance to a

mathematician a formula is, which defines accurately what is to be

done to work a problem, will not think that a formula is insignificant

and useless which does the same for all duty in general.

In the second part of the Analytic I have given, as I trust, a

sufficient answer to the objection of a truth-loving and acute

critic * of the Fundamental Principles of the Metaphysic of Morals- a

critic always worthy of respect- the objection, namely, that the

notion of good was not established before the moral principle, as he

thinks it ought to have been. *(2) I have also had regard to many of

the objections which have reached me from men who show that they have

at heart the discovery of the truth, and I shall continue to do so

(for those who have only their old system before their eyes, and who

have already settled what is to be approved or disapproved, do not

desire any explanation which might stand in the way of their own

private opinion.)

{PREFACE ^paragraph 20}

* [See Kant's "Das mag in der Theoric ricktig seyn," etc. Werke,

vol. vii, p. 182.]

*(2) It might also have been objected to me that I have not first

defined the notion of the faculty of desire, or of the feeling of

Pleasure, although this reproach would be unfair, because this

definition might reasonably be presupposed as given in psychology.

However, the definition there given might be such as to found the

determination of the faculty of desire on the feeling of pleasure

(as is commonly done), and thus the supreme principle of practical

philosophy would be necessarily made empirical, which, however,

remains to be proved and in this critique is altogether refuted. It

will, therefore, give this definition here in such a manner as it

ought to be given, in order to leave this contested point open at

the beginning, as it should be. LIFE is the faculty a being has of

acting according to laws of the faculty of desire. The faculty of

DESIRE is the being's faculty of becoming by means of its ideas the

cause of the actual existence of the objects of these ideas.

PLEASURE is the idea of the agreement of the object, or the action

with the subjective conditions of life, i.e., with the faculty of

causality of an idea in respect of the actuality of its object (or

with the determination of the forces of the subject to action which

produces it). I have no further need for the purposes of this critique

of notions borrowed from psychology; the critique itself supplies

the rest. It is easily seen that the question whether the faculty of

desire is always based on pleasure, or whether under certain

conditions pleasure only follows the determination of desire, is by

this definition left undecided, for it is composed only of terms

belonging to the pure understanding, i.e., of categories which contain

nothing empirical. Such precaution is very desirable in all philosophy

and yet is often neglected; namely, not to prejudge questions by

adventuring definitions before the notion has been completely

analysed, which is often very late. It may be observed through the

whole course of the critical philosophy (of the theoretical as well as

the practical reason) that frequent opportunity offers of supplying

defects in the old dogmatic method of philosophy, and of correcting

errors which are not observed until we make such rational use of these

notions viewing them as a whole.

When we have to study a particular faculty of the human mind in

its sources, its content, and its limits; then from the nature of

human knowledge we must begin with its parts, with an accurate and

complete exposition of them; complete, namely, so far as is possible

in the present state of our knowledge of its elements. But there is

another thing to be attended to which is of a more philosophical and

architectonic character, namely, to grasp correctly the idea of the

whole, and from thence to get a view of all those parts as mutually

related by the aid of pure reason, and by means of their derivation

from the concept of the whole. This is only possible through the

most intimate acquaintance with the system; and those who find the

first inquiry too troublesome, and do not think it worth their while

to attain such an acquaintance, cannot reach the second stage, namely,

the general view, which is a synthetical return to that which had

previously been given analytically. It is no wonder then if they

find inconsistencies everywhere, although the gaps which these

indicate are not in the system itself, but in their own incoherent

train of thought.

I have no fear, as regards this treatise, of the reproach that I

wish to introduce a new language, since the sort of knowledge here

in question has itself somewhat of an everyday character. Nor even

in the case of the former critique could this reproach occur to anyone

who had thought it through and not merely turned over the leaves. To

invent new words where the language has no lack of expressions for

given notions is a childish effort to distinguish oneself from the

crowd, if not by new and true thoughts, yet by new patches on the

old garment. If, therefore, the readers of that work know any more

familiar expressions which are as suitable to the thought as those

seem to me to be, or if they think they can show the futility of these

thoughts themselves and hence that of the expression, they would, in

the first case, very much oblige me, for I only desire to be

understood: and, in the second case, they would deserve well of

philosophy. But, as long as these thoughts stand, I very much doubt

that suitable and yet more common expressions for them can be found. *

{PREFACE ^paragraph 25}

* I am more afraid in the present treatise of occasional

misconception in respect of some expressions which I have chosen

with the greatest care in order that the notion to which they point

may not be missed. Thus, in the table of categories of the Practical

reason under the title of Modality, the Permitted, and forbidden (in a

practical objective point of view, possible and impossible) have

almost the same meaning in common language as the next category,

duty and contrary to duty. Here, however, the former means what

coincides with, or contradicts, a merely possible practical precept

(for example, the solution of all problems of geometry and mechanics);

the latter, what is similarly related to a law actually present in the

reason; and this distinction is not quite foreign even to common

language, although somewhat unusual. For example, it is forbidden to

an orator, as such, to forge new words or constructions; in a

certain degree this is permitted to a poet; in neither case is there

any question of duty. For if anyone chooses to forfeit his

reputation as an orator, no one can prevent him. We have here only

to do with the distinction of imperatives into problematical,

assertorial, and apodeictic. Similarly in the note in which I have

pared the moral ideas of practical perfection in different

philosophical schools, I have distinguished the idea of wisdom from

that of holiness, although I have stated that essentially and

objectively they are the same. But in that place I understand by the

former only that wisdom to which man (the Stoic) lays claim; therefore

I take it subjectively as an attribute alleged to belong to man.

(Perhaps the expression virtue, with which also the Stoic made great show,

would better mark the characteristic of his school.) The expression of

a postulate of pure practical reason might give most occasion to

misapprehension in case the reader confounded it with the

signification of the postulates in pure mathematics, which carry

apodeictic certainty with them. These, however, postulate the

possibility of an action, the object of which has been previously

recognized a priori in theory as possible, and that with perfect

certainty. But the former postulates the possibility of an object

itself (God and the immortality of the soul) from apodeictic practical

laws, and therefore only for the purposes of a practical reason.

This certainty of the postulated possibility then is not at all

theoretic, and consequently not apodeictic; that is to say, it is

not a known necessity as regards the object, but a necessary

supposition as regards the subject, necessary for the obedience to its

objective but practical laws. It is, therefore, merely a necessary

hypothesis. I could find no better expression for this rational

necessity, which is subjective, but yet true and unconditional.

In this manner, then, the a priori principles of two faculties of

the mind, the faculty of cognition and that of desire, would be

found and determined as to the conditions, extent, and limits of their

use, and thus a sure foundation be paid for a scientific system of

philosophy, both theoretic and practical.

Nothing worse could happen to these labours than that anyone

should make the unexpected discovery that there neither is, nor can

be, any a priori knowledge at all. But there is no danger of this.

This would be the same thing as if one sought to prove by reason

that there is no reason. For we only say that we know something by

reason, when we are conscious that we could have known it, even if

it had not been given to us in experience; hence rational knowledge

and knowledge a priori are one and the same. It is a clear

contradiction to try to extract necessity from a principle of

experience (ex pumice aquam), and to try by this to give a judgement

true universality (without which there is no rational inference, not

even inference from analogy, which is at least a presumed universality

and objective necessity). To substitute subjective necessity, that is,

custom, for objective, which exists only in a priori judgements, is to

deny to reason the power of judging about the object, i.e., of knowing

it, and what belongs to it. It implies, for example, that we must

not say of something which often or always follows a certain

antecedent state that we can conclude from this to that (for this

would imply objective necessity and the notion of an a priori

connexion), but only that we may expect similar cases (just as animals

do), that is that we reject the notion of cause altogether as false

and a mere delusion. As to attempting to remedy this want of objective

and consequently universal validity by saying that we can see no

ground for attributing any other sort of knowledge to other rational

beings, if this reasoning were valid, our ignorance would do more

for the enlargement of our knowledge than all our meditation. For,

then, on this very ground that we have no knowledge of any other

rational beings besides man, we should have a right to suppose them to

be of the same nature as we know ourselves to be: that is, we should

really know them. I omit to mention that universal assent does not

prove the objective validity of a judgement (i.e., its validity as a

cognition), and although this universal assent should accidentally

happen, it could furnish no proof of agreement with the object; on the

contrary, it is the objective validity which alone constitutes the

basis of a necessary universal consent.

{PREFACE ^paragraph 30}

Hume would be quite satisfied with this system of universal

empiricism, for, as is well known, he desired nothing more than

that, instead of ascribing any objective meaning to the necessity in

the concept of cause, a merely subjective one should be assumed, viz.,

custom, in order to deny that reason could judge about God, freedom,

and immortality; and if once his principles were granted, he was

certainly well able to deduce his conclusions therefrom, with all

logical coherence. But even Hume did not make his empiricism so

universal as to include mathematics. He holds the principles of

mathematics to be analytical; and if his were correct, they would

certainly be apodeictic also: but we could not infer from this that

reason has the faculty of forming apodeictic judgements in

philosophy also- that is to say, those which are synthetical

judgements, like the judgement of causality. But if we adopt a

universal empiricism, then mathematics will be included.

Now if this science is in contradiction with a reason that admits

only empirical principles, as it inevitably is in the antinomy in

which mathematics prove the infinite divisibility of space, which

empiricism cannot admit; then the greatest possible evidence of

demonstration is in manifest contradiction with the alleged

conclusions from experience, and we are driven to ask, like

Cheselden's blind patient, "Which deceives me, sight or touch?" (for

empiricism is based on a necessity felt, rationalism on a necessity

seen). And thus universal empiricism reveals itself as absolute

scepticism. It is erroneous to attribute this in such an unqualified

sense to Hume, * since he left at least one certain touchstone (which

can only be found in a priori principles), although experience

consists not only of feelings, but also of judgements.

* Names that designate the followers of a sect have always been

accompanied with much injustice; just as if one said, "N is an

Idealist." For although he not only admits, but even insists, that our

ideas of external things have actual objects of external things

corresponding to them, yet he holds that the form of the intuition

does not depend on them but on the human mind.

{PREFACE ^paragraph 35}

However, as in this philosophical and critical age such empiricism

can scarcely be serious, and it is probably put forward only as an

intellectual exercise and for the purpose of putting in a clearer

light, by contrast, the necessity of rational a priori principles,

we can only be grateful to those who employ themselves in this

otherwise uninstructive labour.

INTRODUCTION

INTRODUCTION.

Of the Idea of a Critique of Practical Reason.

The theoretical use of reason was concerned with objects of the

cognitive faculty only, and a critical examination of it with

reference to this use applied properly only to the pure faculty of

cognition; because this raised the suspicion, which was afterwards

confirmed, that it might easily pass beyond its limits, and be lost

among unattainable objects, or even contradictory notions. It is quite

different with the practical use of reason. In this, reason is

concerned with the grounds of determination of the will, which is a

faculty either to produce objects corresponding to ideas, or to

determine ourselves to the effecting of such objects (whether the

physical power is sufficient or not); that is, to determine our

causality. For here, reason can at least attain so far as to determine

the will, and has always objective reality in so far as it is the

volition only that is in question. The first question here then is

whether pure reason of itself alone suffices to determine the will, or

whether it can be a ground of determination only as dependent on

empirical conditions. Now, here there comes in a notion of causality

justified by the critique of the pure reason, although not capable

of being presented empirically, viz., that of freedom; and if we can

now discover means of proving that this property does in fact belong

to the human will (and so to the will of all rational beings), then it

will not only be shown that pure reason can be practical, but that

it alone, and not reason empirically limited, is indubitably

practical; consequently, we shall have to make a critical examination,

not of pure practical reason, but only of practical reason

generally. For when once pure reason is shown to exist, it needs no

critical examination. For reason itself contains the standard for

the critical examination of every use of it. The critique, then, of

practical reason generally is bound to prevent the empirically

conditioned reason from claiming exclusively to furnish the ground

of determination of the will. If it is proved that there is a

[practical] reason, its employment is alone immanent; the

empirically conditioned use, which claims supremacy, is on the

contrary transcendent and expresses itself in demands and precepts

which go quite beyond its sphere. This is just the opposite of what

might be said of pure reason in its speculative employment.

However, as it is still pure reason, the knowledge of which is

here the foundation of its practical employment, the general outline

of the classification of a critique of practical reason must be

arranged in accordance with that of the speculative. We must, then,

have the Elements and the Methodology of it; and in the former an

Analytic as the rule of truth, and a Dialectic as the exposition and

dissolution of the illusion in the judgements of practical reason. But

the order in the subdivision of the Analytic will be the reverse of

that in the critique of the pure speculative reason. For, in the

present case, we shall commence with the principles and proceed to the

concepts, and only then, if possible, to the senses; whereas in the

case of the speculative reason we began with the senses and had to end

with the principles. The reason of this lies again in this: that now

we have to do with a will, and have to consider reason, not in its

relation to objects, but to this will and its causality. We must,

then, begin with the principles of a causality not empirically

conditioned, after which the attempt can be made to establish our

notions of the determining grounds of such a will, of their

application to objects, and finally to the subject and its sense

faculty. We necessarily begin with the law of causality from

freedom, that is, with a pure practical principle, and this determines

the objects to which alone it can be applied.

BOOK_1|CHAPTER_1

FIRST PART.

ELEMENTS OF PURE PRACTICAL REASON.

BOOK I. The Analytic of Pure Practical Reason.

CHAPTER I. Of the Principles of Pure Practical Reason.

{BOOK_1|CHAPTER_1 ^paragraph 5}

I. DEFINITION.

Practical principles are propositions which contain a general

determination of the will, having under it several practical rules.

They are subjective, or maxims, when the condition is regarded by

the subject as valid only for his own will, but are objective, or

practical laws, when the condition is recognized as objective, that

is, valid for the will of every rational being.

{BOOK_1|CHAPTER_1 ^paragraph 10}

REMARK.

Supposing that pure reason contains in itself a practical motive,

that is, one adequate to determine the will, then there are

practical laws; otherwise all practical principles will be mere

maxims. In case the will of a rational being is pathologically

affected, there may occur a conflict of the maxims with the

practical laws recognized by itself. For example, one may make it

his maxim to let no injury pass unrevenged, and yet he may see that

this is not a practical law, but only his own maxim; that, on the

contrary, regarded as being in one and the same maxim a rule for the

will of every rational being, it must contradict itself. In natural

philosophy the principles of what happens, (e.g., the principle of

equality of action and reaction in the communication of motion) are at

the same time laws of nature; for the use of reason there is

theoretical and determined by the nature of the object. In practical

philosophy, i.e., that which has to do only with the grounds of

determination of the will, the principles which a man makes for

himself are not laws by which one is inevitably bound; because

reason in practical matters has to do with the subject, namely, with

the faculty of desire, the special character of which may occasion

variety in the rule. The practical rule is always a product of reason,

because it prescribes action as a means to the effect. But in the case

of a being with whom reason does not of itself determine the will,

this rule is an imperative, i.e., a rule characterized by "shall,"

which expresses the objective necessitation of the action and

signifies that, if reason completely determined the will, the action

would inevitably take place according to this rule. Imperatives,

therefore, are objectively valid, and are quite distinct from

maxims, which are subjective principles. The former either determine

the conditions of the causality of the rational being as an

efficient cause, i.e., merely in reference to the effect and the means

of attaining it; or they determine the will only, whether it is

adequate to the effect or not. The former would be hypothetical

imperatives, and contain mere precepts of skill; the latter, on the

contrary, would be categorical, and would alone be practical laws.

Thus maxims are principles, but not imperatives. Imperatives

themselves, however, when they are conditional (i.e., do not determine

the will simply as will, but only in respect to a desired effect, that

is, when they are hypothetical imperatives), are practical precepts

but not laws. Laws must be sufficient to determine the will as will,

even before I ask whether I have power sufficient for a desired

effect, or the means necessary to produce it; hence they are

categorical: otherwise they are not laws at all, because the necessity

is wanting, which, if it is to be practical, must be independent of

conditions which are pathological and are therefore only

contingently connected with the will. Tell a man, for example, that he

must be industrious and thrifty in youth, in order that he may not

want in old age; this is a correct and important practical precept

of the will. But it is easy to see that in this case the will is

directed to something else which it is presupposed that it desires;

and as to this desire, we must leave it to the actor himself whether

he looks forward to other resources than those of his own acquisition,

or does not expect to be old, or thinks that in case of future

necessity he will be able to make shift with little. Reason, from

which alone can spring a rule involving necessity, does, indeed,

give necessity to this precept (else it would not be an imperative),

but this is a necessity dependent on subjective conditions, and cannot

be supposed in the same degree in all subjects. But that reason may

give laws it is necessary that it should only need to presuppose

itself, because rules are objectively and universally valid only

when they hold without any contingent subjective conditions, which

distinguish one rational being from another. Now tell a man that he

should never make a deceitful promise, this is a rule which only

concerns his will, whether the purposes he may have can be attained

thereby or not; it is the volition only which is to be determined a

priori by that rule. If now it is found that this rule is

practically right, then it is a law, because it is a categorical

imperative. Thus, practical laws refer to the will only, without

considering what is attained by its causality, and we may disregard

this latter (as belonging to the world of sense) in order to have them

quite pure.

II. THEOREM I.

{BOOK_1|CHAPTER_1 ^paragraph 15}

All practical principles which presuppose an object (matter) of

the faculty of desire as the ground of determination of the will are

empirical and can furnish no practical laws.

By the matter of the faculty of desire I mean an object the

realization of which is desired. Now, if the desire for this object

precedes the practical rule and is the condition of our making it a

principle, then I say (in the first place) this principle is in that

case wholly empirical, for then what determines the choice is the idea

of an object and that relation of this idea to the subject by which

its faculty of desire is determined to its realization. Such a

relation to the subject is called the pleasure in the realization of

an object. This, then, must be presupposed as a condition of the

possibility of determination of the will. But it is impossible to know

a priori of any idea of an object whether it will be connected with

pleasure or pain, or be indifferent. In such cases, therefore, the

determining principle of the choice must be empirical and,

therefore, also the practical material principle which presupposes

it as a condition.

In the second place, since susceptibility to a pleasure or pain

can be known only empirically and cannot hold in the same degree for

all rational beings, a principle which is based on this subjective

condition may serve indeed as a maxim for the subject which

possesses this susceptibility, but not as a law even to him (because

it is wanting in objective necessity, which must be recognized a

priori); it follows, therefore, that such a principle can never

furnish a practical law.

{BOOK_1|CHAPTER_1 ^paragraph 20}

III. THEOREM II.

All material practical principles as such are of one and the same

kind and come under the general principle of self-love or private

happiness.

Pleasure arising from the idea of the idea of the existence of a

thing, in so far as it is to determine the desire of this thing, is

founded on the susceptibility of the subject, since it depends on

the presence of an object; hence it belongs to sense (feeling), and

not to understanding, which expresses a relation of the idea to an

object according to concepts, not to the subject according to

feelings. It is, then, practical only in so far as the faculty of

desire is determined by the sensation of agreeableness which the

subject expects from the actual existence of the object. Now, a

rational being's consciousness of the pleasantness of life

uninterruptedly accompanying his whole existence is happiness; and the

principle which makes this the supreme ground of determination of

the will is the principle of self-love. All material principles, then,

which place the determining ground of the will in the pleasure or pain

to be received from the existence of any object are all of the same

kind, inasmuch as they all belong to the principle of self-love or

private happiness.

{BOOK_1|CHAPTER_1 ^paragraph 25}

COROLLARY.

All material practical rules place the determining principle of

the will in the lower desires; and if there were no purely formal laws

of the will adequate to determine it, then we could not admit any

higher desire at all.

REMARK I.

{BOOK_1|CHAPTER_1 ^paragraph 30}

It is surprising that men, otherwise acute, can think it possible to

distinguish between higher and lower desires, according as the ideas

which are connected with the feeling of pleasure have their origin

in the senses or in the understanding; for when we inquire what are

the determining grounds of desire, and place them in some expected

pleasantness, it is of no consequence whence the idea of this pleasing

object is derived, but only how much it pleases. Whether an idea has

its seat and source in the understanding or not, if it can only

determine the choice by presupposing a feeling of pleasure in the

subject, it follows that its capability of determining the choice

depends altogether on the nature of the inner sense, namely, that this

can be agreeably affected by it. However dissimilar ideas of objects

may be, though they be ideas of the understanding, or even of the

reason in contrast to ideas of sense, yet the feeling of pleasure,

by means of which they constitute the determining principle of the

will (the expected satisfaction which impels the activity to the

production of the object), is of one and the same kind, not only

inasmuch as it can only be known empirically, but also inasmuch as

it affects one and the same vital force which manifests itself in

the faculty of desire, and in this respect can only differ in degree

from every other ground of determination. Otherwise, how could we

compare in respect of magnitude two principles of determination, the

ideas of which depend upon different faculties, so as to prefer that

which affects the faculty of desire in the highest degree. The same

man may return unread an instructive book which he cannot again

obtain, in order not to miss a hunt; he may depart in the midst of a

fine speech, in order not to be late for dinner; he may leave a

rational conversation, such as he otherwise values highly, to take his

place at the gaming-table; he may even repulse a poor man whom he at

other times takes pleasure in benefiting, because he has only just

enough money in his pocket to pay for his admission to the theatre. If

the determination of his will rests on the feeling of the

agreeableness or disagreeableness that he expects from any cause, it

is all the same to him by what sort of ideas he will be affected.

The only thing that concerns him, in order to decide his choice, is,

how great, how long continued, how easily obtained, and how often

repeated, this agreeableness is. Just as to the man who wants money to

spend, it is all the same whether the gold was dug out of the mountain

or washed out of the sand, provided it is everywhere accepted at the

same value; so the man who cares only for the enjoyment of life does

not ask whether the ideas are of the understanding or the senses,

but only how much and how great pleasure they will give for the

longest time. It is only those that would gladly deny to pure reason

the power of determining the will, without the presupposition of any

feeling, who could deviate so far from their own exposition as to

describe as quite heterogeneous what they have themselves previously

brought under one and the same principle. Thus, for example, it is

observed that we can find pleasure in the mere exercise of power, in

the consciousness of our strength of mind in overcoming obstacles

which are opposed to our designs, in the culture of our mental

talents, etc.; and we justly call these more refined pleasures and

enjoyments, because they are more in our power than others; they do

not wear out, but rather increase the capacity for further enjoyment

of them, and while they delight they at the same time cultivate. But

to say on this account that they determine the will in a different way

and not through sense, whereas the possibility of the pleasure

presupposes a feeling for it implanted in us, which is the first

condition of this satisfaction; this is just as when ignorant

persons that like to dabble in metaphysics imagine matter so subtle,

so supersubtle that they almost make themselves giddy with it, and

then think that in this way they have conceived it as a spiritual

and yet extended being. If with Epicurus we make virtue determine

the will only by means of the pleasure it promises, we cannot

afterwards blame him for holding that this pleasure is of the same

kind as those of the coarsest senses. For we have no reason whatever

to charge him with holding that the ideas by which this feeling is

excited in us belong merely to the bodily senses. As far as can be

conjectured, he sought the source of many of them in the use of the

higher cognitive faculty, but this did not prevent him, and could

not prevent him, from holding on the principle above stated, that

the pleasure itself which those intellectual ideas give us, and by

which alone they can determine the will, is just of the same kind.

Consistency is the highest obligation of a philosopher, and yet the

most rarely found. The ancient Greek schools give us more examples

of it than we find in our syncretistic age, in which a certain shallow

and dishonest system of compromise of contradictory principles is

devised, because it commends itself better to a public which is

content to know something of everything and nothing thoroughly, so

as to please every party.

The principle of private happiness, however much understanding and

reason may be used in it, cannot contain any other determining

principles for the will than those which belong to the lower

desires; and either there are no [higher] desires at all, or pure

reason must of itself alone be practical; that is, it must be able

to determine the will by the mere form of the practical rule without

supposing any feeling, and consequently without any idea of the

pleasant or unpleasant, which is the matter of the desire, and which

is always an empirical condition of the principles. Then only, when

reason of itself determines the will (not as the servant of the

inclination), it is really a higher desire to which that which is

pathologically determined is subordinate, and is really, and even

specifically, distinct from the latter, so that even the slightest

admixture of the motives of the latter impairs its strength and

superiority; just as in a mathematical demonstration the least

empirical condition would degrade and destroy its force and value.

Reason, with its practical law, determines the will immediately, not

by means of an intervening feeling of pleasure or pain, not even of

pleasure in the law itself, and it is only because it can, as pure

reason, be practical, that it is possible for it to be legislative.

REMARK II.

{BOOK_1|CHAPTER_1 ^paragraph 35}

To be happy is necessarily the wish of every finite rational

being, and this, therefore, is inevitably a determining principle of

its faculty of desire. For we are not in possession originally of

satisfaction with our whole existence- a bliss which would imply a

consciousness of our own independent self-sufficiency this is a

problem imposed upon us by our own finite nature, because we have

wants and these wants regard the matter of our desires, that is,

something that is relative to a subjective feeling of pleasure or

pain, which determines what we need in order to be satisfied with

our condition. But just because this material principle of

determination can only be empirically known by the subject, it is

impossible to regard this problem as a law; for a law being

objective must contain the very same principle of determination of the

will in all cases and for all rational beings. For, although the

notion of happiness is in every case the foundation of practical

relation of the objects to the desires, yet it is only a general

name for the subjective determining principles, and determines nothing

specifically; whereas this is what alone we are concerned with in this

practical problem, which cannot be solved at all without such specific

determination. For it is every man's own special feeling of pleasure

and pain that decides in what he is to place his happiness, and even

in the same subject this will vary with the difference of his wants

according as this feeling changes, and thus a law which is

subjectively necessary (as a law of nature) is objectively a very

contingent practical principle, which can and must be very different

in different subjects and therefore can never furnish a law; since, in

the desire for happiness it is not the form (of conformity to law)

that is decisive, but simply the matter, namely, whether I am to

expect pleasure in following the law, and how much. Principles of

self-love may, indeed, contain universal precepts of skill (how to

find means to accomplish one's purpose), but in that case they are

merely theoretical principles; * as, for example, how he who would

like to eat bread should contrive a mill; but practical precepts

founded on them can never be universal, for the determining principle

of the desire is based on the feeling pleasure and pain, which can

never be supposed to be universally directed to the same objects.

* Propositions which in mathematics or physics are called practical

ought properly to be called technical. For they have nothing to do

with the determination of the will; they only point out how a certain

effect is to be produced and are, therefore, just as theoretical as

any propositions which express the connection of a cause with an

effect. Now whoever chooses the effect must also choose the cause.

{BOOK_1|CHAPTER_1 ^paragraph 40}

Even supposing, however, that all finite rational beings were

thoroughly agreed as to what were the objects of their feelings of

pleasure and pain, and also as to the means which they must employ

to attain the one and avoid the other; still, they could by no means

set up the principle of self-love as a practical law, for this

unanimity itself would be only contingent. The principle of

determination would still be only subjectively valid and merely

empirical, and would not possess the necessity which is conceived in

every law, namely, an objective necessity arising from a priori

grounds; unless, indeed, we hold this necessity to be not at all

practical, but merely physical, viz., that our action is as inevitably

determined by our inclination, as yawning when we see others yawn.

It would be better to maintain that there are no practical laws at

all, but only counsels for the service of our desires, than to raise

merely subjective principles to the rank of practical laws, which have

objective necessity, and not merely subjective, and which must be

known by reason a priori, not by experience (however empirically

universal this may be). Even the rules of corresponding phenomena

are only called laws of nature (e.g., the mechanical laws), when we

either know them really a priori, or (as in the case of chemical laws)

suppose that they would be known a priori from objective grounds if

our insight reached further. But in the case of merely subjective

practical principles, it is expressly made a condition that they rest,

not on objective, but on subjective conditions of choice, and hence

that they must always be represented as mere maxims, never as

practical laws. This second remark seems at first sight to be mere

verbal refinement, but it defines the terms of the most important

distinction which can come into consideration in practical

investigations.

IV. THEOREM II.

A rational being cannot regard his maxims as practical universal

laws, unless he conceives them as principles which determine the will,

not by their matter, but by their form only.

{BOOK_1|CHAPTER_1 ^paragraph 45}

By the matter of a practical principle I mean the object of the

will. This object is either the determining ground of the will or it

is not. In the former case the rule of the will is subjected to an

empirical condition (viz., the relation of the determining idea to the

feeling of pleasure and pain), consequently it can not be a

practical law. Now, when we abstract from a law all matter, i.e.,

every object of the will (as a determining principle), nothing is left

but the mere form of a universal legislation. Therefore, either a

rational being cannot conceive his subjective practical principles,

that is, his maxims, as being at the same time universal laws, or he

must suppose that their mere form, by which they are fitted for

universal legislation, is alone what makes them practical laws.

REMARK.

The commonest understanding can distinguish without instruction what

form of maxim is adapted for universal legislation, and what is not.

Suppose, for example, that I have made it my maxim to increase my

fortune by every safe means. Now, I have a deposit in my hands, the

owner of which is dead and has left no writing about it. This is

just the case for my maxim. I desire then to know whether that maxim

can also bold good as a universal practical law. 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