INTRODUCTORY ETHICS

KANT'S FOUNDATIONS OF THE METAPHYSICS OF MORALS

There is therefore but one categorical imperative, namely, this: Act

only on that maxim whereby thou canst at the same time will that it

should become a universal law.

Now if all imperatives of duty can be deduced from this one

imperative as from their principle, then, although it should remain

undecided what is called duty is not merely a vain notion, yet at

least we shall be able to show what we understand by it and what

this notion means.

Since the universality of the law according to which effects are

produced constitutes what is properly called nature in the most

general sense (as to form), that is the existence of things so far

as it is determined by general laws, the imperative of duty may be

expressed thus: Act as if the maxim of thy action were to become by

thy will a universal law of nature.

We will now enumerate a few duties, adopting the usual division of

them into duties to ourselves and ourselves and to others, and into

perfect and imperfect duties.*

*It must be noted here that I reserve the division of duties for a

future metaphysic of morals; so that I give it here only as an

arbitrary one (in order to arrange my examples). For the rest, I

understand by a perfect duty one that admits no exception in favour of

inclination and then I have not merely external but also internal

perfect duties. This is contrary to the use of the word adopted in the

schools; but I do not intend to justify there, as it is all one for my

purpose whether it is admitted or not.

1. A man reduced to despair by a series of misfortunes feels wearied

of life, but is still so far in possession of his reason that he can

ask himself whether it would not be contrary to his duty to himself to

take his own life. Now he inquires whether the maxim of his action

could become a universal law of nature. His maxim is: "From

self-love I adopt it as a principle to shorten my life when its longer

duration is likely to bring more evil than satisfaction." It is

asked then simply whether this principle founded on self-love can

become a universal law of nature. Now we see at once that a system

of nature of which it should be a law to destroy life by means of

the very feeling whose special nature it is to impel to the

improvement of life would contradict itself and, therefore, could

not exist as a system of nature; hence that maxim cannot possibly

exist as a universal law of nature and, consequently, would be

wholly inconsistent with the supreme principle of all duty.

2. Another finds himself forced by necessity to borrow money. He

knows that he will not be able to repay it, but sees also that nothing

will be lent to him unless he promises stoutly to repay it in a

definite time. He desires to make this promise, but he has still so

much conscience as to ask himself: "Is it not unlawful and

inconsistent with duty to get out of a difficulty in this way?"

Suppose however that he resolves to do so: then the maxim of his

action would be expressed thus: "When I think myself in want of money,

I will borrow money and promise to repay it, although I know that I

never can do so." Now this principle of self-love or of one's own

advantage may perhaps be consistent with my whole future welfare;

but the question now is, "Is it right?" I change then the suggestion

of self-love into a universal law, and state the question thus: "How

would it be if my maxim were a universal law?" Then I see at once that

it could never hold as a universal law of nature, but would

necessarily contradict itself. For supposing it to be a universal

law that everyone when he thinks himself in a difficulty should be

able to promise whatever he pleases, with the purpose of not keeping

his promise, the promise itself would become impossible, as well as

the end that one might have in view in it, since no one would consider

that anything was promised to him, but would ridicule all such

statements as vain pretences.

3. A third finds in himself a talent which with the help of some

culture might make him a useful man in many respects. But he finds

himself in comfortable circumstances and prefers to indulge in

pleasure rather than to take pains in enlarging and improving his

happy natural capacities. He asks, however, whether his maxim of

neglect of his natural gifts, besides agreeing with his inclination to

indulgence, agrees also with what is called duty. He sees then that

a system of nature could indeed subsist with such a universal law

although men (like the South Sea islanders) should let their talents

rest and resolve to devote their lives merely to idleness,

amusement, and propagation of their species- in a word, to

enjoyment; but he cannot possibly will that this should be a universal

law of nature, or be implanted in us as such by a natural instinct.

For, as a rational being, he necessarily wills that his faculties be

developed, since they serve him and have been given him, for all sorts

of possible purposes.

4. A fourth, who is in prosperity, while he sees that others have to

contend with great wretchedness and that he could help them, thinks:

"What concern is it of mine? Let everyone be as happy as Heaven

pleases, or as be can make himself; I will take nothing from him nor

even envy him, only I do not wish to contribute anything to his

welfare or to his assistance in distress!" Now no doubt if such a mode

of thinking were a universal law, the human race might very well

subsist and doubtless even better than in a state in which everyone

talks of sympathy and good-will, or even takes care occasionally to

put it into practice, but, on the other side, also cheats when he can,

betrays the rights of men, or otherwise violates them. But although it

is possible that a universal law of nature might exist in accordance

with that maxim, it is impossible to will that such a principle should

have the universal validity of a law of nature. For a will which

resolved this would contradict itself, inasmuch as many cases might

occur in which one would have need of the love and sympathy of others,

and in which, by such a law of nature, sprung from his own will, he

would deprive himself of all hope of the aid he desires.

These are a few of the many actual duties, or at least what we

regard as such, which obviously fall into two classes on the one

principle that we have laid down. We must be able to will that a maxim

of our action should be a universal law. This is the canon of the

moral appreciation of the action generally. Some actions are of such a

character that their maxim cannot without contradiction be even

conceived as a universal law of nature, far from it being possible

that we should will that it should be so. In others this intrinsic

impossibility is not found, but still it is impossible to will that

their maxim should be raised to the universality of a law of nature,

since such a will would contradict itself It is easily seen that the

former violate strict or rigorous (inflexible) duty; the latter only

laxer (meritorious) duty. Thus it has been completely shown how all

duties depend as regards the nature of the obligation (not the

object of the action) on the same principle.

If now we attend to ourselves on occasion of any transgression of

duty, we shall find that we in fact do not will that our maxim

should be a universal law, for that is impossible for us; on the

contrary, we will that the opposite should remain a universal law,

only we assume the liberty of making an exception in our own favour or

(just for this time only) in favour of our inclination. Consequently

if we considered all cases from one and the same point of view,

namely, that of reason, we should find a contradiction in our own

will, namely, that a certain principle should be objectively necessary

as a universal law, and yet subjectively should not be universal,

but admit of exceptions. As however we at one moment regard our action

from the point of view of a will wholly conformed to reason, and

then again look at the same action from the point of view of a will

affected by inclination, there is not really any contradiction, but an

antagonism of inclination to the precept of reason, whereby the

universality of the principle is changed into a mere generality, so

that the practical principle of reason shall meet the maxim half

way. Now, although this cannot be justified in our own impartial

judgement, yet it proves that we do really recognise the validity of

the categorical imperative and (with all respect for it) only allow

ourselves a few exceptions, which we think unimportant and forced from

us.

We have thus established at least this much, that if duty is a

conception which is to have any import and real legislative

authority for our actions, it can only be expressed in categorical and

not at all in hypothetical imperatives. We have also, which is of

great importance, exhibited clearly and definitely for every practical

application the content of the categorical imperative, which must

contain the principle of all duty if there is such a thing at all.

We have not yet, however, advanced so far as to prove a priori that

there actually is such an imperative, that there is a practical law

which commands absolutely of itself and without any other impulse, and

that the following of this law is duty.

With the view of attaining to this, it is of extreme importance to

remember that we must not allow ourselves to think of deducing the

reality of this principle from the particular attributes of human

nature. For duty is to be a practical, unconditional necessity of

action; it must therefore hold for all rational beings (to whom an

imperative can apply at all), and for this reason only be also a law

for all human wills. On the contrary, whatever is deduced from the

particular natural characteristics of humanity, from certain

feelings and propensions, nay, even, if possible, from any

particular tendency proper to human reason, and which need not

necessarily hold for the will of every rational being; this may indeed

supply us with a maxim, but not with a law; with a subjective

principle on which we may have a propension and inclination to act,

but not with an objective principle on which we should be enjoined

to act, even though all our propensions, inclinations, and natural

dispositions were opposed to it. In fact, the sublimity and

intrinsic dignity of the command in duty are so much the more evident,

the less the subjective impulses favour it and the more they oppose

it, without being able in the slightest degree to weaken the

obligation of the law or to diminish its validity.

Here then we see philosophy brought to a critical position, since it

has to be firmly fixed, notwithstanding that it has nothing to support

it in heaven or earth. Here it must show its purity as absolute

director of its own laws, not the herald of those which are

whispered to it by an implanted sense or who knows what tutelary

nature. Although these may be better than nothing, yet they can

never afford principles dictated by reason, which must have their

source wholly a priori and thence their commanding authority,

expecting everything from the supremacy of the law and the due respect

for it, nothing from inclination, or else condemning the man to

self-contempt and inward abhorrence.

Thus every empirical element is not only quite incapable of being an

aid to the principle of morality, but is even highly prejudicial to

the purity of morals, for the proper and inestimable worth of an

absolutely good will consists just in this, that the principle of

action is free from all influence of contingent grounds, which alone

experience can furnish. We cannot too much or too often repeat our

warning against this lax and even mean habit of thought which seeks

for its principle amongst empirical motives and laws; for human reason

in its weariness is glad to rest on this pillow, and in a dream of

sweet illusions (in which, instead of Juno, it embraces a cloud) it

substitutes for morality a bastard patched up from limbs of various

derivation, which looks like anything one chooses to see in it, only

not like virtue to one who has once beheld her in her true form.*

*To behold virtue in her proper form is nothing else but to

contemplate morality stripped of all admixture of sensible things

and of every spurious ornament of reward or self-love. How much she

then eclipses everything else that appears charming to the affections,

every one may readily perceive with the least exertion of his

reason, if it be not wholly spoiled for abstraction.

The question then is this: "Is it a necessary law for all rational

beings that they should always judge of their actions by maxims of

which they can themselves will that they should serve as universal

laws?" If it is so, then it must be connected (altogether a priori)

with the very conception of the will of a rational being generally.

But in order to discover this connexion we must, however

reluctantly, take a step into metaphysic, although into a domain of it

which is distinct from speculative philosophy, namely, the

metaphysic of morals. In a practical philosophy, where it is not the

reasons of what happens that we have to ascertain, but the laws of

what ought to happen, even although it never does, i.e., objective

practical laws, there it is not necessary to inquire into the

reasons why anything pleases or displeases, how the pleasure of mere

sensation differs from taste, and whether the latter is distinct

from a general satisfaction of reason; on what the feeling of pleasure

or pain rests, and how from it desires and inclinations arise, and

from these again maxims by the co-operation of reason: for all this

belongs to an empirical psychology, which would constitute the

second part of physics, if we regard physics as the philosophy of

nature, so far as it is based on empirical laws. But here we are

concerned with objective practical laws and, consequently, with the

relation of the will to itself so far as it is determined by reason

alone, in which case whatever has reference to anything empirical is

necessarily excluded; since if reason of itself alone determines the

conduct (and it is the possibility of this that we are now

investigating), it must necessarily do so a priori.

The will is conceived as a faculty of determining oneself to

action in accordance with the conception of certain laws. And such a

faculty can be found only in rational beings. Now that which serves

the will as the objective ground of its self-determination is the end,

and, if this is assigned by reason alone, it must hold for all

rational beings. On the other hand, that which merely contains the

ground of possibility of the action of which the effect is the end,

this is called the means. The subjective ground of the desire is the

spring, the objective ground of the volition is the motive; hence

the distinction between subjective ends which rest on springs, and

objective ends which depend on motives valid for every rational being.

Practical principles are formal when they abstract from all subjective

ends; they are material when they assume these, and therefore

particular springs of action. The ends which a rational being proposes

to himself at pleasure as effects of his actions (material ends) are

all only relative, for it is only their relation to the particular

desires of the subject that gives them their worth, which therefore

cannot furnish principles universal and necessary for all rational

beings and for every volition, that is to say practical laws. Hence

all these relative ends can give rise only to hypothetical

imperatives.

Supposing, however, that there were something whose existence has in

itself an absolute worth, something which, being an end in itself,

could be a source of definite laws; then in this and this alone

would lie the source of a possible categorical imperative, i.e., a

practical law.

Now I say: man and generally any rational being exists as an end

in himself, not merely as a means to be arbitrarily used by this or

that will, but in all his actions, whether they concern himself or

other rational beings, must be always regarded at the same time as

an end. All objects of the inclinations have only a conditional worth,

for if the inclinations and the wants founded on them did not exist,

then their object would be without value. But the inclinations,

themselves being sources of want, are so far from having an absolute

worth for which they should be desired that on the contrary it must be

the universal wish of every rational being to be wholly free from

them. Thus the worth of any object which is to be acquired by our

action is always conditional. Beings whose existence depends not on

our will but on nature's, have nevertheless, if they are irrational

beings, only a relative value as means, and are therefore called

things; rational beings, on the contrary, are called persons,

because their very nature points them out as ends in themselves,

that is as something which must not be used merely as means, and so

far therefore restricts freedom of action (and is an object of

respect). These, therefore, are not merely subjective ends whose

existence has a worth for us as an effect of our action, but objective

ends, that is, things whose existence is an end in itself; an end

moreover for which no other can be substituted, which they should

subserve merely as means, for otherwise nothing whatever would possess

absolute worth; but if all worth were conditioned and therefore

contingent, then there would be no supreme practical principle of

reason whatever.

If then there is a supreme practical principle or, in respect of the

human will, a categorical imperative, it must be one which, being

drawn from the conception of that which is necessarily an end for

everyone because it is an end in itself, constitutes an objective

principle of will, and can therefore serve as a universal practical

law. The foundation of this principle is: rational nature exists as an

end in itself. Man necessarily conceives his own existence as being

so; so far then this is a subjective principle of human actions. But

every other rational being regards its existence similarly, just on

the same rational principle that holds for me:* so that it is at the

same time an objective principle, from which as a supreme practical

law all laws of the will must be capable of being deduced. Accordingly

the practical imperative will be as follows: So act as to treat

humanity, whether in thine own person or in that of any other, in

every case as an end withal, never as means only. We will now

inquire whether this can be practically carried out.

*This proposition is here stated as a postulate. The ground of it

will be found in the concluding section.

To abide by the previous examples:

Firstly, under the head of necessary duty to oneself: He who

contemplates suicide should ask himself whether his action can be

consistent with the idea of humanity as an end in itself. If he

destroys himself in order to escape from painful circumstances, he

uses a person merely as a mean to maintain a tolerable condition up to

the end of life. But a man is not a thing, that is to say, something

which can be used merely as means, but must in all his actions be

always considered as an end in himself. I cannot, therefore, dispose

in any way of a man in my own person so as to mutilate him, to

damage or kill him. (It belongs to ethics proper to define this

principle more precisely, so as to avoid all misunderstanding, e.

g., as to the amputation of the limbs in order to preserve myself,

as to exposing my life to danger with a view to preserve it, etc. This

question is therefore omitted here.)

Secondly, as regards necessary duties, or those of strict

obligation, towards others: He who is thinking of making a lying

promise to others will see at once that he would be using another

man merely as a mean, without the latter containing at the same time

the end in himself. For he whom I propose by such a promise to use for

my own purposes cannot possibly assent to my mode of acting towards

him and, therefore, cannot himself contain the end of this action.

This violation of the principle of humanity in other men is more

obvious if we take in examples of attacks on the freedom and

property of others. For then it is clear that he who transgresses

the rights of men intends to use the person of others merely as a

means, without considering that as rational beings they ought always

to be esteemed also as ends, that is, as beings who must be capable of

containing in themselves the end of the very same action.*

*Let it not be thought that the common "quod tibi non vis fieri,

etc." could serve here as the rule or principle. For it is only a

deduction from the former, though with several limitations; it

cannot be a universal law, for it does not contain the principle of

duties to oneself, nor of the duties of benevolence to others (for

many a one would gladly consent that others should not benefit him,

provided only that he might be excused from showing benevolence to

them), nor finally that of duties of strict obligation to one another,

for on this principle the criminal might argue against the judge who

punishes him, and so on.

Thirdly, as regards contingent (meritorious) duties to oneself: It

is not enough that the action does not violate humanity in our own

person as an end in itself, it must also harmonize with it. Now

there are in humanity capacities of greater perfection, which belong

to the end that nature has in view in regard to humanity in

ourselves as the subject: to neglect these might perhaps be consistent

with the maintenance of humanity as an end in itself, but not with the

advancement of this end.

Fourthly, as regards meritorious duties towards others: The

natural end which all men have is their own happiness. Now humanity

might indeed subsist, although no one should contribute anything to

the happiness of others, provided he did not intentionally withdraw

anything from it; but after all this would only harmonize negatively

not positively with humanity as an end in itself, if every one does

not also endeavour, as far as in him lies, to forward the ends of

others. For the ends of any subject which is an end in himself ought

as far as possible to be my ends also, if that conception is to have

its full effect with me.

This principle, that humanity and generally every rational nature is

an end in itself (which is the supreme limiting condition of every

man's freedom of action), is not borrowed from experience, firstly,

because it is universal, applying as it does to all rational beings

whatever, and experience is not capable of determining anything

about them; secondly, because it does not present humanity as an end

to men (subjectively), that is as an object which men do of themselves

actually adopt as an end; but as an objective end, which must as a law

constitute the supreme limiting condition of all our subjective

ends, let them be what we will; it must therefore spring from pure

reason. In fact the objective principle of all practical legislation

lies (according to the first principle) in the rule and its form of

universality which makes it capable of being a law (say, e. g., a

law of nature); but the subjective principle is in the end; now by the

second principle the subject of all ends is each rational being,

inasmuch as it is an end in itself. Hence follows the third

practical principle of the will, which is the ultimate condition of

its harmony with universal practical reason, viz.: the idea of the

will of every rational being as a universally legislative will.

On this principle all maxims are rejected which are inconsistent

with the will being itself universal legislator. Thus the will is

not subject simply to the law, but so subject that it must be regarded

as itself giving the law and, on this ground only, subject to the

law (of which it can regard itself as the author).

In the previous imperatives, namely, that based on the conception of

the conformity of actions to general laws, as in a physical system

of nature, and that based on the universal prerogative of rational

beings as ends in themselves- these imperatives, just because they

were conceived as categorical, excluded from any share in their

authority all admixture of any interest as a spring of action; they

were, however, only assumed to be categorical, because such an

assumption was necessary to explain the conception of duty. But we

could not prove independently that there are practical propositions

which command categorically, nor can it be proved in this section; one

thing, however, could be done, namely, to indicate in the imperative

itself, by some determinate expression, that in the case of volition

from duty all interest is renounced, which is the specific criterion

of categorical as distinguished from hypothetical imperatives. This is

done in the present (third) formula of the principle, namely, in the

idea of the will of every rational being as a universally

legislating will.

For although a will which is subject to laws may be attached to this

law by means of an interest, yet a will which is itself a supreme

lawgiver so far as it is such cannot possibly depend on any

interest, since a will so dependent would itself still need another

law restricting the interest of its self-love by the condition that it

should be valid as universal law.

Thus the principle that every human will is a will which in all

its maxims gives universal laws,* provided it be otherwise

justified, would be very well adapted to be the categorical

imperative, in this respect, namely, that just because of the idea

of universal legislation it is not based on interest, and therefore it

alone among all possible imperatives can be unconditional. Or still

better, converting the proposition, if there is a categorical

imperative (i.e., a law for the will of every rational being), it

can only command that everything be done from maxims of one's will

regarded as a will which could at the same time will that it should

itself give universal laws, for in that case only the practical

principle and the imperative which it obeys are unconditional, since

they cannot be based on any interest.