INTRODUCTION
Kant was born in 1724 Königsburg, Prussia, the son of a devout saddler. A very small, fragile man, he never left his home town, even when he reached the high post of Professor of Philosophy and was in demand throughout Europe. If there is one thing which characterizes him and his philosophy, it is precision. Such precision that his works are, to say the least, somewhat difficult reads. His daily life was no different, he never married, and, it is said, people would set their watches by when he left his house for his afternoon walk, at precisely 3.30. The street where he lived is now called "Philosopher's Walk"

Here in the Groundwork of the Metaphysic of Morals he aims to find the underlying principle which defines actions as good or bad, and ends up with the Categorical Imperative: that you must act such that you expect everyone to act the same way, and the Practical Imperative, that we must treat others only as ends, not merely as means. Remember that the next time you go to buy a bottle of beer- don't treat the cashier as a mere vehicle withal for swapping cash for goods- your duty is to make their life, for that moment, so much better and brighter.

THE VERY SQUASHED VERSION
The present treatise is the investigation and establishment of the supreme principle of morality.
1: FROM COMMON RATIONAL KNOWLEDGE OF MORALITY TO THE PHILOSOPHICAL
The only thing that can be completely good is a good will. Even good acts and good things can be put to bad use. Yet even if we fail utterly, our acting with good will yet still shines like a jewel, for it has value in itself alone. The basis of morals seems to be the rule that I am never to act otherwise than so that I could also will that my maxim should become a universal law. Can I be deceitful? No! Because if that became a universal law, if everyone was deceitful, it would pay me back in my own coin. Hence my maxim would destroy itself.
2: FROM POPULAR MORAL PHILOSOPHY TO THE METAPHYSIC OF MORALS
This rule is a Categorical Imperative. It clearly makes suicide, dishonesty, laziness and greed immoral. But we need to prove that this Categorical Imperative actually exists, even though there is nothing outside of us to base it on. Now, man necessarily conceives his own existence as being an end in himself, not merely as a means. Thus the practical imperative will be: 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, which equally forbids suicide, dishonesty, laziness and greed. Philosophers have failed in understanding morality by looking for something outside the will. Here, it is the will itself which makes its own law, making everyone both legislator and subject in a kingdom of ends. It is possible because of the autonomy of the will.
3: TRANSITION FROM THE METAPHYSIC OF MORALS TO THE CRITIQUE OF PURE PRACTICAL REASON
Freedom of the will follows necessarily from the idea of morality. But this is just 'analytic' analysis- the meaning proves itself, it is a circular argument. To prove it true we need a 'synthetic' proposition- one which is tested from outside of itself. However, man belongs mentally to two worlds, that of sense and that of the intelligible world, so a synthetic proposition based only on inate internal knowledge (a priori knowledge) is possible by comparing the one against the other. Practice confirms this, as even people who do bad things know that they are wrong. But we can never completely know why this should be so.

ABOUT THIS SQUASHED VERSION
This squashed version is based on the Thomas Kingsmill Abbott translation, with a few revisions from the 1997 version by Mary Gregor. Some of Kant's own footnotes have been inserted [in square brackets] into the body text. As the original is only about 31,000 words, and Kant is somewhat repetetive, this reduction has lost very little indeed of the original sense. The title has also been translated as Fundamental Principles of the Metaphysic of Morals.

GLOSSARY
Maxim: A subjective principle of action
Kingdom of ends: The union of different rational beings in a system by common laws.
A Priori Knowledge: That knowledge which is inate and necessary, needing no reference to things outside.
Analytic Propositions: Statements which prove themselves
Synthetic Propositions: Statements which are proved by things outside themselves.

KANT'S MORAL MAXIMS
The categorical imperative: Act only on that maxim whereby thou canst at the same time will that it should become a universal law.
The imperative of duty: Act as if the maxim of thy action were to become by thy will a universal law of nature.
The practical imperative: 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.

Groundwork of the Metaphysic of Morals
by Immanuel Kant, 1785
This edition edited by Glyn Hughes © 2002

PREFACE

Ancient Greek philosophy was divided into physics, ethics, and logic. The only improvement that can be made is to add the principle on which it is based.

All rational knowledge is either material or formal: the material considers objects, the formal is concerned with the form of the understanding and of the reason itself, with universal laws of thought in general. Formal philosophy is called logic. Material philosophy is divided into laws of nature, or natural philosophy, and laws of freedom, called ethics, or moral philosophy. That philosophy which delivers its doctrines from a priori principles alone we may call pure philosophy. When merely formal it is logic; if it is restricted to definite objects of the understanding it is metaphysic.

As my concern here is with moral philosophy, I limit my question to this: Is it not of the utmost necessity to construct a pure thing which is only empirical and which belongs to anthropology? That such a philosophy must be possible is evident from the common idea of duty and of the moral laws. The present treatise is nothing more than the investigation and establishment of the supreme principle of morality.

FIRST SECTION
TRANSITION FROM THE COMMON RATIONAL KNOWLEDGE OF MORALITY TO THE PHILOSOPHICAL

Nothing can possibly be conceived in the world, or even out of it, which can be called good without qualification, except a good will. Intelligence, wit, judgement, courage, resolution, perseverance, power, riches, honour, even health, are undoubtedly good; but these gifts may also become extremely bad and mischievous if the will which makes use of them is bad. It is the coolness of a villain which not only makes him far more dangerous, but also more abominable in our eyes.

A good will is good not because of what it performs or effects, but simply by virtue of the volition; that is, it is good in itself. Even if, through the disfavour of fortune, or the niggardly provision of a step-motherly nature, good will should yet achieve nothing, then, still, like a jewel, it would shine by its own light. Its usefulness or fruitfulness can neither add nor take away anything from this value.

There is, however, something so strange in this idea of the absolute value of the mere will, that a suspicion must arise that it may mere high-flown fancy. Therefore we will examine the idea.

In a being well adapted to survive, its conservation and welfare would be better served if its conduct were directed by instinct than by reason and will. Should such a creature then be favoured with reason, it would serve only for it to admire its own good fortune.

In fact, we find that the more a cultivated reason applies itself to enjoyment, the more does the man fail of true satisfaction. And from this circumstance there arises in many, if they are candid enough to confess it, a certain degree of misology, that is, hatred of reason.

Yet as reason is not competent to guide the will with certainty, it is nevertheless given to us as a practical faculty to influence the will. Thus the true vocation of reason must be to produce a will which is good.

We have then to develop the notion of a will which deserves to be highly esteemed for itself. In order to do this, we will take the notion of duty, which includes that of a good will.

I omit here all actions which are recognized as inconsistent with duty, or which men are impelled thereto by some other inclination. For example, it is a duty that a tradesman does not overcharge, but the action is done neither from duty nor from direct inclination, but merely with a selfish view.

On the other hand, it is a duty to preserve one's life. If adversity and hopeless sorrow have taken away the relish for life; if the unfortunate one wishes for death, and yet preserves his life without loving it- then his maxim [the subjective principle of volition] has a moral worth.

To be beneficent is a duty; and there are many minds so sympathetically constituted that they find a pleasure in spreading joy around them and take delight in the satisfaction of others so far as it is their own work. But I maintain that in such a case, however amiable it may be, has no true moral worth. It is in this manner, undoubtedly, that we are to understand those passages of Scripture in which we are commanded to love our neighbour.

The second proposition is: That an action done from duty derives its moral worth, not from the purpose which is to be attained by it, but from the maxim by which it is determined. In what, then, can their worth rest? It cannot rest anywhere but in the principle of the will without regard to the ends which can be attained by the action.

The third proposition, which is a consequence of the two preceding, I would express thus: Duty is the necessity of acting from respect for the law.

But what sort of law can that be, that this will may be called good absolutely and without qualification? There remains nothing but the universal conformity of its actions to law in general, which alone is to serve the will as a principle, ie., I am never to act otherwise than so that I could also will that my maxim should become a universal law. For example: May I, when in distress, make a promise with the intention not to keep it? The shortest way, and an unerring one, to answer this question, is to ask, "Should I be able to say to myself, "Every one may make a deceitful promise when he finds himself in a difficulty from which he cannot otherwise extricate himself?"" Then I presently become aware that while I can will the lie, I can by no means will that lying should be a universal law. For with such a law there would be no promises at all, since such would pay me back in my own coin. Hence my maxim, as soon as it should be made a universal law, would necessarily destroy itself.

Thus, then, without quitting the moral knowledge of common human reason, we have arrived at its principle. And although, no doubt, common men do not conceive it in such an abstract and universal form, yet they always have it really before their eyes and use it as the standard of their decision. Therefore, we do not need science and philosophy to know what we should do to be honest and good, yea, even wise and virtuous.

Innocence is indeed a glorious thing; only, on the other hand, it is very sad that it cannot well maintain itself and is easily seduced. On this account even wisdom- which otherwise consists more in conduct than in knowledge- yet has need of science, not in order to learn from it, but to secure admission and permanence for its precepts.

SECOND SECTION
TRANSITION FROM POPULAR MORAL PHILOSOPHY TO THE METAPHYSIC OF MORALS

If we have hitherto drawn our notion of duty from the common use of our practical reason, it is by no means to be inferred that it as a concept of experience.

In fact, it is absolutely impossible to make out by experience with complete certainty a single case in which the maxim of an action, however right in itself, rested simply on moral grounds and on the conception of duty. No matter how great the sacrifice, we cannot infer with certainty that it was not really done from some secret impulse of self-love. It is not with the actions which we see that we are concerned, but with those inward principles which we do not see.

I am willing to admit out of love of humanity that most of our actions are correct, but if we look closer at them we everywhere come upon the dear self. Without being an enemy of virtue, a cool observer may sometimes doubt whether true virtue is actually found anywhere in the world, whether there might never yet have been such a thing as a sincere friend.

When we add further that, unless we deny that the notion of morality has any truth or reference to any possible object, we must admit that its law must be valid, not merely for men but for all rational creatures generally, then it is clear that no experience could enable us to infer even the possibility of such apodeictic laws.

Nor could anything be more fatal to morality than that we should wish to derive it from examples. Even the Holy One of the Gospels must first be compared with our ideal of moral perfection before we can recognise Him as such; and so He says of Himself, "Why call ye Me (whom you see) good; none is good (the model of good) but God only (whom ye do not see)?" But whence have we the conception of God as the supreme good? Simply from the idea of moral perfection, which reason frames a priori and connects inseparably with the notion of a free will. Imitation finds no place at all in morality, and examples serve only for encouragement.

If then there is no genuine supreme principle of morality but what must rest simply on pure reason, independent of all experience, I think it is not necessary even to put the question whether it is good to exhibit these concepts in their generality (in abstracto) as they are established a priori along with the principles belonging to them, if our knowledge is to be distinguished from the vulgar and to be called philosophical.

In our times indeed this might perhaps be necessary; for if we collected votes whether pure rational knowledge separated from everything empirical, that is to say, metaphysic of morals, or popular practical philosophy is to be preferred, it is easy to guess which side would predominate.

This descending to popular notions is certainly very commendable, but it is quite absurd to try to be popular in the first inquiry. It also produces a disgusting medley of compiled observations and half-reasoned principles. Shallow pates enjoy this because it can be used for every-day chat, but the sagacious find in it only confusion, while philosophers, who see quite well through this delusion, are little listened to.

But in order to advance in natural steps in this study, we must follow and clearly describe the practical faculty of reason, from the general rules of its determination to the point where the notion of duty springs from it.

Everything in nature works according to laws. Rational beings alone have the faculty of acting according to the conception of laws, that is according to principles, ie., have a will. Since the deduction of actions from principles requires reason, the will is nothing but practical reason.

The conception of an objective principle, in so far as it is obligatory for a will, is called a command (of reason), and the formula of the command is called an imperative.

All imperatives are expressed by the word ought (or shall). They say that something would be good to do or to forbear, but they say it to a will which does not always do a thing because it is conceived to be good to do it.

Now all imperatives command either hypothetically or categorically. If the action is good only as a means to something else, then the imperative is hypothetical; if it is conceived as good in itself, then it is categorical.

Now arises the question, how are these imperatives possible? We shall therefore have to investigate a priori the possibility of a categorical imperative.

When I conceive a hypothetical imperative, in general I do not know beforehand what it will contain until I am given the condition. But when I conceive a categorical imperative, I know at once what it contains. For as the imperative contains besides the law only the necessity that the maxims [a subjective principle of action] shall conform to this law, while the law contains no conditions restricting it, there remains nothing but the general statement that the maxim of the action should conform to a universal law, and it is this conformity alone that the imperative properly represents as necessary.

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. 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), 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 to others, and into perfect and imperfect duties.

1. A man reduced to despair by a series of misfortunes feels wearied of life, and asks himself whether it would not be contrary to his duty to take his own life. We see at once that a system of nature in which it should be a law to destroy life would contradict itself and, therefore, could not exist; hence that maxim cannot possibly exist as a universal law of nature.

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 so. But supposing it to be a universal law that everyone when he thinks himself in a difficulty should be able to promise whatever he pleases, the promise itself would become impossible, 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 useful. But he prefers to indulge in pleasure rather than to take pains in improving his happy natural capacities. He sees that a system of nature could indeed subsist with such a universal law where men (like the South Sea islanders) devote their lives to idleness, amusement, and propagation of their species; but he cannot possibly will that this should be a universal law of nature. 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, thinks: "What concern is it of mine? But it is impossible to will that such a principle should have the universal validity of a law of nature, for many cases might occur in which one would have need of the love and sympathy of others.

We have 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 not yet, however, advanced so far as to prove a priori that there actually is such an imperative, and that following 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. Human reason may indeed supply us with a maxim, but not with a law.

Here then we see philosophy put in a precarious position, which is to be firmly fixed, even though it has nothing to support it in heaven or earth. Philosophy 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.

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.

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?" But in order to discover this connexion we must, however reluctantly, take a step into a domain of metaphysic, namely, the metaphysic of morals. Here we are concerned with the relation of the will to itself so far as it is determined by reason alone.

The will is conceived as a faculty of determining oneself to action in accordance with the conception of certain laws.

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.

Man necessarily conceives his own existence as being so. But every other rational being regards its existence similarly. 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.

To abide by the previous examples:

Firstly, 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, 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, damage or kill him. (It belongs to ethics proper to define this principle more precisely, so as to avoid all misunderstanding, eg., as to the amputation of limbs in order to preserve myself, as exposing my life to danger with a view to preserve it, etc.)

Secondly, as regards duties 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 means, without the latter containing at the same time the end in himself.

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.

Fourthly, as regards meritorious duties towards others: 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.

Thus 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).

Thus the principle that every human will is a will which in all its maxims gives universal laws, would be very well adapted to be the categorical imperative because the idea of universal legislation is not based on any particular interest, and therefore it alone can be unconditional.

Looking back now on all previous attempts to discover the principle of morality, we need not wonder why they all failed. It was not seen that the laws to which man is subject are only those of his own giving, though at the same time they are universal.

The conception of the will of every rational being as one which must consider itself as giving in all the maxims of its will universal laws leads to a very fruitful conception, namely that of a kingdom of ends.

By a kingdom I understand the union of different rational beings in a system by common laws. A rational being must always regard himself as giving laws either as member or as sovereign in a kingdom of ends which is rendered possible by the freedom of will.

Morality consists then in the reference of all action to the legislation which alone can render a kingdom of ends possible. This legislation must be capable of existing in every rational being and of emanating from his will, so that the principle of this will is never to act on any maxim which could not without contradiction be also a universal law and, accordingly, always so to act that the will could at the same time regard itself as giving in its maxims universal laws. If now the maxims of rational beings are not by their own nature coincident with this objective principle, then the necessity of acting on it is called practical necessitation, ie., duty. Duty does not apply to the sovereign in the kingdom of ends, but it does to every member of it and to all in the same degree.

In the kingdom of ends everything has either value or dignity. Whatever has a value can be replaced by something else which is equivalent; whatever, on the other hand, is above all value, and therefore admits of no equivalent, has a dignity.

Whatever has reference to the general inclinations and wants of mankind has a market price; whatever, without presupposing a want, corresponds to a certain taste, has a fancy price; but that which constitutes the condition under which alone anything can be an end in itself, this has not merely a relative worth, ie., value, but an intrinsic worth, that is, dignity.

Skill and diligence in labour have a market price; wit, lively imagination, and humour, have a fancy price; on the other hand, fidelity to promises, benevolence from principle (not from instinct), have an intrinsic worth.

What then is it which justifies virtue or the morally good disposition, in making such lofty claims? It is nothing less than the privilege it secures to the rational being of participating in the giving of universal laws, by which it qualifies him to be a member of a possible kingdom of ends. For it is the legislation itself which assigns the worth of everything, and must for that very reason possess dignity, that is an unconditional incomparable worth; and the word respect alone supplies a becoming expression for the esteem which a rational being must have for it. Autonomy then is the basis of the dignity of human and of every rational nature.

The three modes of presenting the principle of morality that have been adduced are at bottom only so many formulae of the very same law, and each of itself involves the other two. All maxims, in fact, have:

1. A form, consisting in universality.
2. A matter, namely, an end.
3. A complete characterization of all maxims by means of that formula, namely, that all maxims ought by their own legislation to harmonize with a possible kingdom of ends as with a kingdom of nature.

We can now end where we started at the beginning, namely, with the conception of a will unconditionally good. That will is absolutely good which cannot be evil- in other words, whose maxim, if made a universal law, could never contradict itself. This principle, then, is its supreme law: "Act always on such a maxim as thou canst at the same time will to be a universal law".

It follows incontestably that, to whatever laws any rational being may be subject, he being an end in himself must be able to regard himself as also legislating universally in respect of these same laws. Therefore every rational being must so act as if he were by his maxims in every case a legislating member in the universal kingdom of ends. Morality, then, is the relation of actions to the relation of actions will, that is, to the autonomy of potential universal legislation by its maxims. An action that is consistent with the autonomy of the will is permitted; one that does not agree therewith is forbidden. A will whose maxims necessarily coincide with the laws of autonomy is a holy will, good absolutely.

We have shown that neither fear nor inclination, but simply respect for the law, is the spring which can give actions a moral worth.

THE AUTONOMY OF THE WILL
AS THE SUPREME PRINCIPLE OF MORALITY

Autonomy of the will is that property of it by which it is a law to itself (independently of any property of the objects of volition). The principle of autonomy then is: "Always so to choose that the same volition shall comprehend the maxims of our choice as a universal law." We cannot prove that this practical rule is an imperative by a mere analysis of the conceptions which occur in it, since it is a synthetical proposition. But that the principle of autonomy is the sole principle of morals can be readily shown by mere analysis of the conceptions of morality. For we find that its principle must be a categorical imperative and that what this commands is neither more nor less than this very autonomy.

HETERONOMY OF THE WILL
AS THE SOURCE OF ALL SPURIOUS PRINCIPLES OF MORALITY

If the will seeks the law which is to determine it anywhere else than in the fitness of its maxims to be universal laws of its own creation, it goes out of itself and seeks this law in the character of any of its objects, there always results heteronomy. The will in that case does not give itself the law, but it is given by the object through its relation to the will. This relation, whether it rests on inclination or on conceptions of reason, only admits of hypothetical imperatives: "I ought to do something because I wish for something else." On the contrary, the moral, and therefore categorical, imperative says: "I ought to do so and so, even though I should not wish for anything else."

THIRD SECTION
TRANSITION FROM THE METAPHYSIC OF MORALS TO THE CRITIQUE OF PURE PRACTICAL REASON

THE CONCEPT OF FREEDOM IS THE KEY THAT EXPLAINS THE AUTONOMY OF THE WILL

The will is a kind of causality belonging to living beings in so far as they are rational, and freedom would be this property of such causality that it can be efficient, independently of foreign causes determining it. The preceding definition of freedom is negative and therefore unfruitful for the discovery of its essence, but it leads to a positive conception.

Since the conception of causality involves that of laws, what else then can freedom of the will be but autonomy, that is, the property of the will to be a law to itself? But the proposition: "The will is in every action a law to itself," only expresses the principle: "To act on no other maxim than that which can also have as an object itself as a universal law." Now this is precisely the formula of the categorical imperative and is the principle of morality, so that a free will and a will subject to moral laws are one and the same.

On the hypothesis, then, of freedom of the will, morality together with its principle follows from it by mere analysis of the conception. However, that is a synthetic proposition, and such synthetic propositions are only possible in this way: that the two cognitions are connected together by a third in which they are both to be found. We cannot now at once show what this third is of which we have an idea a priori; some further preparation is required.

FREEDOM MUST BE PRESUPPOSED AS A PROPERTY OF THE WILL OF ALL RATIONAL BEINGS

It is not enough to predicate freedom of our own will, if we have not grounds for predicating the same of all rational beings. For as morality serves as a law for us only because we are rational beings, it must also hold for all rational beings; and as it must be deduced simply from the property of freedom, it must be shown that freedom also is a property of all rational beings. Now I affirm that we must attribute to every rational being which has a will that it has also the idea of freedom and acts entirely under this idea. Now we cannot possibly conceive a reason consciously receiving a bias from any other quarter with respect to its judgements, for then the subject would ascribe the determination of its judgement not to its own reason. Consequently the will of such a being cannot be a will of its own except under the idea of freedom.

OF THE INTEREST ATTACHING TO THE IDEAS OF MORALITY

We have finally reduced the definite conception of morality to the idea of freedom. This latter, however, we could not prove to be actually a property of ourselves or of human nature; only we saw that it must be presupposed if we would conceive a being as rational and conscious of its causality in respect of its actions, ie., as endowed with a will.

It must be freely admitted that there is a sort of circle here from which it seems impossible to escape. In the order of efficient causes we assume ourselves free, in order that in the order of ends we may conceive ourselves as subject to moral laws: and we afterwards conceive ourselves as subject to these laws, because we have attributed to ourselves freedom of will.

One resource remains to us, namely, to inquire whether we do not occupy different points of view when by means of freedom we think ourselves as causes efficient a priori, and when we form our conception of ourselves from our actions as effects which we see before our eyes.

We can only attain to the knowledge of appearances, never to that of things in themselves. As soon as this distinction has once been made then it follows that we must admit and assume behind the appearance something else that is not an appearance, namely, the things in themselves. This must furnish a distinction, however crude, between a world of sense and the world of understanding.

Now man really finds in himself a faculty by which he distinguishes himself from everything else, even from himself as affected by objects, and that is reason. Hence he has two points of view from which he can regard himself, and recognise laws of the exercise of his faculties: first, so far as he belongs to the world of sense, he finds himself subject to laws of nature (heteronomy); secondly, as belonging to the intelligible world, under laws which, being independent of nature, have their foundation not in experience but in reason alone.

As a rational being, and consequently belonging to the intelligible world, man can never conceive the causality of his own will otherwise than on condition of the idea of freedom.

Now the suspicion is removed that there was a latent circle involved in our reasoning from freedom to autonomy. For now we see that, when we conceive ourselves as free, we transfer ourselves into the world of understanding as members of it and recognise the autonomy of the will with its consequence, morality; whereas, if we conceive ourselves as under obligation, we consider ourselves as belonging to the world of sense and at the same time to the world of understanding.

HOW IS A CATEGORICAL IMPERATIVE POSSIBLE?

Every rational being reckons himself, as intelligence, as belonging to the world of understanding, and also conscious of himself as a part of the world of sense in which his actions are displayed.

And thus what makes categorical imperatives possible is this, that the idea of freedom makes me a member of an intelligible world, in which all my actions would always conform to the autonomy of the will; but as I at the same time intuite myself as a member of the world of sense, they ought so to conform. It is this categorical "ought" which implies a synthetic a priori proposition, inasmuch as besides my will, as affected by sensible desires, there is added the further idea of the same will but as belonging to the world of the understanding. In this way synthetic a priori propositions become possible, on which all knowledge of physical nature rests.

The practical use of common human reason confirms this reasoning. There is no one, not even the most consummate villain, provided only that be is otherwise accustomed to the use of reason, who, when we set before him examples of honesty of purpose, of steadfastness in following good maxims, of sympathy and general benevolence, does not wish that he might also possess these qualities. Only on account of his inclinations and impulses he cannot attain this in himself, but at the same time he wishes to be free from such inclinations. What he morally "ought" is then what he necessarily "would," as a member of the world of the understanding, and is conceived by him as an "ought" only inasmuch as he likewise considers himself as a member of the world of sense.

OF THE EXTREME LIMITS OF ALL PRACTICAL PHILOSOPHY.

All men attribute to themselves freedom of will. Hence come all judgements upon actions as being such as ought to have been done, although they have not been done. However, this freedom is not a conception of experience, nor can it be so, since it still remains, even though experience shows the contrary.

There arises from this a dialectic of reason, since the freedom attributed to the will appears to contradict the necessity of nature. Philosophy must then assume that no real contradiction will be found between freedom and physical necessity.

Nevertheless, even though we should never be able to comprehend how freedom is possible, we must at least remove this apparent contradiction in a convincing manner.

It would be impossible to escape this contradiction if the thinking subject seems to itself free even when subject to the law of nature.

But freedom is a mere idea, the objective reality of which can in no wise be shown according to laws of nature. Now where determination according to laws of nature ceases, there all explanation ceases also, and nothing remains but defence, ie., the removal of the objections of those who pretend to have seen deeper into the nature of things, and thereupon boldly declare freedom impossible.

The subjective impossibility of explaining the freedom of the will is identical with the impossibility of discovering and explaining an interest which man can take in the moral law. Nevertheless he does actually take an interest in it, because it is valid for us as men, inasmuch as it had its source in our will as intelligences, in other words, in our proper self.

The question then, "How a categorical imperative is possible," can be answered to this extent, that we can assign the only hypothesis on which it is possible, namely, the idea of freedom; but how this hypothesis itself is possible can never be discerned by any human reason. To explain how pure reason can be of itself practical is beyond the power of human reason, and all the labour and pains of seeking an explanation of it are lost.

Here now is the extreme limit of all moral inquiry, and it is of great importance to determine it in order that reason may not impotently flap its wings without being able to move in the empty space of transcendent concepts. For the rest, the idea of a pure world of understanding to which we as rational beings belong (while also being members of the sensible world), remains a useful and legitimate idea to produce in us a lively interest in the moral law.

CONCLUDING REMARK

It is no fault in our deduction of the supreme principle of morality, but an objection to human reason in general, that it cannot enable us to conceive the absolute necessity of an unconditional practical law (such as the categorical imperative). And thus while we do not comprehend the practical unconditional necessity of the moral imperative, we yet comprehend its incomprehensibility, and this is all that can be fairly demanded of a philosophy which strives to carry its principles up to the very limit of human reason.

Immanuel Kant
1724-1804
Kant's grave in Kaliningrad Cemetery, Kaliningrad, Russia