Section One: From Common Moral Knowledge to Philosophical Knowledge

Preface

Ancient Greek philosophy was divided into three sciences: physics, ethics and logic. This division is perfectly suited to the nature of the thing. All rational knowledge is either material, concerned with some object, or formal, concerned only with the form of the understanding and of reason itself. Formal philosophy is called logic; material philosophy, concerned with determinate objects and the laws to which they are subject, is again twofold: the laws are either laws of nature or laws of freedom. The science of the first is physics; of the second, ethics.

Everyone must admit that a law, if it is to hold morally — that is, as a ground of obligation — must carry with it absolute necessity; that the command "Thou shalt not lie" does not hold only for human beings, as if other rational beings did not have to heed it; and so with all other genuine moral laws. The ground of obligation here must therefore not be sought in the nature of the human being, or in the circumstances of the world in which he is placed, but a priori, solely in concepts of pure reason.

The present groundwork is nothing more than the search for and establishment of the supreme principle of morality.

The Good Will

It is impossible to think of anything at all in the world, or indeed even beyond it, that could be considered good without limitation except a good will.

Understanding, wit, judgement and whatever else the talents of the mind may be called; or courage, resolution and perseverance in one's projects, as qualities of temperament — are undoubtedly in many respects good and desirable. But they can also become extremely evil and harmful, if the will which is to make use of these gifts of nature, and whose particular constitution is therefore called character, is not good. It is the same with the gifts of fortune. Power, riches, honour, even health, and that complete well-being and contentment with one's condition which is called happiness, produce boldness and often arrogance as well, unless there is a good will to correct their influence on the mind.

The coolness of a villain makes him not only far more dangerous, but also immediately more abominable in our eyes than he would have been held to be without it.

A good will is good not because of what it effects or accomplishes, not because of its fitness to attain some proposed end, but only because of its willing — that is, it is good in itself. Even if, by a special disfavour of fortune, or by the niggardly provision of a stepmotherly nature, this will should wholly lack the capacity to carry out its purpose; if with its greatest efforts it should still accomplish nothing, and only the good will were left (not, to be sure, as a mere wish, but as the summoning of all means insofar as they are in our control): then, like a jewel, it would still shine by itself, as something that has its full worth in itself. Usefulness or fruitlessness can neither add anything to this worth nor take anything away from it.

The image of the good will "shining like a jewel" is among the most famous in Kant.

Why has nature given us reason? If the purpose of nature for a being with reason and will were its preservation, its welfare — in a word, its happiness — then nature would have hit upon a very bad arrangement in choosing the reason of the creature to carry out this purpose. For instinct would have served it far better. Reason's true vocation must therefore be to produce a will good not as a means to something else, but good in itself.

Duty

To develop the concept of a will good in itself, we take up the concept of duty, which contains that of a good will, though under certain subjective limitations and hindrances — which, far from hiding it, rather bring it out by contrast and make it shine all the more brightly.

It is in conformity with duty that a shopkeeper should not overcharge an inexperienced customer; and where there is much trade, a prudent merchant does not do so, but keeps a fixed general price for everyone, so that a child may buy from him as well as anyone else. People are thus served honestly. But this is not nearly enough to make us believe that the merchant acted so from duty and principles of honesty; his advantage required it.

To preserve one's life is a duty; and besides, everyone has an immediate inclination to do so. But for that reason the often anxious care that most people take for it has no inner worth. But if adversities and hopeless grief have quite taken away the taste for life; if an unfortunate man, strong of soul, more indignant about his fate than despondent or dejected, wishes for death, and yet preserves his life without loving it — not from inclination or fear, but from duty — then his maxim has moral content.

Kant's example is of a man who, in despair, nevertheless chooses to live; the passage is about duty, and gives no detail.

To be beneficent where one can is a duty; and besides, there are many souls so sympathetically attuned that, without any other motive of vanity or self-interest, they find an inner satisfaction in spreading joy around them. But I assert that in such a case an action of this kind, however dutiful and amiable it may be, has nevertheless no true moral worth. Suppose then that the mind of this friend of humanity were clouded by his own grief, which extinguished all sympathy with the fate of others; that he still had the means to help others in need, but their need did not touch him, because he is sufficiently busy with his own; and that now, when no inclination any longer stimulates him to it, he tears himself out of this deadly insensibility, and performs the action without any inclination, simply from duty — then for the first time his action has its genuine moral worth.

This passage has often been taken to mean that Kant thought acts done with feeling worthless. His point is narrower: that only the motive of duty shows moral worth unmistakably.

It is undoubtedly in this way that we are to understand the passages of Scripture in which we are commanded to love our neighbour, even our enemy. For love as an inclination cannot be commanded; but beneficence from duty, even when no inclination impels us to it — indeed, when natural and unconquerable aversion opposes it — is practical, and not pathological, love.

The second proposition is this: an action from duty has its moral worth not in the purpose to be attained by it, but in the maxim according to which it is decided upon.

The third proposition, as a consequence of the two preceding: duty is the necessity of an action from respect for the law.

The First Formula

But what kind of law can that be, the representation of which must determine the will, even without regard to the effect expected from it, in order that the will may be called good absolutely and without qualification? Since I have deprived the will of every impulse that could arise for it from obeying any particular law, nothing is left but the conformity of actions as such with universal law, which alone is to serve the will as its principle. That is: I ought never to act except in such a way that I could also will that my maxim should become a universal law.

Take this question: may I, when I am in distress, make a promise with the intention of not keeping it? To answer it in the shortest and yet infallible way, I ask myself: would I indeed be content that my maxim (to get out of a difficulty by a false promise) should hold as a universal law, for myself as well as for others? And I soon become aware that I could indeed will the lie, but by no means a universal law to lie. For by such a law there would properly be no promises at all, since it would be in vain to profess my will with regard to my future actions to others who would not believe this profession. So my maxim, as soon as it were made a universal law, would destroy itself.

I do not need any far-reaching acuteness to see what I have to do in order that my will be morally good. Inexperienced in regard to the course of the world, incapable of being prepared for whatever might come to pass in it, I ask myself only: can you also will that your maxim should become a universal law?

Common human reason, with this compass in hand, knows very well how to distinguish in every case that comes up what is good, what is evil, what is in conformity with duty or contrary to it. There is no need of science and philosophy to know what one has to do in order to be honest and good, and even wise and virtuous.

Innocence is a splendid thing; but it is very bad that it cannot preserve itself, and is easily led astray. Against the precepts of duty, man feels a powerful counterweight in his needs and inclinations; and so arises a natural dialectic — a propensity to quibble with the strict laws of duty. This is what drives common reason into the field of practical philosophy.