Transition from popular moral philosophy to the metaphysics of morals

If so far we have drawn our concept of duty from the common use of our practical reason, it is by no means to be inferred from this that we have treated it as an experiential concept. Rather, if we attend to our experience of the behaviour of human beings we meet frequent and, as we ourselves concede, just complaints that no reliable example can be cited of the disposition to act from pure duty; that, though much may be done that conforms with what duty commands, still it is always doubtful whether it is actually done from duty and thus has a moral worth. That is why there have been philosophers in every age who have absolutely denied the actuality of this disposition in human actions, and attributed everything to a more or less refined self-love, without however calling into doubt the correctness of the concept of morality because of this; rather, with intimate regret they made mention of the frailty and impurity of a human nature that is indeed noble enough to take an idea so worthy of respect as its prescription, but at the same time too weak to follow it, and that uses reason, which should serve it for legislation, only to take care of the interest of inclinations, whether singly or, at most, in their greatest compatibility with one another.

Translators of philosophical texts inevitably obscure the author's arguments. The least they can do to lift the ‘veil of translation’ is to present text and translation side by side. In this book, this is done for Kant's Grundlegung zur Metaphysik der Sitten for the first time in its English-language history. I hope that it will encourage English speakers to study the German original, and thus bridge the divide between those working on Kant's ethics in both linguistic and philosophical traditions.

As the purpose of this volume is the clear and transparent presentation of the Groundwork itself, supplementary material has been kept to a minimum. This introduction explains the principles of the edition and the translation, particularly the constitution of the German text. In addition, the book contains a full bilingual index (which can also serve as an English–German glossary), a brief critical apparatus and editorial notes that explain matters of linguistic detail. These notes rarely stray into philosophically controversial territory. They do not serve the purpose of a guide to Kant's ethical thought. Interpretative and philosophical issues are discussed in my Kant's ‘Groundwork of the Metaphysics of Morals’: A Commentary (Cambridge University Press, 2007), which in many ways complements this edition as its sister volume.

The German text on the left-hand side of the double page is taken from the second original edition of the Groundwork, published in Riga by Johann Friedrich Hartknoch in 1786.

Transition from common to philosophical moral rational cognition

It is impossible to think of anything at all in the world, or indeed even beyond it, that could be taken to be good without limitation, except a good will. Understanding, wit, judgement and whatever else the talents of the mind may be called, or confidence, resolve and persistency of intent, as qualities of temperament, are no doubt in many respects good and desirable; but they can also be extremely evil and harmful if the will that is to make use of these gifts of nature, and whose distinctive constitution is therefore called character, is not good. It is just the same with gifts of fortune. Power, riches, honour, even health, and the entire well-being and contentment with one's condition, under the name of happiness, inspire confidence and thereby quite often overconfidence as well, unless a good will is present to correct and make generally purposive their influence on the mind, and with it also the whole principle for acting; not to mention that a rational impartial spectator can nevermore take any delight in the sight of the uninterrupted prosperity of a being adorned with no feature of a pure and good will, and that a good will thus appears to constitute the indispensable condition even of the worthiness to be happy.

Ancient Greek philosophy was divided into three sciences: physics, ethics and logic. This division is perfectly suitable to the nature of the matter, and there is no need to amend it, except perhaps just to add its principle, partly so as to assure oneself in this way of its completeness, partly to be able to determine correctly the necessary subdivisions.

All rational cognition is either material and considers some object, or formal and occupied merely with the form of the understanding and of reason itself, and with the universal rules of thinking as such, regardless of differences among its objects. Formal philosophy is called logic, whereas material philosophy, which has to do with determinate objects and the laws to which they are subject, is once again twofold. For these laws are either laws of nature, or of freedom. The science of the first is called physics, that of the other is ethics; the former is also called doctrine of nature, the latter doctrine of morals.

Logic can have no empirical part, i.e. one in which the universal and necessary laws of thinking would rest on grounds taken from experience; for in that case it would not be logic, i.e. a canon for the understanding, or for reason, that holds and must be demonstrated in all thinking.

Transition from the metaphysics of morals to the critique of pure practical reason

The concept of freedom is the key to the explanation of the autonomy of the will

A will is a kind of causality of living beings in so far as they are rational, and freedom would be that property of such a causality, as it can be efficient independently of alien causes determining it; just as natural necessity is the property of the causality of all nonrational beings to be determined to activity by the influence of alien causes.

The explication of freedom stated above is negative and therefore unfruitful for gaining insight into its essence; but there flows from it a positive concept of freedom, which is so much the richer and more fruitful. Since the concept of causality carries with it that of laws according to which, by something that we call a cause, something else, namely the consequence, must be posited: freedom, though it is not a property of the will according to natural laws, is not lawless because of that at all, but must rather be a causality according to immutable laws, but of a special kind; for otherwise a free will would be an absurdity. Natural necessity was a heteronomy of efficient causes; for every effect was possible only according to the law that something else determines the efficient cause to causality; what else, then, can freedom of the will be, but autonomy, i.e. the property of the will of being a law to itself?