Kant: The Metaphysics of Morals

Preface

The critique of practical reason was to be followed by a system, the metaphysics of morals, which falls into metaphysical first principles of the doctrine of righta and metaphysical first principles of the doctrine of virtue. (This is the counterpart of the metaphysical first principles of natural science, already published.) The Introduction that follows presents and, to some degree, makes intuitive the form which the system will take in both these parts.

For the doctrine of right, the first part of the doctrine of morals, there is required a system derived from reason which could be called the metaphysics of right. But since the concept of right is a pure concept that still looks to practice (application to cases that come up in experience), a metaphysical system of right would also have to take account, in its divisions, of the empirical variety of such cases, in order to make its division complete (as is essential in constructing a system of reason). But what is empirical cannot be divided completely, and if this is attempted (at least to approximate to it), empirical concepts cannot be brought into the system as integral parts of it but can be used only as examples in remarks. So the only appropriate title for the first part of TheMetaphysics of Morals will be Metaphysical First Principles of the Doctrine of Right; for in the application of these principles to cases the system itself cannot be expected, but only approximation to it. Accordingly, it will be dealt with as in the (earlier) Metaphysical First Principles of Natural Science: namely, that right which belongs to the system outlined a priori will go into the text, while rights taken from particular cases of experience will be put into remarks, which will sometimes be extensive; for otherwise it would be hard to distinguish what is metaphysics here from what is empirical application of rights.

Philosophic treatises are often charged with being obscure, indeed deliberately unclear, in order to affect an illusion of deep insight. I cannot better anticipate or forestall this charge than by readily complying with a duty that Mr. Garve, a philosopher in the true sense of the word, lays down for all writers, but especially for philosophic writers. My only reservation is imposed by the nature of the science that is to be corrected and extended.