Front Page Titles (by Subject) III.: The Division of a Metaphysic of Morals. - The Philosophy of Law: An Exposition of the Fundamental Principles of Jurisprudence as the Science of Right
Return to Title Page for The Philosophy of Law: An Exposition of the Fundamental Principles of Jurisprudence as the Science of Right
The Online Library of Liberty
A project of Liberty Fund, Inc.
Search this Title:
III.: The Division of a Metaphysic of Morals. - Immanuel Kant, The Philosophy of Law: An Exposition of the Fundamental Principles of Jurisprudence as the Science of Right 
The Philosophy of Law: An Exposition of the Fundamental Principles of Jurisprudence as the Science of Right, by Immanuel Kant, trans. W. Hastie (Edinburgh: Clark, 1887).
About Liberty Fund:
Liberty Fund, Inc. is a private, educational foundation established to encourage the study of the ideal of a society of free and responsible individuals.
The text is in the public domain.
Fair use statement:
This material is put online to further the educational goals of Liberty Fund, Inc. Unless otherwise stated in the Copyright Information section above, this material may be used freely for educational and academic purposes. It may not be used in any way for profit.
The Division of a Metaphysic of Morals.
Two Elements involved in all Legislation.—All Legislation, whether relating to internal or external action, and whether prescribed à priori by mere Reason or laid down by the Will of another, involves two Elements:—1st, a Law which represents the action that ought to happen as necessary objectively, thus making the action a Duty; 2nd, a Motive which connects the principle determining the Will to this action with the Mental representation of the Law subjectively, so that the Law makes Duty the motive of the Action. By the first element, the action is represented as a Duty, in accordance with the mere theoretical knowledge of the possibility of determining the activity of the Will by practical Rules. By the second element, the Obligation so to act, is connected in the Subject with a determining Principle of the Will as such.
Division of Duties into Juridical and Ethical. — All Legislation, therefore, may be differentiated by reference to its Motive-principle.1 The Legislation which makes an Action a Duty, and this Duty at the same time a Motive, is ethical. That Legislation which does not include the Motive-principle in the Law, and consequently admits another Motive than the idea of Duty itself, is juridical. In respect of the latter, it is evident that the motives distinct from the idea of Duty, to which it may refer, must be drawn from the subjective (pathological) influences of Inclination and of Aversion, determining the voluntary activity, and especially from the latter: because it is a Legislation which has to be compulsory, and not merely a mode of attracting or persuading. The agreement or non-agreement of an action with the Law, without reference to its Motive, is its Legality; and that character of the action in which the idea of Duty arising from the Law, at the same time forms the Motive of the Action, is its Morality.
Duties specially in accord with a Juridical Legislation, can only be external Duties. For this mode of Legislation does not require that the idea of the Duty, which is internal, shall be of itself the determining Principle of the act of Will; and as it requires a motive suitable to the nature of its laws, it can only connect what is external with the Law. Ethical Legislation, on the other hand, makes internal actions also Duties, but not to the exclusion of the external, for it embraces everything which is of the nature of Duty. And just because ethical Legislation includes within its Law the internal motive of the action as contained in the idea of Duty, it involves a characteristic which cannot at all enter into the Legislation that is external. Hence, Ethical Legislation cannot as such be external, not even when proceeding from a Divine Will, although it may receive Duties which rest on an external Legislation as Duties, into the position of motives, within its own Legislation.
Jurisprudence and Ethics distinguished.—From what has been said, it is evident that all Duties, merely because they are duties, belong to Ethics; and yet the Legislation upon which they are founded is not on that account in all cases contained in Ethics. On the contrary, the Law of many of them lies outside of Ethics. Thus Ethics commands that I must fulfil a promise entered into by Contract, although the other party might not be able to compel me to do so. It adopts the Law ‘pacta sunt servanda,’ and the Duty corresponding to it, from Jurisprudence or the Science of Right, by which they are established. It is not in Ethics, therefore, but in Jurisprudence, that the principle of the Legislation lies, that ‘promises made and accepted must be kept.’ Accordingly, Ethics specially teaches that if the Motive-principle of external compulsion which Juridical Legislation connects with a Duty is even let go, the idea of Duty alone is sufficient of itself as a Motive. For were it not so, and were the Legislation itself not juridical, and consequently the Duty arising from it not specially a Duty of Right as distinguished from a Duty of Virtue, then Fidelity in the performance of acts, to which the individual may be bound by the terms of a Contract, would have to be classified with acts of Benevolence and the Obligation that underlies them, which cannot be correct. To keep one’s promise is not properly a Duty of Virtue, but a Duty of Right; and the performance of it can be enforced by external Compulsion. But to keep one’s promise, even when no Compulsion can be applied to enforce it, is, at the same time, a virtuous action, and a proof of Virtue. Jurisprudence as the Science of Right, and Ethics as the Science of Virtue, are therefore distinguished not so much by their different Duties, as rather by the difference of the Legislation which connects the one or the other kind of motive with their Laws.
Ethical Legislation is that which cannot be external, although the Duties it prescribes may be external as well as internal. Juridical Legislation is that which may also be external. Thus it is an external duty to keep a promise entered into by Contract; but the injunction to do this merely because it is a duty, without regard to any other motive, belongs exclusively to the internal Legislation. It does not belong thus to the ethical sphere as being a particular kind of duty or a particular mode of action to which we are bound,—for it is an external duty in Ethics as well as in Jurisprudence, — but it is because the Legislation in the case referred to is internal, and cannot have an external Lawgiver, that the Obligation is reckoned as belonging to Ethics. For the same reason, the Duties of Benevolence, although they are external Duties as Obligations to external actions, are, in like manner, reckoned as belonging to Ethics, because they can only be enjoined by Legislation that is internal.—Ethics has no doubt its own peculiar Duties,—such as those towards oneself,—but it has also Duties in common with Jurisprudence, only not under the same mode of Obligation. In short, the peculiarity of Ethical Legislation is to enjoin the performance of certain actions merely because they are Duties, and to make the Principle of Duty itself—whatever be its source or occasion—the sole sufficing motive of the activity of the Will. Thus, then, there are many ethical Duties that are directly such; and the inner Legislation also makes the others—all and each of them—indirectly Ethical.
[1 ]This ground of Division will apply, although the action which it makes a duty may coincide with another action, that may be otherwise looked at from another point of view. For instance, Actions may in all cases be classified as external.