The Kantian Ethics: Metaphysics of Morals, The Critique of Practical Reason & Perpetual Peace. Immanuel Kant
from the observance of her commands than from their transgression, especially if Prudence guides the conduct, yet the authority of her precepts as Commands does not rest on such considerations. They are used by Reason only as Counsels, and by way of a counterpoise against seductions to an opposite course, when adjusting beforehand the equilibrium of a partial balance in the sphere of Practical Judgment, in order thereby to secure the decision of this Judgment, according to the due weight of the a priori Principles of a pure Practical Reason.
The Necessity of a Metaphysic of Morals. —'Metaphysics' designates any System of Knowledge a priori that consists of pure Conceptions. Accordingly a Practical Philosophy not having Nature, but the Freedom of the Will for its object, will presuppose and require a Metaphysic of Morals. It is even a Duty to have such a Metaphysic; and every man does, indeed, possess it in himself, although commonly but in an obscure way. For how could any one believe that he has a source of universal Law in himself, without Principles a priori? And just as in a Metaphysic of Nature there must be principles regulating the application of the universal supreme Principles of Nature to objects of Experience, so there cannot but be such principles in the Metaphysic of Morals; and we will often have to deal objectively with the particular nature of man as known only by Experience, in order to show in it the consequences of these universal Moral Principles. But this mode of dealing with these Principles in their particular applications will in no way detract from their rational purity, or throw doubt on their a priori origin. In other words, this amounts to saying that a Metaphysic of Morals cannot be founded on Anthropology as the Empirical Science of Man, but may be applied to it.
Moral Anthropology.—The counterpart of a Metaphysic of Morals, and the other member of the Division of Practical Philosophy, would be a Moral Anthropology, as the Empirical Science of the Moral Nature of Man. This Science would contain only the subjective conditions that hinder or favour the realization in practice of the universal moral Laws in human Nature, with the means of propagating, spreading, and strengthening the Moral Principles,—as by the Education of the young and the instruction of the people,—and all other such doctrines and precepts founded upon experience and indispensable in themselves, although they must neither precede the metaphysical investigation of the Principles of Reason, nor be mixed up with it. For, by doing so, there would be a great danger of laying down false, or at least very flexible Moral Laws, which would hold forth as unattainable what is not attained only because the Law has not been comprehended and presented in its purity, in which also its strength consists. Or, otherwise, spurious and mixed motives might be adopted instead of what is dutiful and good in itself; and these would furnish no certain Moral Principles either for the guidance of the Judgment or for the discipline of the heart in the practice of Duty. It is only by Pure Reason, therefore, that Duty can and must be prescribed.
Practical Philosophy in relation to Art.—The higher Division of Philosophy, under which the Division just mentioned stands, is into Theoretical Philosophy and Practical Philosophy. Practical Philosophy is just Moral Philosophy in its widest sense, as has been explained elsewhere.[3] All that is practicable and possible, according to Natural Laws, is the special subject of the activity of Art, and its precepts and rules entirely depend on the Theory of Nature. It is only what is practicable according to Laws of Freedom that can have Principles independent of Theory, for there is no Theory in relation to what passes beyond the determinations of Nature. Philosophy therefore cannot embrace under its practical Division a technical Theory, but only a morally practical Doctrine. But if the dexterity of the Will in acting according to Laws of Freedom, in contradistinction to Nature, were to be also called an Art, it would necessarily indicate an Art which would make a System of Freedom possible like the System of Nature. This would truly be a Divine Art, if we were in a position by means of it to realize completely what Reason prescribes to us, and to put the Idea into practice.
III.
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 a 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.[4] 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