Kant, Immanuel (1724–1804)

10. Duties of right and duties of virtue

In the Groundwork, Kant’s principle of morality gives rise to a fourfold classification of duties, resulting from the intersection of two divisions: between duties to oneself and to others, and between perfect and imperfect duties. Perfect duties are proscriptions of specific kinds of actions, and violating them is morally blameworthy; imperfect duties are prescriptions of general ends, and fulfilling them by means of performing appropriate particular actions is praiseworthy. The four classes of duty are thus: perfect duties to oneself, such as the prohibition of suicide; perfect duties to others, such as the prohibition of deceitful promises; imperfect duties to oneself, such as the prescription to cultivate one’s talents; and imperfect duties to others, such as the prescription of benevolence (4: 422–3, 429–30). It is straightforward what a perfect duty prohibits one from doing; it requires judgment to determine when and how the general ends prescribed by imperfect duties should be realized through particular actions.

In the later Metaphysics of Morals, Kant works out a detailed budget of duties that is generally based on this scheme, but with one key distinction: duties of justice (Recht) are those of the above duties that can appropriately be enforced by means of the public, juridical use ofcoercion, and the remainder are duties of virtue, which are fit subjects for moral assessment but not coercion (6: 213, 219). Since freedom is Kant’s chief value, coercion is permitted only where it is both necessary to preserve freedom and possible for it to do so. This means that only a small subset of our duties, namely some but not all of our perfect duties to others, are duties of justice, thus proper subjects for public legislation; the majority of our moral duties are duties of virtue which are not appropriate subjects for coercive legal enforcement.

Kant’s treatment of the duties of virtue is less complicated than that of the duties of justice, and will be considered first. Kant does not explicitly characterize these as duties to preserve and promote the freedom of oneself and others, as he does in the Groundwork, but instead characterizes them as duties to promote one’s own perfection and the happiness of others: while one can directly perfect one’s own freedom, one can avoid injuring but not directly perfect the freedom of another. On close inspection, however, Kant’s duties of virtue require precisely that one perfect both the internal and external conditions for the exercise of one’s own freedom and at least the external conditions for the exercise of the freedom of others. Thus, ethical duties to oneself include the prohibition of injury to the physical and mental bases of one’s free agency, as by suicide or drunkenness, and the prescription of efforts to improve both the physical and mental conditions for the exercise of one’s freedom, as by the cultivation of talents and of one’s spiritual and moral faculties themselves; and ethical duties to others include both the prohibition of injuries to the dignity of others as free agents, for example by insulting or ridiculing them (‘duties of respect’), and the prescription of efforts to improve the conditions for others’ exercise of their own freedom, as by beneficience and sympathy (‘duties of love’).

Kant’s foundation of his political philosophy on the duties of justice is more complicated. From the ultimate value of freedom, Kant derives the universal principle of justice, that an action is right only if ‘on its maxim the freedom of choice of each can coexist with everyone’s freedom in accordance with a universal law’ (6: 230). Kant then argues that coercion is justified when it can prevent a hindrance to freedom, since a hindrance to a hindrance to freedom is itself a means to freedom (6: 231). This is too simple, since coercion might only compound the injury to freedom. Kant needs to add that coercive enforcement of the law is not itself a hindrance to freedom, since the threat of juridical sanction does not deprive a would-be criminal of freedom in the way that his crime would deprive its victim of freedom: the criminal exercises the choice to risk sanction, but deprives his victim of a like freedom of choice.

Kant goes on to argue that the only proper aim of coercive juridical legislation is the prevention of injury to the person and property of others; this is ‘Private Law’, while ‘Public Law’ concerns the proper form of the state, whose function is the enforcement of private law. Kant takes the prevention of injury to persons to be an obvious requirement of duty, needing no special discussion, but the right to property receives extended discussion.

Kant recognizes three classes of property: property in things, property in contracts, and contract-like property in other persons, such as marital rights. His discussion of property in things is the most important for his political theory. The gist of Kant’s account is that it would be irrational to deprive ourselves of the right to place physical objects, above all land, at our own long-term disposal, since we are rational agents who may need to use such things to realize our freely chosen ends, while the things themselves are not free agents and have no rights. But since the earth is initially undivided, specific property rights are not innate but must be acquired. Since the claim to any particular thing would limit the freedom of others who might also be able to use it, however, property rights cannot be claimed unilaterally, at least if morality’s insistence upon universal acceptability is to be respected, but can only be claimed with the multilateral consent of those others, which they can reasonably give only if they too are accorded similar rights necessary for the successful exercise of their own agency (6: 255–6). For Kant, the right to property is thus not a natural right of isolated individuals, but a social creation depending upon mutual acceptability of claims. The state, finally, exists primarily to make claims to property rights both determinate and secure, and anyone claiming property rights thus has both the right and the obligation to join in a state with others (6: 256–7, 306–8). Since property exists only by mutual consent, and the state exists to secure that consent, the state necessarily has the power to permit only those distributions of property rights sufficiently equitable to gain general consent.

Both claims to property and expressions of philosophical and religious opinions, for example, are expressions of human autonomy. But while one person’s property claims may directly limit the freedom of others, and are therefore subject to public regulation, his beliefs do not, and thus do not require the consent of any other. The state therefore has no right to intervene in these matters. This fundamental difference between the state’s proper concern with property and its improper concern with personal belief defines Kant’s liberalism. It is only implicit in the Metaphysics of Morals, but becomes explicit in more purely political writings.