Groundwork of the Metaphysics of Morals | Study Guide

Immanuel Kant

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Groundwork of the Metaphysics of Morals | Summary




Kant sets out to identify and analyze what he calls "the supreme principle of morality." To this end he begins with an analysis of concepts with which people are familiar: good will and duty. These concepts reflect our ordinary ways of thinking about morality. A "person of good will" is one who attempts to do the right thing simply because it is right. If one were to ask that person why they acted as they did, they would respond that it was their responsibility to do so.

The ancient Greeks divided philosophical inquiry into physics, ethics, and logic. In logic, this inquiry proceeds formally, because the study concerns forms of thinking independently of any objects. All inquiry into physics proceeds according to laws of nature, of how things happen, while inquiry into ethics proceeds according to laws of freedom, of how human action ought to happen.

Philosophical inquiry can be further divided on the basis of experience or purely a priori principles. In other words, philosophy can be concerned with how experience occurs or how concepts occur independently of experience. Physics and ethics employ both, where the latter's empirical part is "practical anthropology," while its a priori part is "morals." Logic and metaphysics, meanwhile, focus on the latter. A "metaphysics of morals" is necessary to clarify and preserve the nature of moral obligation.

Section 1: Transition from Common Rational to Philosophic Moral Cognition

Kant's analysis of ordinary moral consciousness reveals that people believe they are bound by duty. Duty, in turn, Kant explains, "is the necessity of an action from respect for law." All inclination to the contrary, and even inclination toward duty is set aside, so that the only motivation is respect for law.

An analysis reveals that these concepts tell a person something important about the nature of morality. First, the good will is inherently good; it does not derive its value from the success or failure of its actions. Indeed, the attempt—the willing of the good—is what makes the will good. Second, the nature of duty is obligation. Duty has the power of necessity; one recognizes it as what one must do. As such, it has the force of law. Another way to put this is that the law applies categorically, that is, in all cases.

The binding power of the law reflects not only a universal command but also a universal command of reason. After all, given that the realm of experience is, by nature, contingent, no empirical fact can command as completely. Reason's command is an imperative: it is what must be done. When one does one's duty for its own sake, then one acts from respect for the moral law. One's motive is not, then, to see some outcome prevail or to indulge in one's own inclinations.

Section 2: Transition from Popular Moral Philosophy to Metaphysics of Morals

In more technical terms, the law is the "supreme moral principle" spelled out in the categorical imperative. Categorical imperatives are distinguished from hypothetical imperatives by their ends: a categorical imperative is a command applicable in all relevant instances, while a hypothetical imperative is a command applicable in particular instances where a desire to achieve some end obtains. Each motivates, but only those actions that accord with the categorical imperative motivate without condition and without regard to personal inclinations or selfish motives.

The categorical imperative is formulated variously according to universality, human dignity, autonomy, and a "kingdom of ends." One must be able to universalize one's personal rule for acting; one must treat oneself and others always as ends in themselves; one must act as if one legislated morality; and one must act as if one were a member of a legislative body in the ideal moral community.

Kant calls the moral law the categorical imperative: it is what one must always do (or not do). According to Kant, the first formulation of the categorical imperative is this: "Act only according to that maxim through which you can at the same time will that it become a universal law." With a small, yet significant addition, the categorical imperative is reformulated like this: "Act as if the maxim of your action were to become by your will a universal law of nature." The second formulation focuses on the dignity of persons: "So act that you use humanity, in your own person as well as in the person of any other, always at the same time as an end, never merely as a means." The third focuses on autonomy: "Every human will [is] a will universally legislating through all its maxims." The fourth is concerned with the moral community created by members acting morally: "A rational being must always consider itself as legislating in a kingdom of ends possible through freedom of the will."

Section 3: Transition from Metaphysics of Morals to the Critique of Pure Practical Reason

The analyses of Section 3 operate on the assumption that one has a will that is free to be motivated either by inclination or reason. It would be strange to claim that morality has the binding force of law if one were not free to do otherwise. Another way to put things is that deliberation and choice presuppose human freedom. So, even if the reality of freedom cannot be proven, it is at least not inconceivable. Moreover, it is plausible to think reason can motivate one to act, even if, again, such motivation cannot be proven.

Presupposed in the concepts of a good will, duty, and the categorical imperative is free will. While such freedom cannot be proven, it is possible that reason can motivate action. Moreover, deliberation and choice demonstrate the assumption of free will.

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