How would Aristotle’s happiness as functioning well? balance Mill’s notion of utilitarianism as the greatest good for the greatest number??? And how would this balance reflect upon

Stanford Encyclopedia of Philosophy Kant’s Moral Philosophy First published Mon Feb 23, 2004; substantive revision Thu Jul 7, 2016

Immanuel Kant (1724–1804) argued that the supreme principle of morality is a standard of rationality that he dubbed the “Categorical Imperative” (CI). Kant characterized the CI as an objective, rationally necessary and unconditional principle that we must always follow despite any natural desires or inclinations we may have to the contrary. All specific moral requirements, according to Kant, are justified by this principle, which means that all immoral actions are irrational because they violate the CI. Other philosophers, such as Hobbes, Locke and Aquinas, had also argued that moral requirements are based on standards of rationality. However, these standards were either instrumental principles of rationality for satisfying one’s desires, as in Hobbes, or external rational principles that are discoverable by reason, as in Locke and Aquinas. Kant agreed with many of his predecessors that an analysis of practical reason reveals the requirement that rational agents must conform to instrumental principles. Yet he also argued that conformity to the CI (a non-instrumental principle), and hence to moral requirements themselves, can nevertheless be shown to be essential to rational agency. This argument was based on his striking doctrine that a rational will must be regarded as autonomous, or free, in the sense of being the author of the law that binds it. The fundamental principle of morality — the CI — is none other than the law of an autonomous will. Thus, at the heart of Kant’s moral philosophy is a conception of reason whose reach in practical affairs goes well beyond that of a Humean ‘slave’ to the passions. Moreover, it is the presence of this self-governing reason in each person that Kant thought offered decisive grounds for viewing each as possessed of equal worth and deserving of equal respect.

Kant’s most influential positions in moral philosophy are found in The Groundwork of the Metaphysics of Morals (hereafter, “Groundwork”) but he developed, enriched, and in some cases modified those views in later works such as The Critique of Practical Reason, The Metaphysics of Morals, Anthropology from a Pragmatic Point of View, Religion within the Boundaries of Mere Reason as well as his essays on history and related topics. Kant’s Lectures on Ethics, which were lecture notes taken by three of his students on the courses he gave in moral philosophy, also include relevant material for understanding his views. We will mainly focus on the foundational doctrines of the Groundwork, even though in recent years some scholars have become dissatisfied with this standard approach to Kant’s views and have turned their attention to the later works. We find the standard approach most illuminating, though we will highlight important positions from the later works where needed.

1. Aims and Methods of Moral Philosophy 2. Good Will, Moral Worth and Duty 3. Duty and Respect for Moral Law 4. Categorical and Hypothetical Imperatives 5. The Formula of the Universal Law of Nature 6. The Humanity Formula 7. The Autonomy Formula 8. The Kingdom of Ends Formula 9. The Unity of the Formulas 10. Autonomy 11. Virtue and Vice 12. Normative Ethical Theory 13. Teleology or Deontology? 14. Metaethics Bibliography Academic Tools

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1. Aims and Methods of Moral Philosophy

The most basic aim of moral philosophy, and so also of the Groundwork, is, in Kant’s view, to “seek out” the foundational principle of a “metaphysics of morals,” which Kant understands as a system of a priori moral principles that apply the CI to human persons in all times and cultures. Kant pursues this project through the first two chapters of the Groundwork. He proceeds by analyzing and elucidating commonsense ideas about morality, including the ideas of a “good will” and “duty”. The point of this first project is to come up with a precise statement of the principle or principles on which all of our ordinary moral judgments are based. The judgments in question are supposed to be those that any normal, sane, adult human being would accept on due rational reflection. Nowadays, however, many would regard Kant as being overly optimistic about the depth and extent of moral agreement. But perhaps he is best thought of as drawing on a moral viewpoint that is very widely shared and which contains some general judgments that are very deeply held. In any case, he does not appear to take himself to be primarily addressing a genuine moral skeptic such as those who often populate the works of moral philosophers, that is, someone who doubts that she has any reason to act morally and whose moral behavior hinges on a rational proof that philosophers might try to give. For instance, when, in the third and final chapter of the Groundwork, Kant takes up his second fundamental aim, to “establish” this foundational moral principle as a demand of each person’s own rational will, his conclusion apparently falls short of answering those who want a proof that we really are bound by moral requirements. He rests this second project on the position that we — or at least creatures with rational wills — possess autonomy. The argument of this second project does often appear to try to reach out to a metaphysical fact about our wills. This has led some readers to the conclusion that he is, after all, trying to justify moral requirements by appealing to a fact — our autonomy — that even a moral skeptic would have to recognize.

Kant’s analysis of the common moral concepts of “duty” and “good will” led him to believe that we are free and autonomous as long as morality, itself, is not an illusion. Yet in the Critique of Pure Reason, Kant also tried to show that every event has a cause. Kant recognized that there seems to be a deep tension between these two claims: If causal determinism is true then, it seems, we cannot have the kind of freedom that morality presupposes, which is “a kind of causality” that “can be active, independently of alien causes determining it” (G 4:446).

Kant thought that the only way to resolve this apparent conflict is to distinguish between phenomena, which is what we know through experience, and noumena, which we can consistently think but not know through experience. Our knowledge and understanding of the empirical world, Kant argued, can only arise within the limits of our perceptual and cognitive powers. We should not assume, however, that we know all that may be true about “things in themselves,” although we lack the “intellectual intuition” that would be needed to learn about such things.

These distinctions, according to Kant, allow us to resolve the “antinomy” about free will by interpreting the “thesis” that free will is possible as about noumena and the “antithesis” that every event has a cause as about phenomena. Morality thus presupposes that agents, in an incomprehensible “intelligible world,” are able to make things happen by their own free choices in a “sensible world” in which causal determinism is true.

Many of Kant’s commentators, who are skeptical about these apparently exorbitant metaphysical claims, have attempted to make sense of his discussions of the intelligible and sensible worlds in less metaphysically demanding ways. On one interpretation (Hudson 1994), one and the same act can be described in wholly physical terms (as an appearance) and also in irreducibly mental terms (as a thing in itself). On this compatibilist picture, all acts are causally determined, but a free act is one that can be described as determined by irreducibly mental causes, and in particular by the causality of reason. A second interpretation holds that the intelligible and sensible worlds are used as metaphors for two ways of conceiving of one and the same world (Korsgaard 1996; Allison 1990; Hill 1989a, 1989b). When we are engaging in scientific or empirical investigations, we often take

up a perspective in which we think of things as subject to natural causation, but when we deliberate, act, reason and judge, we often take up a different perspective, in which we think of ourselves and others as agents who are not determined by natural causes. When we take up this latter, practical, standpoint, we need not believe that we or others really are free, in any deep metaphysical sense; we need only operate “under the idea of freedom” (G 4:448). Controversy persists, however, about whether Kant’s conception of freedom requires a “two worlds” or “two perspectives” account of the sensible and intelligible worlds (Guyer 1987, 2009; Langton 2001; Kohl 2016; Wood 1984; Hogan 2009).

Although the two most basic aims Kant saw for moral philosophy are to seek out and establish the supreme principle of morality, they are not, in Kant’s view, its only aims. Moral philosophy, for Kant, is most fundamentally addressed to the first-person, deliberative question, “What ought I to do?”, and an answer to that question requires much more than delivering or justifying the fundamental principle of morality. We also need some account, based on this principle, of the nature and extent of the specific moral duties that apply to us. To this end, Kant employs his findings from the Groundwork in The Metaphysics of Morals, and offers a categorization of our basic moral duties to ourselves and others. In addition, Kant thought that moral philosophy should characterize and explain the demands that morality makes on human psychology and forms of human social interaction. These topics, among others, are addressed in central chapters of the second Critique, the Religion and again in the Metaphysics of Morals, and are perhaps given a sustained treatment in Anthropology from a Pragmatic Point of View. Further, a satisfying answer to the question of what one ought to do would have to take into account any political and religious requirements there are. Each of these requirement turn out to be, indirectly at least, also moral obligations for Kant, and are discussed in the Metaphysics of Morals and in Religion. Finally, moral philosophy should say something about the ultimate end of human endeavor, the Highest Good, and its relationship to the moral life. In the Critique of Practical Reason, Kant argued that this Highest Good for humanity is complete moral virtue together with complete happiness, the former being the condition of our deserving the latter. Unfortunately, Kant noted, virtue does not insure wellbeing and may even conflict with it. Further, he thought that there is no real possibility of moral perfection in this life and indeed few of us fully deserve the happiness we are lucky enough to enjoy. Reason cannot prove or disprove the existence of Divine Providence, on Kant’s view, nor the immortality of the soul, which seem necessary to rectify these things. Nevertheless, Kant argued, an unlimited amount of time to perfect ourselves (immortality) and a commensurate achievement of wellbeing (insured by God) are “postulates” required by reason when employed in moral matters.

Throughout his moral works, Kant returns time and again to the question of the method moral philosophy should employ when pursuing these aims. A basic theme of these discussions is that the fundamental philosophical issues of morality must be addressed a priori, that is, without drawing on observations of human beings and their behavior. Kant’s insistence on an a priori method to seek out and establish fundamental moral principles, however, does not always appear to be matched by his own practice. The Metaphysics of Morals, for instance, is meant to be based on a priori rational principles, but many of the specific duties that Kant describes, along with some of the arguments he gives in support of them, rely on general facts about human beings and our circumstances that are known from experience.

In one sense, it might seem obvious why Kant insists on an a priori method. A “metaphysics of morals” would be, more or less, an account of the nature and structure of moral requirements — in effect, a categorization of duties and values. Such a project would address such questions as, What is a duty? What kinds of duties are there? What is the good? What kinds of goods are there?, and so on. These appear to be metaphysical questions. Any principle used to provide such categorizations appears to be a principle of metaphysics, in a sense, but Kant did not see them as external moral truths that exist independently of rational agents. Moral requirements, instead, are rational principles that tell us what we have overriding reason to do. Metaphysical principles of this sort are always sought out and established by a priori methods.

Perhaps something like this was behind Kant’s thinking. However, the considerations he offers for an a priori method do not all obviously draw on this sort of rationale. The following are three considerations favoring a priori methods that he emphasizes repeatedly.

The first is that, as Kant and others have conceived of it, ethics initially requires an analysis of our moral concepts. We must understand the concepts of a “good will”, “obligation”, “duty” and so on, as well as their logical relationships to one another, before we can determine whether our use of these concepts is justified. Given that the analysis of concepts is an a priori matter, to the degree that ethics consists of such an analysis, ethics is a priori as a well.

Of course, even were we to agree with Kant that ethics should begin with analysis, and that analysis is or should be an entirely a priori undertaking, this would not explain why all of the fundamental questions of moral philosophy must be pursued a priori. Indeed, one of the most important projects of moral philosophy, for Kant, is to show that we, as rational agents, are bound by moral requirements and that fully rational agents would necessarily comply with them. Kant admits that his analytical arguments for the CI are inadequate on their own because the most they can show is that the CI is the supreme principle of morality if there is such a principle. Kant must therefore address the possibility that morality itself is an illusion by showing that the CI really is an unconditional requirement of reason that applies to us. Even though Kant thought that this project of “establishing” the CI must also be carried out a priori, he did not think we could pursue this project simply by analyzing our moral concepts or examining the actual behavior of others. What is needed, instead, is a “synthetic”, but still a priori, kind of argument that starts from ideas of freedom and rational agency and critically examines the nature and limits of these capacities.

This is the second reason Kant held that fundamental issues in ethics must be addressed with an a priori method: The ultimate subject matter of ethics is the nature and content of the principles that necessarily determine a rational will.

Fundamental issues in moral philosophy must also be settled a priori because of the nature of moral requirements themselves, or so Kant thought. This is a third reason he gives for an a priori method, and it appears to have been of great importance to Kant: Moral requirements present themselves as being unconditionally necessary. But an a posteriori method seems ill-suited to discovering and establishing what we must do whether we feel like doing it or not; surely such a method could only tell us what we actually do. So an a posteriori method of seeking out and establishing the principle that generates such requirements will not support the presentation of moral “oughts” as unconditional necessities. Kant argued that empirical observations could only deliver conclusions about, for instance, the relative advantages of moral behavior in various circumstances or how pleasing it might be in our own eyes or the eyes of others. Such findings clearly would not support the unconditional necessity of moral requirements. To appeal to a posteriori considerations would thus result in a tainted conception of moral requirements. It would view them as demands for which compliance is not unconditionally necessary, but rather necessary only if additional considerations show it to be advantageous, optimific or in some other way felicitous. Thus, Kant argued that if moral philosophy is to guard against undermining the unconditional necessity of obligation in its analysis and defense of moral thought, it must be carried out entirely a priori.

2. Good Will, Moral Worth and Duty

Kant’s analysis of commonsense ideas begins with the thought that the only thing good without qualification is a “good will”. While the phrases “he’s good hearted”, “she’s good natured” and “she means well” are common, “the good will” as Kant thinks of it is not the same as any of these ordinary notions. The idea of a good will is closer to the idea of a “good person”, or, more archaically, a “person of good will”. This use of the term “will” early on in analyzing ordinary moral thought prefigures later and more technical discussions concerning the nature of rational agency. Nevertheless, this idea of a good will is an important commonsense touchstone to which Kant returns throughout his works. The basic idea, as Kant describes it in the Groundwork, is that what makes a good person good is his possession of a will that is in a certain way “determined” by, or makes its decisions on the basis of, the moral law. The idea of a good will is supposed to be the idea of one who is committed only to make decisions that she holds to be morally worthy and who takes moral considerations in themselves to be conclusive reasons for guiding her behavior. This sort of disposition or character is something we all highly value, Kant thought. He believes we value it without limitation or qualification. By this, we believe, he means primarily two things.

First, unlike anything else, there is no conceivable circumstance in which we regard our own moral goodness as worth forfeiting simply in order to obtain some desirable object. By contrast, the value of all other desirable qualities, such as courage or cleverness, can be diminished, forgone, or sacrificed under certain circumstances: Courage may be laid aside if it requires injustice, and it is better not to be witty if it requires cruelty. There is no implicit restriction or qualification to the effect that a commitment to give moral considerations decisive weight is worth honoring, but only under such and such circumstances.

Second, possessing and maintaining a steadfast commitment to moral principles is the very condition under which anything else is worth having or pursuing. Intelligence and even pleasure are worth having only on the condition that they do not require giving up one’s fundamental moral convictions. The value of a good will thus cannot be that it secures certain valuable ends, whether of our own or of others, since their value is entirely conditional on our possessing and maintaining a good will. Indeed, since a good will is good under any condition, its goodness must not depend on any particular conditions obtaining. Thus, Kant points out that a good will must then also be good in itself and not in virtue of its relationship to other things such as the agent’s own happiness, overall welfare or any other effects it may or may not produce A good will would still “shine like a jewel” even if it were “completely powerless to carry out its aims” (G 4:394).

In Kant’s terms, a good will is a will whose decisions are wholly determined by moral demands or, as he often refers to this, by the Moral Law. Human beings inevitably feel this Law as a constraint on their natural desires, which is why such Laws, as applied to human beings, are imperatives and duties. A human will in which the Moral Law is decisive is motivated by the thought of duty. A holy or divine will, if it exists, though good, would not be good because it is motivated by thoughts of duty because such a will does not have natural inclinations and so necessarily fulfills moral requirements without feeling constrained to do so. It is the presence of desires that could operate independently of moral demands that makes goodness in human beings a constraint, an essential element of the idea of “duty.” So in analyzing unqualified goodness as it occurs in imperfectly rational creatures such as ourselves, we are investigating the idea of being motivated by the thought that we are constrained to act in certain ways that we might not want to simply from the thought that we are morally required to do so.

Kant confirms this by comparing motivation by duty with other sorts of motives, in particular, with motives of self-interest, self-preservation, sympathy and happiness. He argues that a dutiful action from any of these motives, however praiseworthy it may be, does not express a good will. Assuming an action has moral worth only if it expresses a good will, such actions have no genuine “moral worth.” The conformity of one’s action to duty in such cases is only related by accident to morality. For instance, if one is motivated by happiness alone, then had conditions not conspired to align one’s duty with one’s own happiness one would not have done one’s duty. By contrast, were one to supplant any of these motivations with the motive of duty, the morality of the action would then express one’s determination to act dutifully out of respect for the moral law itself. Only then would the action have moral worth.

Kant’s views in this regard have understandably been the subject of much controversy. Many object that we do not think better of actions done for the sake of duty than actions performed out of emotional concern or sympathy for others, especially those things we do for friends and family. Worse, moral worth appears to require not only that one’s actions be motivated by duty, but also that no other motives, even love or friendship, cooperate. Yet Kant’s defenders have argued that his point is not that we do not admire or praise motivating concerns other than duty, only that from the point of view of someone deliberating about what to do, these concerns are not decisive in the way that considerations of moral duty are. What is crucial in actions that express a good will is that in conforming to duty a perfectly virtuous person always would, and so ideally we should, recognize and be moved by the thought that our conformity is morally obligatory. The motivational structure of the agent should be arranged so that she always treats considerations of duty as sufficient reasons for conforming to those requirements. In other words, we should have a firm commitment not to perform an action if it is morally forbidden and to perform an action if it is morally required. Having a good will, in this sense, is compatible with having feelings and emotions of various kinds, and even with aiming to cultivate some of them in order to counteract desires and inclinations that tempt us to immorality. Controversy persists, however, about

whether Kant’s claims about the motive of duty go beyond this basic point (Timmermann 2007; Herman 1993; Wood 1998; Baron 1995).

Suppose for the sake of argument we agree with Kant. We now need to know what distinguishes the principle that lays down our duties from these other motivating principles, and so makes motivation by it the source of unqualified value.

3. Duty and Respect for Moral Law

According to Kant, what is singular about motivation by duty is that it consists of bare respect for the moral law. What naturally comes to mind is this: Duties are rules or laws of some sort combined with some sort of felt constraint or incentive on our choices, whether from external coercion by others or from our own powers of reason. For instance, the bylaws of a club lay down duties for its officers and enforce them with sanctions. City and state laws establish the duties of citizens and enforce them with coercive legal power. Thus, if we do something because it is our “civic” duty, or our duty “as a boy scout” or “a good American,” our motivation is respect for the code that makes it our duty. Thinking we are duty bound is simply respecting, as such, certain laws pertaining to us.

However intuitive, this cannot be all of Kant’s meaning. For one thing, as with the Jim Crow laws of the old South and the Nuremberg laws of Nazi Germany, the laws to which these types of “actions from duty” conform may be morally despicable. Respect for such laws could hardly be thought valuable. For another, our motive in conforming our actions to civic and other laws is rarely unconditional respect. We also have an eye toward doing our part in maintaining civil or social order, toward punishments or loss of standing and reputation in violating such laws, and other outcomes of lawful behavior. Indeed, we respect these laws to the degree, but only to the degree, that they do not violate values, laws or principles we hold more dear. Yet Kant thinks that, in acting from duty, we are not at all motivated by a prospective outcome or some other extrinsic feature of our conduct except insofar as these are requirements of duty itself. We are motivated by the mere conformity of our will to law as such.

To act out of respect for the moral law, in Kant’s view, is to be moved to act by a recognition that the moral law is a supremely authoritative standard that binds us and to experience a kind of feeling, which is akin to awe and fear, when we acknowledge the moral law as the source of moral requirements. Human persons inevitably have respect for the moral law even though we are not always moved by it and even though we do not always comply with the moral standards that we nonetheless recognize as authoritative.

Kant’s account of the content of moral requirements and the nature of moral reasoning is based on his analysis of the unique force moral considerations have as reasons to act. The force of moral requirements as reasons is that we cannot ignore them no matter how circumstances might conspire against any other consideration. Basic moral requirements retain their reason-giving force under any circumstance, they have universal validity. So, whatever else may be said of basic moral requirements, their content is universal. Only a universal law could be the content of a requirement that has the reason-giving force of morality. This brings Kant to a preliminary formulation of the CI: “I ought never to act except in such a way that I could also will that my maxim should become a universal law” (G 4:402). This is the principle which motivates a good will, and which Kant holds to be the fundamental principle of all of morality.

4. Categorical and Hypothetical Imperatives

Kant holds that the fundamental principle of our moral duties is a categorical imperative. It is an imperative because it is a command addressed to agents who could follow it but might not (e.g. , “Leave the gun. Take the cannoli.”). It is categorical in virtue of applying to us unconditionally, or simply because we possesses rational wills, without reference to any ends that we might or might not have. It does not, in other words, apply to us on the condition that we have antecedently adopted some goal for ourselves.

There are “oughts” other than our moral duties, according to Kant, but these oughts are distinguished from the moral ought in being based on a quite different kind of principle, one that is the source of hypothetical imperatives. A hypothetical imperative is a command that also applies to us in virtue of our having a rational will, but not simply in virtue of this. It requires us to exercise our wills in a certain way given we have antecedently willed an end. A hypothetical imperative is thus a command in a conditional form. But not any command in this form counts as a hypothetical imperative in Kant’s sense. For instance, “if you’re happy and you know it, clap your hands!” is a conditional command. But the antecedent conditions under which the command “clap your hands” applies to you do not posit any end that you will, but consist rather of emotional and cognitive states you may or may not be in. Further, “if you want pastrami, try the corner deli” is also a command in conditional form, but strictly speaking it too fails to be a hypothetical imperative in Kant’s sense since this command does not apply to us in virtue of our willing some end, but only in virtue of our desiring or wanting an end. For Kant, willing an end involves more than desiring; it requires actively choosing or committing to the end rather than merely finding oneself with a passive desire for it. Further, there is nothing irrational in failing to will means to what one desires. An imperative that applied to us in virtue of our desiring some end would thus not be a hypothetical imperative of practical rationality in Kant’s sense.

The condition under which a hypothetical imperative applies to us, then, is that we will some end. Now, for the most part, the ends we will we might not have willed, and some ends that we do not will we might nevertheless have willed. But there is at least conceptual room for the idea of a natural or inclination-based end that we must will. The distinction between ends that we might or might not will and those, if any, we necessarily will as the kinds of natural beings we are, is the basis for his distinction between two kinds of hypothetical imperatives. Kant names these “problematic” and “assertoric”, based on how the end is willed. If the end is one that we might or might not will — that is, it is a merely possible end — the imperative is problematic. For instance, “Don’t ever take side with anyone against the Family.” is a problematic imperative, even if the end posited here is (apparently) one’s own continued existence. Almost all non-moral, rational imperatives are problematic, since there are virtually