moral principles are taken to be laws issued by God to humanity, and their authority thus derives from God’s supremacy. The theory is the original Christian source of the principles’ jural conception. The rise of secular thought since the Enlightenment has, however, limited its appeal. Later examples, which continue to attract broad interest and discussion, are formalism and contractarianism. Formalism is best exemplified in Kant’s ethics. It takes a moral principle to be a precept that satisfies the formal criteria of a universal law, and it takes formal criteria to be the marks of pure reason. Consequently, moral principles are laws that issue from reason. As Kant puts it, they are laws that we, as rational beings, give to ourselves and that regulate our conduct insofar as we engage each other’s rational nature. They are laws for a republic of reason or, as Kant says, a kingdom of ends whose legislature comprises all rational beings. Through this ideal, Kant makes intelligible and forceful the otherwise obscure notion that moral principles derive their authority from the sovereignty of reason. Contractarianism also draws inspiration from Kant’s ethics as well as from the social contract theories of Locke and Rousseau. Its fullest and most influential statement appears in the work of Rawls. On this view, moral principles represent the ideal terms of social cooperation for people who live together in fellowship and regard each other as equals. Specifically, they are taken to be the conditions of an ideal agreement among such people, an agreement that they would adopt if they met as an assembly of equals to decide collectively on the social arrangements governing their relations and reached their decision as a result of open debate and rational deliberation. The authority of moral principles derives, then, from the fairness of the procedures by which the terms of social cooperation would be arrived at in this hypothetical constitutional convention and the assumption that any rational individual who wanted to live peaceably with others and who imagined himself a party to this convention would, in view of the fairness of its procedures, assent to its results. It derives, that is, from the hypothetical consent of the governed.
Philosophers who think of a moral code on the model of a technical system of an applied science use an entirely different method of justification. In their view, just as the principles of medicine represent knowledge about how best to promote health, so the principles of right and wrong represent knowledge about how best to promote the ends of morality. These philosophers, then, have a teleological conception of the code. Our fundamental duty is to promote certain ends, and the principles of right and wrong organize and direct our efforts in this regard. What justifies the principles, on this view, is that the ends they serve are the right ones to promote and the actions they prescribe are the best ways to promote them. The principles are authoritative, in other words, in virtue of the wisdom of their prescriptions.
Different teleological views in the theory of duty correspond to different answers to the question of what the right ends to promote are. The most common answer is happiness; and the main division among the corresponding views mirrors the distinction in the theory of intrinsic value between egoism and universalism. Thus, egoism and universalism in the theory of duty hold, respectively, that the fundamental duty of morality is to promote, as best as one can, one’s own happiness and that it is to promote, as best as one can, the happiness of humanity. The former is ethical egoism and is based on the ideal of rational self-love. The latter is utilitarianism and is based on the ideal of rational benevolence. Ethical egoism’s most famous exponents in modern philosophy are Hobbes and Spinoza. It has had few distinguished defenders since their time. Bentham and J. S. Mill head the list of distinguished defenders of utilitarianism. The view continues to be enormously influential. On these teleological views, answers to questions about the ends we ought to pursue determine the principles of right and wrong. Put differently, the general study of right action, on these views, is subordinate to the general study of goodness. This is one of the two leading answers to the structural question about how the two studies are related. The other is that the general study of right action is to some extent independent of the general study of goodness. On views that represent this answer, some principles of right and wrong, notably principles of justice and honesty, prescribe actions even though more evil than good would result from doing them. These views are deontological. Fiat justitia ruat coelum captures their spirit. The opposition between teleology and deontology in ethics underlies many of the disputes in the general study of right action. The principal substantive and structural questions of ethics arise not only with respect to the conduct of human life generally but also with respect to specific walks of life such as medicine, law, journalism, engineering, and business. The examination of these questions in relation to the common practices and traditional codes of such professions and occupations has resulted in the special studies of applied ethics. In these studies, ideas and theories from the general studies of goodness and right action are applied to particular circumstances and problems of some profession or occupation, and standard philosophical techniques are used to define, clarify, and organize the ethical issues found in its domain. In medicine, in particular, where rapid advances in technology create, overnight, novel ethical problems on matters of life and death, the study of biomedical ethics has generated substantial interest among practitioners and scholars alike. Metaethics. To a large extent, the general studies of goodness and right action and the special studies of applied ethics consist in systematizing, deepening, and revising our beliefs about how we ought to conduct our lives. At the same time, it is characteristic of philosophers, when reflecting on such systems of belief, to examine the nature and grounds of these beliefs. These questions, when asked about ethical beliefs, define the field of metaethics. The relation of this field to the other studies is commonly represented by taking the other studies to constitute the field of ethics proper and then taking metaethics to be the study of the concepts, methods of justification, and ontological assumptions of the field of ethics proper.
Accordingly, metaethics can proceed from either an interest in the epistemology of ethics or an interest in its metaphysics. On the first approach, the study focuses on questions about the character of ethical knowledge. Typically, it concentrates on the simplest ethical beliefs, such as ‘Stealing is wrong’ and ‘It is better to give than to receive’, and proceeds by analyzing the concepts in virtue of which these beliefs are ethical and examining their logical basis. On the second approach, the study focuses on questions about the existence and character of ethical properties. Typically, it concentrates on the most general ethical predicates such as goodness and wrongfulness and considers whether there truly are ethical properties represented by these predicates and, if so, whether and how they are interwoven into the natural world. The two approaches are complementary. Neither dominates the other.
The epistemological approach is comparative. It looks to the most successful branches of knowledge, the natural sciences and pure mathematics, for paradigms. The former supplies the paradigm of knowledge that is based on observation of natural phenomena; the latter supplies the paradigm of knowledge that seemingly results from the sheer exercise of reason. Under the influence of these paradigms, three distinct views have emerged: naturalism, rationalism, and noncognitivism.
Naturalism takes ethical knowledge to be empirical and accordingly models it on the paradigm of the natural sciences. Ethical concepts, on this view, concern natural phenomena. Rationalism takes ethical knowledge to be a priori and accordingly models it on the paradigm of pure mathematics. Ethical concepts, on this view, concern morality understood as something completely distinct from, though applicable to, natural phenomena, something whose content and structure can be apprehended by reason independently of sensory inputs. Noncognitivism, in opposition to these other views, denies that ethics is a genuine branch of knowledge or takes it to be a branch of knowledge only in a qualified sense. In either case, it denies that ethics is properly modeled on science or mathematics. On the most extreme form of noncognitivism, there are no genuine ethical concepts; words like ‘right’, ‘wrong’, ‘good’, and ‘evil’ have no cognitive meaning but rather serve to vent feelings and emotions, to express decisions and commitments, or to influence attitudes and dispositions. On less extreme forms, these words are taken to have some cognitive meaning, but conveying that meaning is held to be decidedly secondary to the purposes of venting feelings, expressing decisions, or influencing attitudes. Naturalism is well represented in the work of Mill; rationalism in the works of Kant and the intuitionists. And noncognitivism, which did not emerge as a distinctive view until the twentieth century, is most powerfully expounded in the works of C. L. Stevenson and Hare. Its central tenets, however, were anticipated by Hume, whose skeptical attacks on rationalism set the agenda for subsequent work in metaethics. The metaphysical approach is centered on the question of objectivity, the question of whether ethical predicates represent real properties of an external world or merely apparent or invented properties, properties that owe their existence to the perception, feeling, or thought of those who ascribe them. Two views dominate this approach. The first, moral realism, affirms the real existence of ethical properties.