Moral epistemology the discipline, at the intersection of ethics and epistemology, that studies the epistemic status and relations of moral judgments and principles. It has developed out of an interest, common to both ethics and epistemology, in questions of justification and justifiability – in epistemology, of statements or beliefs, and in ethics, of actions as well as judgments of actions and also general principles of judgment. Its most prominent questions include the following. Can normative claims be true or false? If so, how can they be known to be true or false? If not, what status do they have, and are they capable of justification? If they are capable of justification, how can they be justified? Does the justification of normative claims differ with respect to particular claims and with respect to general principles?
In epistemology recent years have seen a tendency to accept as valid an account of knowledge as entailing justified true belief, a conception that requires an account not just of truth but also of justification and of justified belief. Thus, under what conditions is someone justified, epistemically, in believing something? Justification, of actions, of judgments, and of principles, has long been a central element in ethics. It is only recently that justification in ethics came to be thought of as an epistemological problem, hence ‘moral epistemology’, as an expression, is a fairly recent coinage, although its problems have a long lineage.
One long-standing linkage is provided by the challenge of skepticism. Skepticism in ethics can be about the existence of any genuine distinction between right and wrong, or it can focus on the possibility of attaining any knowledge of right and wrong, good or bad. Is there a right answer? is a question in the metaphysics of ethics. Can we know what the right answer is, and if so how? is one of moral epistemology. Problems of perception and observation and ones about observation statements or sense-data play an important role in epistemology. There is not any obvious parallel in moral epistemology, unless it is the role of prereflective moral judgments, or commonsense moral judgments – moral judgments unguided by any overt moral theory – which can be taken to provide the data of moral theory, and which need to be explained, systematized, coordinated, or revised to attain an appropriate relation between theory and data. This would be analogous to taking the data of epistemology to be provided, not by sense-data or observations but by judgments of perception or observation statements. Once this step is taken the parallel is very close. One source of moral skepticism is the apparent lack of any observational counterpart for moral predicates, which generates the question how moral judgments can be true if there is nothing for them to correspond to. Another source of moral skepticism is apparently constant disagreement and uncertainty, which would appear to be explained by the skeptical hypothesis denying the reality of moral distinctions. Noncognitivism in ethics maintains that moral judgments are not objects of knowledge, that they make no statements capable of truth or falsity, but are or are akin to expressions of attitudes. Some other major differences among ethical theories are largely epistemological in character. Intuitionism maintains that basic moral propositions are knowable by intuition. Empiricism in ethics maintains that moral propositions can be established by empirical means or are complex forms of empirical statements. Ethical rationalism maintains that the fundamental principle(s) of morality can be established a priori as holding of necessity. This is exemplified by Kant’s moral philosophy, in which the categorical imperative is regarded as synthetic a priori; more recently by what Alan Gewirth (b.1912) calls the ‘principle of generic consistency,’ which he claims it is selfcontradictory to deny. Ethical empiricism is exemplified by classical utilitarianism, such as that of Bentham, which aspires to develop ethics as an empirical science. If the consequences of actions can be scientifically predicted and their utilities calculated, then ethics can be a science. Situationism is equivalent to concrete case intuitionism in maintaining that we can know immediately what ought to be done in specific cases, but most ethical theories maintain that what ought to be done is, in J. S. Mill’s words, determined by ‘the application of a law to an individual case.’ Different theories differ on the epistemic status of these laws and on the process of application. Deductivists, either empiricistic or rationalistic, hold that the law is essentially unchanged in the application; non-deductivists hold that the law is modified in the process of application. (This distinction is explained in F. L. Will [1909–98], Beyond Deduction, 1988.) There is similar variation about what if anything is selfevident, Sidgwick maintaining that only certain highly abstract principles are self-evident, Ross that only general rules are, and Prichard that only concrete judgments are, ‘by an act of moral thinking.’ Other problems in moral epistemology are provided by the fact–value distinction – and controversies about whether there is any such distinction – and the is–ought question, the question how a moral judgment can be derived from statements of fact alone. Naturalists affirm the possibility, non-naturalists deny it. Prescriptivists claim that moral judgments are prescriptions and cannot be deduced from descriptive statements alone. This question ultimately leads to the question how an ultimate principle can be justified. If it cannot be deduced from statements of fact, that route is out; if it must be deduced from some other moral principle, then the principle deduced cannot be ultimate and in any case this process is either circular or leads to an infinite regress. If the ultimate principle is self-evident, then the problem may have an answer. But if it is not it would appear to be arbitrary. The problem of the justification of an ultimate principle continues to be a leading one in moral epistemology.
Recently there has been much interest in the status and existence of ‘moral facts.’ Are there any, what are they, and how are they established as ‘facts’? This relates to questions about moral realism. Moral realism maintains that moral predicates are real and can be known to be so; anti-realists deny this. This denial links with the view that moral properties supervene on natural ones, and the problem of supervenience is another recent link between ethics and epistemology.
Pragmatism in ethics maintains that a moral problem is like any problem in that it is the occasion for inquiry and moral judgments are to be regarded as hypotheses to be tested by how well they resolve the problem. This amounts to an attempt to bypass the is–ought problem and all such ‘dualisms.’ So is constructivism, a development owing much to the work of Rawls, which contrasts with moral realism. Constructivism maintains that moral ideas are human constructs and the task is not epistemological or metaphysical but practical and theoretical – that of attaining reflective equilibrium between considered moral judgments and the principles that coordinate and explain them. On this view there are no moral facts. Opponents maintain that this only replaces a foundationalist view of ethics with a coherence conception.
The question whether questions of moral epistemology can in this way be bypassed can be regarded as itself a question of moral epistemology. And the question of the foundations of morality, and whether there are foundations, can still be regarded as a question of moral epistemology, as distinct from a question of the most convenient and efficient arrangement of our moral ideas.
See also ETHICAL CONSTRUCTIVISM , ETHICS , INTUITION , MORAL REALISM , REFLEC – TIVE EQUILIBRIU. M.G.S.