Error Theory of Ethics
ERROR THEORY OF ETHICS
An "error theory of ethics" is the view that the ordinary user of moral language is typically making claims that involve a mistake. The concepts of ethics introduce a mistaken, erroneous, way of thinking of the world or of conducting practical reasoning. The theory was most influentially proposed by John L. Mackie in his book Ethics: Inventing Right and Wrong (1977). Mackie believed that ordinary moral claims presuppose that there are objective moral values, but there are no such things. Hence, the practice of morality is founded upon a metaphysical error.
Mackie's arguments against the existence of objective values are of two main kinds. One is the argument from relativity, which cites the familiar phenomenon of ethical disagreement. Another is the argument from "queerness." The moral values whose existence Mackie denies are presented as metaphysically strange facts. They are facts with a peculiar necessity built into them: their essence is that they make demands or exist as laws that "must" be obeyed. In Kantian terms, the demands made by morality are thought of as categorical, "not contingent upon any desire or preference or policy or choice." The foundation of any such demands or laws in the natural world is entirely obscure. Hence, the right response of a naturalist is to deny that there can be such things. It should be noticed that this is not supposed to be an argument against any particular morality, for instance, one demanding honesty or fidelity, but against the entire scheme of thought of which particular ethical systems are examples.
Another influential theorist whose work bears some resemblance to Mackie's is Bernard Williams, whose Ethics and the Limits of Philosophy (1985) equally raises the doubt that ethics cannot possibly be what it purports to be, although Williams's own arguments are more specifically targeted on the morality of duty and obligation.
Responses to the error theory have taken several forms. Both the argument from relativity and that from queerness have been queried, the former on the grounds that, even if ethical opinions differ fundamentally, this does not prevent one from being right and the others wrong, and the latter mainly on the grounds that Mackie suffered from an oversimple, "scientistic" conception of the kind of thing a moral fact would have to be. Perhaps more fundamentally, it is not clear what clean, error-free practice the error theorist would wish to substitute for old, error-prone ethics. That is, assuming that people living together have a need for shared practical norms, then some way of expressing and discussing those norms seems to be needed, and this is all that ethics requires. Mackie himself saw that ethics was not a wholly illegitimate branch of thought, for he gave a broadly Humean picture of its function in human life. Even projectivists maintain that our need to express attitudes, coordinate policies, and censure transgressions is a sufficient justification for thinking in terms of ethical demands. Ethics does not invoke a strange world of metaphysically dubious facts but serves a natural human need.
Mackie, J. L. Ethics: Inventing Right and Wrong. Middlesex, U.K.: Penguin, 1977.
Williams, B. Ethics and the Limits of Philosophy. Cambridge, MA: Harvard University Press, 1985.
Simon Blackburn (1996)