Moral Realism and Antirealism

Whether there are objective moral facts — and what their existence or absence would mean for ethical thought and talk.

Definition

Moral realism is the view that there are objective moral facts, and that at least some moral claims are literally true in virtue of those facts; antirealism denies the existence of such mind-independent moral facts, whether by holding that moral claims are systematically false (error theory) or by reconstruing their function as non-fact-stating.

Scope

This area covers the central ontological debate of metaethics: do moral properties and facts exist mind-independently, the way physical facts are taken to, or are moral claims projections of human attitudes, conventions, or errors? It surveys robust (non-naturalist) realism, naturalist realism, and the family of antirealist positions — error theory, projectivism, quasi-realism, and constructivism — together with the arguments that divide them, including the argument from disagreement and the 'queerness' objection.

Sub-topics

• Moral Antirealism and Error Theory
• Response-Dependence and Quasi-Realism
• Robust Moral Realism
• The Argument from Disagreement

Core questions

• Are there moral facts, and if so are they mind-independent?
• If moral claims aim to describe facts, are any of them ever true?
• Does widespread and persistent moral disagreement count against the existence of objective moral facts?
• Can a realist explain how we come to know moral facts, and an antirealist explain the apparent objectivity of moral discourse?

Key concepts

• mind-independence
• objectivity
• moral facts and properties
• argument from queerness
• argument from disagreement
• stance-independence

Key theories

Robust (non-naturalist) moral realism

There are mind-independent moral facts that are not reducible to natural facts; moral properties are real but sui generis.

Moral error theory

Moral claims purport to state objective facts but there are no such facts, so all positive moral claims are uniformly false.

Quasi-realism

Starting from an expressivist account of moral judgement, it aims to earn the right to realist-sounding talk of moral truth, facts, and knowledge without positing mind-independent moral facts.

History

The modern realism debate is often dated to G. E. Moore's anti-naturalism early in the twentieth century, but its sharpest contemporary form emerged after J. L. Mackie's 1977 argument that ordinary moral thought presupposes objective values that do not exist. The 1980s and 1990s saw a vigorous realist revival — Boyd's and Brink's naturalist realism, Shafer-Landau's non-naturalism — answered by Blackburn's quasi-realist reconstruction of antirealism.

Debates

The argument from queerness

Mackie argued that objective values would have to be metaphysically and epistemologically 'queer' — unlike anything else in the universe — giving reason to doubt they exist; realists reply that the charge either begs the question or proves too much.

Whether disagreement undermines realism

Antirealists treat deep, persistent moral disagreement as evidence against objective moral facts, while realists argue such disagreement is explicable by non-moral error, bias, and differing circumstances.

Key figures

• J. L. Mackie
• Russ Shafer-Landau
• David Brink
• Simon Blackburn
• Geoffrey Sayre-McCord

Seminal works

• mackie1977
• shaferlandau2003
• brink1989
• blackburn1993

Frequently asked questions

Is moral realism the same as moral absolutism?

No. Moral realism is a claim about whether moral facts exist objectively; absolutism is a normative claim that some acts are always wrong. A realist can hold that moral truths are context-sensitive, and an antirealist could still endorse exceptionless rules.

Does antirealism imply that anything goes?

Not necessarily. Quasi-realists and constructivists argue that one can preserve robust moral standards, criticism, and improvement without positing mind-independent moral facts.