Are moral facts discovered or invented? Twenty-five centuries, no resolution.
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Characterization
Moral realism holds that moral statements — "cruelty is wrong," "justice is good" — can be objectively true or false, independent of what any person or culture believes. Moral anti-realism denies this: moral claims are expressions of attitude (emotivism, A. J. Ayer), prescriptions for action (prescriptivism, R. M. Hare), or useful fictions (moral fictionalism, Richard Joyce). The question is as old as philosophy. Plato argued in the Republic that the Good is a Form — an objective feature of reality, discoverable by reason. Hume argued in the Treatise (1739) that moral judgements arise from sentiment, not reason, and that no "ought" can be derived from an "is." G. E. Moore's Principia Ethica (1903) identified the naturalistic fallacy: the error of equating goodness with any natural property. J. L. Mackie's Ethics: Inventing Right and Wrong (1977) argued that if moral facts existed, they would be metaphysically "queer" — utterly unlike anything else in the natural world. Derek Parfit's On What Matters (2011) attempted a grand synthesis, arguing that the three major ethical traditions — Kantian, consequentialist, and contractualist — converge on the same truths. The debate continues, unresolved, in contemporary metaethics. The Academy hosts Moral Realism in the Heart School because it asks the question that underlies every game with rules: are the rules of the moral game discovered or invented? And does the answer matter for how we play?
Lineage
Plato, Republic, Book VI (c. 380 BCE). David Hume, A Treatise of Human Nature, Book III (1739). G. E. Moore, Principia Ethica (Cambridge University Press, 1903). A. J. Ayer, Language, Truth and Logic (Gollancz, 1936). J. L. Mackie, Ethics: Inventing Right and Wrong (Penguin, 1977). Derek Parfit, On What Matters (Oxford University Press, 2011). The Cornell realism of Nicholas Sturgeon and Richard Boyd. Russ Shafer-Landau, Moral Realism: A Defence (Oxford University Press, 2003).
Quests
The Magus
Design a thought experiment or hypothetical scenario that could, in principle, distinguish between moral realism and moral anti-realism — a situation where the two positions would generate clearly different predictions or prescriptions. If you believe no such scenario is possible, argue why and explain what this impossibility itself tells us about the nature of moral disagreement.
The Adventurer
Identify three moral convictions you hold with near-certainty (e.g., "torturing innocents for amusement is wrong"). For each, examine: Does this conviction feel like a discovery about the world (realism) or an expression of your deepest commitments (anti-realism)? Can you imagine a coherent culture that denies it? What would it take to change your mind? Record your findings and reflect on whether introspection can settle the realism question.
The Sage
Construct a clear, structured guide to the major positions in the moral realism debate: Moore's non-naturalism, Mackie's error theory, Cornell realism (Sturgeon, Boyd), constructivism (Rawls, Korsgaard), expressivism (Gibbard, Blackburn), and Parfit's convergence thesis. For each position, state its core claim, its strongest argument, and the objection it has most struggled to answer.