Questions: Moral Error Theory

Question 1

How does Mackie's moral error theory differ from expressivism?

• A. Both deny objective moral facts, but expressivism limits this to positive moral claims while error theory applies to all moral claims
• B. Error theory holds that moral claims are genuine truth-apt propositions that are all false; expressivism holds that moral claims are not truth-apt propositions at all
• C. Expressivism says all moral claims are false; error theory says we cannot know whether they are true or false
• D. They are the same position, just stated in different philosophical vocabularies

Answer: (B)

This is the crucial distinction. Expressivists (like Ayer and Blackburn) deny that 'torture is wrong' is a genuine truth-apt claim — it expresses an attitude, not a proposition. Mackie disagrees: he thinks such claims really do purport to describe objective features of reality (they are truth-apt). He just thinks no such features exist. So both reach anti-realist conclusions, but by completely different routes: expressivism by revising the semantics of moral language, error theory by accepting the realist semantics and then pointing out that the world fails to satisfy it.

Question 2

Mackie's 'argument from queerness' supports error theory by claiming that:

• A. Moral terms are logically self-contradictory
• B. Objective moral facts would need to be non-physical, intrinsically motivating entities unlike anything else in our ontology — entities that Occam's razor argues we should not posit
• C. Different cultures have incompatible moral beliefs, proving that morality is socially constructed
• D. Moral language evolved for social coordination purposes, not to track facts

Answer: (B)

The argument from queerness is Mackie's main metaphysical argument. Objective moral facts, if they existed, would be strange beyond anything else we believe in: non-physical, not empirically detectable, yet somehow intrinsically motivating to rational agents simply by being perceived. We would need a special moral faculty with no natural explanation. Since we can explain moral behavior, disagreement, and motivation without positing such entities, Occam's razor says we should not. The argument does not rely on cultural relativism (option C) or evolutionary debunking (option D) — these are distinct arguments.

Question 3

According to error theory, when someone sincerely asserts 'cruelty is wrong,' they are making a genuine truth-apt claim — one that is systematically false.

• T. True
• F. False

Answer: True

This is error theory's striking claim. Unlike expressivism, Mackie accepts that 'cruelty is wrong' purports to state an objective fact about cruelty — it is not just an expression of disapproval. But since no objective moral facts exist (nothing in the world has the property of objective wrongness), the claim fails to refer to anything real. Every positive moral claim that presupposes such facts is, on this view, false in the same way as 'the present king of France is bald' — it fails because its presuppositions are unsatisfied.

Question 4

Mackie's error theory implies we should abandon moral practices, since there are no objective moral facts to ground them.

• T. True
• F. False

Answer: False

This is a common and important misconception. Mackie distinguished between his metaethical thesis (what moral language presupposes) and practical ethics (how we should live). He thought we should *invent* rather than discover moral systems, but that this invention is both necessary and worthwhile — moral frameworks help coordinate behavior, resolve conflicts, and support human flourishing without needing metaphysical grounding. Error theory is not nihilism; it diagnoses a false presupposition in moral language without recommending that we stop caring about ethics.

Question 5

What is the 'argument from queerness,' and why does Mackie think it counts against the existence of objective moral facts?

Model answer: The argument from queerness holds that objective moral facts, if they existed, would be deeply strange entities — non-physical, not empirically detectable, yet intrinsically motivating to any rational agent who perceived them. This combination of properties is unlike anything else in our ontology. We would need a special moral faculty with no natural explanation to access such facts. Occam's razor argues against positing them: we can fully explain moral language, disagreement, and motivation without them.

The argument has both a metaphysical and an epistemological dimension. Metaphysically: what kind of thing would an objective moral fact be? It would have to be both descriptive (a feature of reality) and intrinsically prescriptive (motivating by its very nature) — no other fact has this structure. Epistemologically: how would we come to know it? Not through the five senses; we would need a special moral intuition faculty. Mackie finds both posits too costly given that simpler explanations are available.