Questions: Moral Naturalism: Moral Facts as Natural Facts

Question 1

Moore's open question argument is best understood as showing that:

• A. Moral facts do not exist because all moral claims are expressions of emotion
• B. No matter what natural property is proposed as the reduction of 'good,' it remains a meaningful question whether things with that property are actually good
• C. Science can determine moral facts, but only through very advanced empirical methods
• D. Moral naturalism is self-refuting because naturalists cannot agree on which natural property 'good' reduces to

Answer: (B)

Moore's argument is that for any proposed natural reduction N of 'good' — pleasure, survival, well-being — you can always intelligibly ask 'But is N actually good?' This question feels open and non-trivial in a way that 'Is water actually H₂O?' does not. Moore argued this shows that 'good' cannot be identical with any natural property; if it were, the question would be as empty as asking whether bachelors are unmarried. The argument targets the very possibility of moral reduction, not the existence of moral facts or the precision of science.

Question 2

A moral naturalist who identifies 'right action' with 'action that promotes well-being' is making the same kind of claim as a chemist who identifies 'water' with 'H₂O.' What is the intended parallel?

• A. Both claims are merely linguistic conventions about how to use words, not factual discoveries
• B. Both are identity claims: in each case, the two descriptions pick out the same underlying natural phenomenon
• C. Both claims are defended by the same experimental methods, and both can be verified in a laboratory
• D. Both claims were initially controversial but are now universally accepted as scientific consensus

Answer: (B)

The parallel is metaphysical, not methodological. The chemist's claim is that 'water' and 'H₂O' are not merely synonymous by convention — they refer to the same real thing, discovered through investigation. The naturalist proposes the same structure for ethics: 'right action' and 'promotes well-being' would refer to the same natural property. This is a reduction by identity, not a definitional stipulation. The comparison is powerful because the water-H₂O identity is now uncontroversial — naturalists argue that moral identities could be similarly discoverable and equally real.

Question 3

Moral naturalism is committed to reducing moral facts to the facts of physics or neuroscience specifically.

• T. True
• F. False

Answer: False

False. Moral naturalism requires only that moral properties are *natural* properties — properties investigated by empirical inquiry. But 'natural' is broad: psychological properties, social-functional properties, and biological properties can all count as natural without being reducible to physics or neuroscience. A naturalist who identifies 'good' with 'promotes flourishing' is appealing to a psychological/functional notion of flourishing, not necessarily to brain states or particle physics. The misconception that naturalism must be reductive all the way down to physics misunderstands what the position requires.

Question 4

The is-ought gap (Hume's claim that you cannot derive 'ought' from 'is') is a decisive refutation of moral naturalism.

• T. True
• F. False

Answer: False

False — though it is a serious challenge, not a decisive refutation. Moral naturalists have several responses. One prominent response is that once you establish an identity between a moral property and a natural property — once 'right' just *is* 'promotes well-being' — you can infer moral facts from natural facts just as you can infer temperature facts from facts about molecular motion once you establish that identity. The identity itself bridges the gap. Whether this response succeeds is a live debate, but it shows that the is-ought gap does not trivially refute naturalism without further argument.

Question 5

What is Moore's open question argument, and why does it pose a challenge to moral naturalism specifically (rather than to moral realism generally)?

Model answer: Moore's argument: for any natural property N proposed as the reduction of 'good,' the question 'Is N actually good?' remains meaningful and open — not trivially answered by definition. Compare: 'Is H₂O actually water?' is empty once you know the identity; but 'Is well-being actually good?' still seems like a genuine question. This challenges naturalism specifically because naturalism requires a successful identity between 'good' and some natural property — if any such identity generates an open question, the reduction fails. Moral realism more generally can accept that moral facts are non-natural while still being objective; it is naturalism's reductionist move specifically that the argument targets.

The argument is most damaging if it shows that 'good' cannot be defined by or identified with any natural property — that it is 'sui generis,' a category unto itself. Naturalists respond by questioning whether the intuition is reliable, by proposing more sophisticated identifications, or by arguing the openness reflects ignorance of the identity rather than its absence. The debate between Moore's challenge and naturalist responses is one of the central disputes in contemporary metaethics.