Sunday, April 05, 2009

Parfit's Triviality Objection

Meta-ethical naturalists hold that normative claims, e.g. 'You ought to phi', state purely natural facts, e.g. phi-ing would maximize happiness. Parfit objects that, unless we distinguish right-making features from rightness itself, our first-order normative ethical theories will be rendered trivial.

Suppose we're utilitarians. So we accept the following principle:

(U) an act is right just in case it would maximize happiness.

A non-naturalist utilitarian may make the substantive claim that whenever an act has the natural property of maximizing happiness, it thereby has the further (irreducibly normative) property of being right. If a naturalist collapses these, then their assertion of (U) seems less substantive. They are simply asserting the fact that whenever an act has the natural property of maximizing happiness, it has this very property. But that's trivial.

A complication: examples like (E) 'molecular kinetic energy is the same as heat' show us that metaphysically 'trivial' identity statements can nonetheless be informative or cognitively significant. This may be so if, although both sides of the identity statement refer to one and the same property, they refer to it in different ways (or by way of different reference-fixing descriptions). For then, in addition to the explicitly stated trivial fact, we may learn an implicitly stated substantive fact. Parfit explains:

This claim [E] gives us important information because the concept of heat is the concept of the property that is related in certain ways to certain other, different properties. (E) can be restated here as:

(F) having molecular kinetic energy is the property that can make an object have the different properties of being able to melt solids, turn liquids into gases, cause certain sensations, etc.

Here is the challenge for the metaethical naturalist: they must explain what substantive natural fact is implicitly conveyed by the likes of (U), to make such moral claims informative.

Parfit doesn't think this challenge can be met. But why not? I would have thought the obvious response for a naturalist is to adopt a kind of moral functionalism (a la Frank Jackson). The reference of 'ought' is fixed by its conceptual role R in our cognitive economy. Then, when the naturalist utilitarian claims that we ought to maximize happiness, they are implicitly conveying the substantive fact that the property of maximizing happiness has the (further) property of being such as to fulfill role R.

The problem is made vivid in Parfit's example of the naturalist utilitarian who horrifies the hospital Ethics Committee by endorsing the surreptitious murder of a patient for purpose of stealing their organs and saving more lives on net. Parfit imagines the naturalist responding as follows:
When I claimed that I ought to kill this patient, I was claiming only that this act would maximize happiness. I was not claiming that this act would have the different property of being what I ought to do. On my view, there is no such different property. Being an act that would maximize happiness is the same as being what we ought to do. Since I was claiming only that killing this patient would maximize happiness, no one has any reason to reject my claim.

But this does not seem to capture how naturalists tend to understand their own view. (The imagined 'distancing' of oneself from the ordinary understanding of moral commitments seems especially inapposite.) When naturalists make first-order claims about which natural features are right-making features, they are not only claiming that these features are self-identical (though that may be the explicit content or truthmaker for their claim, just as when scientists claim that heat is molecular energy). Rather, they are conveying the additional, important information that this feature is what the rest of us are ultimately referring to with our ordinary moral talk. That is: maximizing happiness (or whatever) is the natural property that is ultimately picked out by the reference-fixing descriptions R associated with the normative terms 'right', 'ought', etc.

There are other objections that could be made at this point, e.g. concerning whether the naturalist can really capture the full normative force of these claims. But I think the triviality objection fails.

Update: It turns out I was a bit quick in dismissing this argument.  Parfit appeals to the premise that a claim like (U) is not merely informative, but more specifically that it is a positive substantive normative claim, which attributes a distinct normative property to acts that have the property of maximizing happiness (or whatever).  It's much less clear whether the naturalist can meet this demand, since the "further information" they take us to be implicitly attributing seems to be more sociological or linguistic in nature, rather than attributing any further normative property.


  1. Yeah, that's how I'm inclined to respond, but you put it better than I could have. I haven't read the manuscript, but I would be surprised if Parfit did not consider this Canberra Plan response.

    Just a very minor point (that's beside the point, so you can ignore it): "A ought to X" is perhaps materially equivalent to "X-ing is the right thing to do (for A)". But they do not have the same logical form. The first statement implies that A can fail to X, and the second statement need not carry that implication. So I'm a bit bothered when philosophers use those two statements interchangeably.

  2. I agree that the sort of functionalism defended by Jackson, Smith, Lewis and others provides an adequate answer to Parfit's triviality objection. It seems to me that this objection is tenable only if restricted to the non-functionalist form of naturalism defended by Boyd, Sturgeon, Railton, and Brink.

  3. One minor point: in the context of the triviality objection what matters seems to be, not the reference-fixing descriptions of 'ought', 'right', etc, but the cognitive significance of those terms. The discoveries that water is H2O or that heat is molecular energy were non-trivial, I think, because of what we have in mind when we think about 'water' or 'heat', regardless of the way in which the reference of these terms was initially fixed.

  4. (I was assuming that reference is fixed precisely by the description that we 'have in mind'. But if you think these can come apart, I agree it's the latter that matters here.)

  5. This argument of Parfit's has been confusing me since I first saw it. Let me try and say something in its favour.

    I take the issue to be this: The identity statement between heat and kinetic energy is informative because we draw different inferences using the concept of heat than we do using the concept of kinetic energy. That suggests that the identity statement between is right and maximises happiness can also be informative, so long as we draw different inferences using these concepts.

    But now look at the kinds of inferences we draw using the concept of heat that we didn't draw about kinetic energy: about melting solids, causing sensations, and so on. These inferences relate facts about heat to facts that are, in some sense, independent of heat. For example, the idea of a solid turning into a liquid is one a person could have without already having the concept of heat.

    But now compare with rightness. The kinds of inferences that we draw using the concept of rightness are: about reasons, value, obligation, and perhaps motivation, intention, and other related concepts. These inferences relate facts about rightness only to facts that are themselves already dependent on rightness. For example, you could only have the concept of a reason if you already had the concept of rightness.

    Another way to phrase this is that it seems as though normative concepts are insulated (no pun intended) from other concepts in a way that heat concepts are not. When we learnt that heat was kinetic energy, we learnt about how kinetic energy related to facts that do not require understanding of the concept of heat. But if we learn that rightness is happiness maximising, we learn only about how happiness maximising relates to facts that do require understanding of the concept of rightness.

    But I'm really not sure of just how well this disanalogy holds, so perhaps someone can set me straight.

  6. Right, and Parfit does point out that there's a regress problem if we think that the identity statement informs us about other normative facts (reasons, values, obligations). But a moral functionalist may propose that our normative concepts are not so insulated after all. Admittedly, the function role of 'right' is much less obvious than the functional role of 'heat', but at the end of conceptual analysis we would find that it similarly invokes a whole raft of ordinary, natural relations. (I'm not sure how plausible this is, but it's a possible view, at least.)

  7. This is interesting, thanks Richard. I agree with the response (tried to argue for it in pretty similar way a while ago in here:



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