the subjective ‘ought’ and the three-envelope problem
Suppose Margaret is put in the following choice-situation. She is placed in front of three envelopes. She is told that she will be allowed to choose one envelope. She is also told that there is $1500 in either envelope one or envelope two, and that there is $1000 in envelope three. Let’s say that the $1500 is in envelope one. Following Jake Ross, call this the three-envelope problem. Intuitively, Margaret ought to choose envelope three. Unfortunately, this case causes all sorts of trouble for most views about ‘ought’ (Coincidentally, there has been some recent discussion about this type of case on the blogosphere. See here for my, Alex’s, and Richard’s discussion at Richard’s blog; see the comments here for some discussion at Pea Soup).
Many ethicists and epistemologists already think they know the answer. They want to say that there is a distinction to be made between the objective ‘ought’ and the subjective ‘ought’. One objectively ought to 
I’m going to argue here that two popular ways of formulating the subjective ‘ought’ cannot give an adequate explanation of why Margaret ought to choose envelope three.
Let’s begin by discussing what (Jake) Ross calls objective reductionism about ought. On this view, subjective ‘ought’ is defined in terms of the objective ‘ought’. Subjective-O1 is a rough characterization of the view:
subjective-o1: Necessarily, A subjectively ought to
iff A would be objectively obligated to
Parfit holds a view similar to this (the differences don’t matter for my argument). Unfortunately, this view doesn’t conclude that Margaret subjectively ought to choose envelope three. That’s because if her beliefs were true, then she would be objectively obligated to choose either one or two. In other words, suppose her belief that the $1500 is either in envelope one or envelope two is true. Then the $1500 is either in envelope one, in which case she objectively ought to choose envelope one, or it is in envelope two, in which case she objectively ought to choose envelope two. This view, then, cannot explain why Margaret subjectively ought to choose envelope three.
Mark Schroeder defends a view that is in some ways quite similar to Parfit’s view, but is in many ways much better. He defends what we’ll call objective reductionism about reasons. This view builds subjective reasons out of objective reasons. It then defines subjective oughts in terms of subjective reasons. Subjective-R is a rough definition of subjective reason:
subjective-r: A has a subjective reason R to
The subjective ‘ought’ is then defined in terms of subjective reasons. Subjective-O2 is the definition of the subjective ought on this view.
subjective-o2: Necessarily, A subjectively ought to
This view can explain why Margaret subjectively ought to choose envelope three. That’s because on this view what one subjectively ought to do is determined by the weight of one’s subjective reasons, not by the weight of one’s objective reasons. The subjective reasons that are relevant are that there is a .5 chance that $1500 is in envelope one and that there is a .5 chance that there is $1500 in envelope two and that there is $1000 in envelope three. Plausibly, the weight of the third subjective reason is decisive. Thus, on this view, Margaret subjectively ought to choose envelope three (when she has the relevant beliefs).
But I don’t think this is captures why we think Margaret ought to choose envelope three. To see this, imagine that Margaret carelessly listens to what she is told. She thus believes that the $1500 is in either envelope one or envelope three, and that the $1000 is in envelope two. On objective reductionism about reasons, Margaret subjectively ought to choose envelope two. But, I still have the intuition that even if this is true, there is still some sense in which Margaret ought to choose envelope three. Carelessness is not a way to dodge that obligation.
Of course, there are countless other ways in which Margaret could turn out not to be subjectively obligated to choose envelope three on this proposal. She could simply fail to believe anything at all about the envelopes. In all of these cases I still think she ought to choose envelope three. If this is right, then there is something fundamentally misguided about trying to explain why Margaret ought to choose envelope three by appealing to this type of subjective ought. I want to suggest that what is misguided is forging such a tight link between what the agent ought to do and what the agent believes. What is really driving our intuitions is that the information is available. In other words, what determines what Margaret ought to do in the sense we are after is the information state she is in. Any view that attempts to explain why Margaret ought to choose envelope three that doesn’t take this into account is doomed to be unintuitive.
I have a positive account to offer, but that will have to wait for another day.
Hey Errol,
I like the case, the three envelope example seems a lot like the mineshaft case as both seem to show that subjective-01 doesn’t really characterize any interesting notion of ‘ought’. I think that the point you make about the relation between the subjective ‘ought’ and the information available, but isn’t it typical for people who relativize an ‘ought’ to the subject’s beliefs typically relativize them to reasonable beliefs? It seems this might cover reasonable suspensions of judgment, too.
Anyway, suppose you and I are watching Margaret and we know where the most money is. Margaret picks an envelope. I say, “You should have picked envelope two, but since you couldn’t have known that, you should have picked envelope three”. What this says (roughly) is that while she should have picked envelope two, she could not have known how to do that, so the best we could hope for is that she’d cut her losses and pick three.
Clayton,
I don’t know of anyone who relativizes only to justified beliefs. Parfit argues against this view at length. And I think for good reason, since relativizing to justified beliefs seems to undercut the initial rationale for relativizing to beliefs in the first place. The standard rationale is that what matters rationally is forming new attitudes that cohere with the attitudes one already has. That’s why Parfit argues that what is important with respect to rationality isn’t the justificatory status of one’s beliefs, it’s the contents of those beliefs. Obviously, relativizing to justified beliefs undermines this rationale. Moreover, I still don’t think it will work. For suppose there is propositional justification for believing that there is $1000 in envelope three, but Margaret simply doesn’t believe it. I still think that she ought to choose envelope three. That said, I think the view that holds that rationality supervenes on the propositions that are propositionally justified given one’s epistemic position is one of two views that might be correct. It’s not, however, the view I prefer.
Anyway, suppose you and I are watching Margaret and we know where the most money is. Margaret picks an envelope. I say, “You should have picked envelope two, but since you couldn’t have known that, you should have picked envelope three”.
Part of the positive things that I want to argue for w.r.t. ought is that ought is assessor-sensitive. So, my view holds that if we are watching Margaret and we know where the money is, the proposition Margaret ought to choose envelope three is false. But the view also can say that from Margaret’s context of assessment that proposition is true. I don’t feel the pull of your paraphrase much at all. I have the strong intuition that really and truly, what Margaret ought to do is choose envelope three. Since ought is assessment-sensitive on my view, I can still say that from our perspective what Margaret really and truly ought to do is choose envelope one.
think the view that holds that rationality supervenes on the propositions that are propositionally justified given one’s epistemic position is one of two views that might be correct.
That’s the sort of view I had in mind. It’s relativized to justifiers, as it were, rather than the justified.
I’ll wait and see what the assessor relative account looks like, I’m not sure I see how the view is supposed to work. There’s two observations that I take it we want an account to account for. First, that there’s a perfectly good sense in which we think/say ‘Margaret ought to pick 3′. Second, that those with insider’s information can say/think ‘Margaret ought to pick 1′. On the assessor relative view, how do you account for this? Do you try to explain away one or the other observations? On the sort of view I favor (but haven’t really developed in any sort of detail), there is one use of ‘ought’ that is supposed to convey the idea that something is the best we could have hoped for given someone’s information, but it’s not really what the person ought to do (not necessarily, at any rate).
Clayton,
The assessor-relativity of my view is meant to be able to (1) account for the fact that ‘Margaret ought to pick three’ is true in Margaret’s context of assessment and false in the insider’s context of assessment and (2) account for the sense in which Margaret and the insider’s judgments are in conflict. Since truth-values are relativized to, inter alia, contexts of assessment, my view can explain (1). But since my view is non-indexical, it can still hold that the insiders are denying the proposition that Margaret is asserting.
[...] objective ‘ought’ and the three-envelope problem We left off with the failure of two state of the art views about the subjective ought to explain why Margaret [...]
the objective ‘ought’ and the three-envelope problem « The Excluded Middle said this on August 3, 2008 at 5:18 pm |