The Desire-as-Belief thesis (DAB) states that any rational person desires a proposition exactly to the degree that she believes or expects the proposition to be good. Many people take David Lewis to have shown the thesis to be inconsistent with Bayesian decision theory. However, as we show, Lewis's argument was based on an Invariance condition that itself is inconsistent with the (standard formulation of the) version of Bayesian decision theory that he assumed in his arguments against DAB. The aim of (...) this paper is to explore what impact the rejection of Invariance has on the DAB thesis. Without assuming Invariance, we first refute all versions of DAB that entail that there are only two levels of goodness. We next consider two theses according to which rational desires are intimately connected to expectations of (multi-levelled) goodness, and show that these are consistent with Bayesian decision theory as long as we assume that the contents of 'value propositions' are not fixed. We explain why this conclusion is independently plausible, and show how to construct such propositions. (shrink)

One of the principles on how to act under moral uncertainty, My Favourite Theory, says roughly that a morally conscientious agent chooses an option that is permitted by the most credible moral theory. In defence of this principle, we argue that it prescribes consistent choices over time, without relying on intertheoretic comparisons of value, while its main rivals are either plagued by moral analogues of money pumps or in need of a method for making non-arbitrary intertheoretic comparisons. We rebut the (...) arguments that have been levelled against My Favourite Theory and offer some arguments against intertheoretic comparisons of value. (shrink)

Many believe that we ought to save a large number from being permanently bedridden rather than save one from death. Many also believe that we ought to save one from death rather than a multitude from a very minor harm, no matter how large this multitude. I argue that a principle I call “Aggregate Relevant Claims” satisfactorily explains these judgments. I offer a rationale for this principle and defend it against objections.

The combination of this vindication of moral deference and diagnosis of its fishiness nicely accommodates, I argue, some related phenomena, like the (neglected) fact that our uneasiness with moral deference is actually a particular instance of uneasiness with opaque evidence in general when it comes to morality, and the (familiar) fact that the scope of this uneasiness is wider than the moral as it includes other normative domains.

I defend normative externalism from the objection that it cannot account for the wrongfulness of moral recklessness. The defence is fairly simple—there is no wrong of moral recklessness. There is an intuitive argument by analogy that there should be a wrong of moral recklessness, and the bulk of the paper consists of a response to this analogy. A central part of my response is that if people were motivated to avoid moral recklessness, they would have to have an unpleasant sort (...) of motivation, what Michael Smith calls “moral fetishism”. (shrink)

One of the perennial challenges of ethical theory has been to provide an answer to a number of views that appear to undermine the importance of ethical questions. We may refer to such views collectively as “deflationary ethical theories.” These include theories, such as nihilism, according to which no action is better than any other, as well as relativistic theories according to which no ethical theory is better than any other. In this article I present a new response to such (...) deflationary ethical views. Drawing a distinction between acceptance and rejection, on the one hand, and belief and disbelief, on the other, I argue that we have strong reason to reject these theories, even if we do not have reason to disbelieve them. In Section I, I clarify the question of what ethical theory we should accept, and I argue for the central importance of this question. In Section II, I discuss what I call “absolutely deflationary” ethical theories. These are theories according to which it matters not at all what we do or not at all what ethical theory we accept. I argue that it is generally rational to reject any theory of this kind. In Section III, I discuss what I call “relatively deflationary” ethical theories. These are theories according to which it matters little what we do or what ethical theory we accept. I argue that we have strong pro tanto reason to reject theories of this kind. And then, in Sections IV and V, I reply to some common objections to my arguments. Throughout, I will be arguing not that deflationary ethical theories are false but only that we should reject them from the practical point of view as a basis for guiding our actions. (shrink)

Argues for the humean theory of motivation on the grounds that rejecting it requires rejecting decision theory.

How ought you to evaluate your options if you're uncertain about what's fundamentally valuable? A prominent response is Expected Value Maximisation (EVM)—the view that under axiological uncertainty, an option is better than another if and only if it has the greater expected value across axiologies. But the expected value of an option depends on quantitative probability and value facts, and in particular on value comparisons across axiologies. We need to explain what it is for such facts to hold. Also, EVM (...) is by no means self-evident. We need an argument to defend that it’s true. This book introduces an axiomatic approach to answer these worries. It provides an explication of what EVM means by use of representation theorems: intertheoretic comparisons can be understood in terms of facts about which options are better than which, and mutatis mutandis for intratheoretic comparisons and axiological probabilities. And it provides a systematic argument to the effect that EVM is true: the theory can be vindicated through simple axioms. The result is a formally cogent and philosophically compelling extension of standard decision theory, and original take on the problem of axiological or normative uncertainty. (shrink)

According to ‘Excluders’, descriptive uncertainty – but not normative uncertainty – matters to what we ought to do. Recently, several authors have argued that those wishing to treat normative uncertainty differently from descriptive uncertainty face a dependence problem because one's descriptive uncertainty can depend on one's normative uncertainty. The aim of this paper is to determine whether the phenomenon of dependence poses a decisive problem for Excluders. I argue that existing arguments fail to show this, and that, while stronger ones (...) can be found, Excluders can escape them. (shrink)

Most non-consequentialists “let the numbers count” when one can save either a lesser or greater number from equal or similar harm. But they are wary of doing so when one can save either a small number from grave harm or instead a very large number from minor harm. Limited aggregation is an approach that reconciles these two commitments. It is motivated by a powerful idea: our decision whom to save should respect each person who has a claim to our help, (...) including those whom we fail to save. However, it has recently been argued that it is open to decisive objections. I develop a new limitedly aggregative view:Hybrid Balance Relevant Claims. This view is well grounded in the reasons we have to be skeptical of aggregation and resolves all recent challenges by paying careful attention to the rationale for limited aggregation. (shrink)

While ordinary decision theory focuses on empirical uncertainty, real decision-makers also face normative uncertainty: uncertainty about value itself. From a purely formal perspective, normative uncertainty is comparable to (Harsanyian or Rawlsian) identity uncertainty in the 'original position', where one's future values are unknown. A comprehensive decision theory must address twofold uncertainty -- normative and empirical. We present a simple model of twofold uncertainty, and show that the most popular decision principle -- maximising expected value (`Expectationalism') -- has different formulations, namely (...) Ex-Ante Expectationalism, Ex-Post Expectationalism, and hybrid theories. These alternative theories recommend different decisions, reasoning modes, and attitudes to risk. But they converge under an interesting (necessary and sufficient) condition. (shrink)

In this paper, I enter the debate between those who hold that our normative uncertainty matters for what we ought to do, and those who hold that only our descriptive uncertainty matters. I argue that existing views in both camps have unacceptable implications in cases where our descriptive beliefs depend on our normative beliefs. I go on to propose a fix which is available only to those who hold that normative uncertainty matters, ultimately leaving the challenge as a threat to (...) recent skepticism about such views. (shrink)

On Hume’s account of motivation, beliefs and desires are very different kinds of propositional attitudes. Beliefs are cognitive attitudes, desires emotive ones. An agent’s belief in a proposition captures the weight he or she assigns to this proposition in his or her cognitive representation of the world. An agent’s desire for a proposition captures the degree to which he or she prefers its truth, motivating him or her to act accordingly. Although beliefs and desires are sometimes entangled, they play very (...) different roles in rational agency. In two classic papers (Lewis 1988, 1996), David Lewis discusses several challenges to this Humean picture, but ultimately rejects them. We think that his discussion of a central anti-Humean alternative – the desire-as-belief thesis – is in need of refinnement. On this thesis, the desire for proposition p is given by the belief that p is desirable. Lewis claims that ‘[e]xcept in trivial cases, [this thesis] collapses into contradiction’(Lewis 1996, p. 308). The problem, he argues, is that the thesis is inconsistent with the purportedly plausible requirement that one’s desire for a proposition should not change upon learning that the proposition is true; call this the invariance requirement. In this paper, we revisit Lewis’s argument. We show that, if one carefully distinguishes between non-evaluative and evaluative propositions, the desire-asbelief thesis can be rendered consistent with the invariance requirement. Lewis’s conclusion holds only under certain conditions: the desire-as-belief thesis conflicts with the invariance requirement if and only if there are certain correlations between non-evaluative and evaluative propositions. But when there are such correlations, we suggest, the invariance requirement loses its plausibility. Thus Lewis’s argument against the desire-as-belief thesis appears to be valid only in cases in which it is unsound. (shrink)

How ought you to evaluate your options if you’re uncertain about which axiology is true? One prominent response is Expected Moral Value Maximisation, the view that under axiological uncertainty, an option is better than another if and only if it has the greater expected moral value across axiologies. EMVM raises two fundamental questions. First, there’s a question about what it should even mean. In particular, it presupposes that we can compare moral value across axiologies. So to even understand EMVM, we (...) need to explain what it is for such comparisons to hold. Second, assuming that we understand it, there’s a question about whether EMVM is true. Since there are many plausible rivals, we need an argument to defend it. In this paper, I’ll introduce a representation theorem for axiological uncertainty to answer these two questions. Roughly, the theorem shows that if all our axiologies satisfy the von Neumann–Morgenstern axioms, and if the facts about which options are better than which in light of your uncertainty also satisfy these axioms as well as a Pareto condition, then these facts have a relevantly unique expected utility representation. If I’m right, this theorem at once affords us a compelling way to understand EMVM—and specifically intertheoretic comparisons—and a systematic argument for its truth. (shrink)

In “Rejecting Ethical Deflationism,” Jacob Ross argues that a rational decision maker is permitted, for the purposes of practical reasoning, to assume that nihilism is false. I argue that Ross’s argument fails because the principle he relies on conflicts with more plausible principles of rationality and leads to preference cycles. I then show how the infectiousness of nihilism, and of incomparability more generally, poses a serious problem for the larger project of attempting to incorporate moral uncertainty into expected value maximization (...) style reasoning. (shrink)

A popular model of normative decision-making under uncertainty suggests choosing the option with the maximum expected moral choice-worthiness (MEC), where the choice-worthiness values from each moral theory, which are assumed commensurable, are weighted by credence and combined. This study adds descriptive uncertainty about the non-moral facts of a situation into the model by treating choice-worthiness as a random variable. When agents face greater descriptive uncertainty, the choice-worthiness random variable will have a greater spread and a larger standard deviation. MEC, as (...) a decision rule, is sensitive only to the expected value of the random variable and not to its standard deviation. For example, MEC is insensitive to cases where an option with a large degree of descriptive uncertainty may have a higher probability of being below some threshold of impermissibility than does an option with less dispersion, even though the latter has a higher expected choice-worthiness. When applied to the same situation, similar moral theories will have statistically correlated choice-worthiness values. This correlation affects the dispersion of the credence-weighted sum of the random variables but not its expected value. Thus, MEC is insensitive to aspects of the normative situation to which a good decision-rule should be sensitive. (shrink)

It has been argued by several philosophers that a morally motivated rational agent who has to make decisions under conditions of moral uncertainty ought to maximize expected moral value in his choices, where the expectation is calculated relative to the agent's moral uncertainty. I present a counter-example to this thesis and to a larger family of decision rules for choice under conditions of moral uncertainty. Based on this counter-example, I argue against the thesis and suggest a reason for its failure (...) – that it is based on the false assumption that inter-theoretical comparisons of moral value are meaningful. (shrink)

Morally speaking, what should one do when one is morally uncertain? Call this the Moral Uncertainty Question. In this paper, I argue that a non-ideal moral theory provides the best answer to the Moral Uncertainty Question. I begin by arguing for a strong ought-implies-can principle---morally ought implies agentially can---and use that principle to clarify the structure of a compelling non-ideal moral theory. I then describe the ways in which one's moral uncertainty affects one's moral prescriptions: moral uncertainty constrains the set (...) of moral prescriptions one is subject to, and at the same time generates new non-ideal moral reasons for action. I end by surveying the problems that plague alternative answers to the Moral Uncertainty Question, and show that my preferred answer avoids most of those problems. (shrink)

Suppose you believe you’re morally required to φ‎ but that it’s not a big deal; and yet you think it might be deeply morally wrong to φ‎. You are in a state of moral uncertainty, holding high credence in one moral view of your situation, while having a small credence in a radically opposing moral view. A natural thought is that in such a case you should not φ‎, because φ‎ing would be too morally risky. The author argues that this (...) natural thought is misguided. If φ‎ing is in fact morally required, then you should φ‎, and this is so even taking into account your moral uncertainty. The author argues that if the natural thought were correct, then being caught in the grip of a false moral view would be exculpatory: people who do morally wrong things thinking they are acting morally rightly would be blameless. But being caught in the grip of a false moral view is not exculpatory. So the natural thought is false. The author develops the claim that you should act as morality actually requires as a candidate answer to the question “how should one act in the face of moral uncertainty?” This answer has been dismissed in discussion up to this point. The author argues that not only is this answer a serious contender; it is the correct answer. (shrink)

This paper argues in favor of a particular account of decision‐making under normative uncertainty: that, when it is possible to do so, one should maximize expected choice‐worthiness. Though this position has been often suggested in the literature and is often taken to be the ‘default’ view, it has so far received little in the way of positive argument in its favor. After dealing with some preliminaries and giving the basic motivation for taking normative uncertainty into account in our decision‐making, we (...) consider and provide new arguments against two rival accounts that have been offered—the accounts that we call ‘My Favorite Theory’ and ‘My Favorite Option’. We then give a novel argument for comparativism—the view that, under normative uncertainty, one should take into account both probabilities of different theories and magnitudes of choice‐worthiness. Finally, we further argue in favor of maximizing expected choice‐worthiness and consider and respond to five objections. (shrink)