A major focus of ethical argumentation is determining the relative merits of proposed ethical systems. Nevertheless, even the demonstration that a given ethical system was the one most likely to be correct would not establish that an agent should act in accord with that system. Consider, for example, a situation in which the ethical system most likely to be valid is modestly supportive of a certain action, whereas a less plausible system strongly condemns the same action. Should the agent perform (...) the action, arguing that the most plausible system supports doing so, or avoid the action, being conservative about the strong condemnation of it from a less plausible system? I argue that, in general, different ethical frameworks see the ethical world in fundamentally different ways, rendering the comparison of degrees of support and opposition of actions between systems intrinsically invalid. One should indeed choose to act in accord with the most defensible system. I believe that this important topic needs more attention than it has gotten to date. (shrink)

Representation theorems are often taken to provide the foundations for decision theory. First, they are taken to characterize degrees of belief and utilities. Second, they are taken to justify two fundamental rules of rationality: that we should have probabilistic degrees of belief and that we should act as expected utility maximizers. We argue that representation theorems cannot serve either of these foundational purposes, and that recent attempts to defend the foundational importance of representation theorems are unsuccessful. As a result, we (...) should reject these claims, and lay the foundations of decision theory on firmer ground. (shrink)

We are often uncertain how to behave morally in complex situations. In this controversial study, Ted Lockhart contends that moral philosophy has failed to address how we make such moral decisions. Adapting decision theory to the task of decision-making under moral uncertainly, he proposes that we should not always act how we feel we ought to act, and that sometimes we should act against what we feel to be morally right. Lockhart also discusses abortion extensively and proposes new ways to (...) deal with the ethical and moral issues which surround it. (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)

We typically have to act under uncertainty. We can be uncertain about the relevant descriptive facts, but also about the relevant normative facts. However, the search for a theory of decision-making under normative uncertainty is doomed to failure. First, the most natural proposal for what to do given normative uncertainty faces two devastating problems. Second, the motivations for wanting a theory of what to do given descriptive uncertainty do not carry over to normative uncertainty. Descriptive facts may be inaccessible even (...) in principle, and ignorance of them excuses one from blame, but normative facts are in principle accessible, and ignorance of them arguably is no excuse. Normative facts differ from descriptive facts: normative facts affect what we ought to do no matter what, while descriptive facts affect what we ought to do only insofar as we are aware of them. (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)

This is the classic work upon which modern-day game theory is based. What began as a modest proposal that a mathematician and an economist write a short paper together blossomed, when Princeton University Press published Theory of Games and Economic Behavior. In it, John von Neumann and Oskar Morgenstern conceived a groundbreaking mathematical theory of economic and social organization, based on a theory of games of strategy. Not only would this revolutionize economics, but the entirely new field of scientific inquiry (...) it yielded--game theory--has since been widely used to analyze a host of real-world phenomena from arms races to optimal policy choices of presidential candidates, from vaccination policy to major league baseball salary negotiations. And it is today established throughout both the social sciences and a wide range of other sciences. (shrink)

In the growing literature on decision-making under moral uncertainty, a number of skeptics have argued that there is an insuperable barrier to rational "hedging" for the risk of moral error, namely the apparent incomparability of moral reasons given by rival theories like Kantianism and utilitarianism. Various general theories of intertheoretic value comparison have been proposed to meet this objection, but each suffers from apparently fatal flaws. In this paper, I propose a more modest approach that aims to identify classes of (...) moral theories that share common principles strong enough to establish bases for intertheoretic comparison. I show that, contra the claims of skeptics, there are often rationally perspicuous grounds for precise, quantitative value comparisons within such classes. In light of this fact, I argue, the existence of some apparent incomparabilities between widely divergent moral theories cannot serve as a general argument against hedging for one's moral uncertainties. (shrink)

How should an agent decide what to do when she is uncertain not just about morally relevant empirical matters, like the consequences of some course of action, but about the basic principles of morality itself? This question has only recently been taken up in a systematic way by philosophers. Advocates of moral hedging claim that an agent should weigh the reasons put forward by each moral theory in which she has positive credence, considering both the likelihood that that theory is (...) true and the strength of the reasons it posits. The view that it is sometimes rational to hedge for one's moral uncertainties, however, has recently come under attack both from those who believe that an agent should always be guided by the dictates of the single moral theory she deems most probable and from those who believe that an agent's moral beliefs are simply irrelevant to what she ought to do. Among the many objections to hedging that have been pressed in the recent literature is the worry that there is no non-arbitrary way of making the intertheoretic comparisons of moral value necessary to aggregate the value assignments of rival moral theories into a single ranking of an agent's options. -/- This dissertation has two principal objectives: First, I argue that, contra these recent objections, an agent's moral beliefs and uncertainties are relevant to what she rationally ought to do, and more particularly, that agents are at least sometimes rationally required to hedge for their moral uncertainties. My principal argument for these claims appeals to the enkratic conception of rationality, according to which the requirements of practical rationality derive from an agent's beliefs about the objective, desire-independent value or choiceworthiness of her options. Second, I outline a new general theory of rational choice under moral uncertainty. Central to this theory is the idea of content-based aggregation, that the principles according to which an agent should compare and aggregate rival moral theories are grounded in the content of those theories themselves, including not only their value assignments but also the metaethical and other non-surface-level propositions that underlie, justify, or explain those value assignments. (shrink)

This paper takes on several distinct but related tasks. First, I present and discuss what I will call the “Ignorance Thesis,” which states that whenever an agent acts from ignorance, whether factual or moral, she is culpable for the act only if she is culpable for the ignorance from which she acts. Second, I offer a counterexample to the Ignorance Thesis, an example that applies most directly to the part I call the “Moral Ignorance Thesis.” Third, I argue for a (...) principle—Don’t Know, Don’t Kill—that supports the view that the purported counterexample actually is a counterexample. Finally, I suggest that my arguments in this direction can supply a novel sort of argument against many instances of killing and eating certain sorts of animals. (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)

Nobody's going to object to the advice "Do the right thing", but that doesn't mean everyone's always going to follow it. Sometimes this is because of our volitional limitations; we cannot always bring ourselves to make the sacrifices that right action requires. But sometimes this is because of our cognitive limitations; we cannot always be sure of what is right. Sometimes we can't be sure of what's right because we don't know the non-normative facts. But sometimes, even if we were (...) to know all of the non-normative facts, we'd still not be sure about what's right, because we're uncertain about the normative reasons those facts give us. In this dissertation, I attempt to answer the question of what we're to do when we must act under fundamentally normative uncertainty. It's tempting to think that, in such circumstances, we should do what we regard as most probably right. I argue that this view is mistaken, for it is insensitive to how degrees of actions' values compare across different normative hypotheses; if an action is probably right, but, if wrong, is terribly, terribly, wrong, it may be rational not to do that action. A better answer is that we should do the action with the highest expected value. I spend the first part of the dissertation providing arguments for and rebutting arguments against this view of action under normative uncertainty. I spend the next part of the dissertation explaining what degrees of value are, and showing how they can be compared across normative hypotheses. In the remaining parts of the dissertation, I consider two questions related to our primary question -- first, what is one required, or obligated, to do under normative uncertainty; and second, what is it rational for one to do when one is not only normatively uncertain in the way we've been discussing, but also uncertain about what it is rational to do under this sort of normative uncertainty. (shrink)

Esteemed philosopher John Broome avoids the familiar ideological stances on climate change policy and examines the issue through an invigorating new lens. As he considers the moral dimensions of climate change, he reasons clearly through what universal standards of goodness and justice require of us, both as citizens and as governments. His conclusions—some as demanding as they are logical—will challenge and enlighten. Eco-conscious readers may be surprised to hear they have a duty to offset all their carbon emissions, while policy (...) makers will grapple with Broome’s analysis of what if anything is owed to future generations. From the science of greenhouse gases to the intricate logic of cap and trade, Broome reveals how the principles that underlie everyday decision making also provide simple and effective ideas for confronting climate change. Climate Matters is an essential contribution to one of the paramount issues of our time. (shrink)

This study uses techniques from economics to illuminate fundamental questions in ethics, particularly in the foundations of utilitarianism. Topics considered include the nature of teleological ethics, the foundations of decision theory, the value of equality and the moral significance of a person's continuing identity through time.

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)

This note is a generalization and improved interpretation of the main result of Karni and Schmeidler. A decision-maker is supposed to possess a preference relation on acts and another preference relation on state-prize lotteries, both of which are assumed to satisfy the von Neumann–Morgenstern axioms. In addition, the two preference relations restricted to a state of nature are assumed to agree. We show that these axioms are necessary and sufficient for the existence of subjective expected utility over acts with state-dependent (...) utility functions and a subjective probability measure. This subjective probability measure is unique when conditioned on the set of states of nature in which not all the prizes are equally desirable. (shrink)