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The author identifies and defines the features of traditional utilitarian theories which account for their appeal, demonstrates that no theory which is exclusively act-oriented can have all the properties that ultilitarians have attempted to build into their theories, and develops a new theory co-operative utilitarianism.

Michael J. Zimmerman offers a conceptual analysis of the moral ‘ought’ that focuses on moral decision-making under uncertainty. His central case, originally presented by Frank Jackson, concerns a doctor who must choose among three treatments for a minor ailment. Her evidence suggests that drug B will partially cure her patient, that one of either drug A or C would cure him completely, but that the other drug would kill him. Accepting the intuition that the doctor ought to choose drug B, (...) Zimmerman argues that moral obligation consists in performing the action that is ‘prospectively best,’ that is ‘that which, from the moral point of view, it is most reasonable for the agent to choose’ given the evidence available to her at the time.Zimmerman defends his Prospective View of moral obligation against two main competitors in the long, first chapter of the book. According to the Objective View, a person ought to choose what is, in fact, the best option. The doctor ought to give her patient whichever drug will actually cure him. The fact that the doctor cannot know whether this is drug …. (shrink)

Many philosophers hold that whether an act is overall morally obligatory is an ‘objective’ matter, many that it is a ‘subjective’ matter, and some that it is both. The idea that it is or can be both may seem to promise a helpful answer to the question ‘What ought I to do when I do not know what I ought to do?’ In this article, three broad views are distinguished regarding what it is that obligation essentially concerns: the maximization of (...) actual value, the maximization of expected value, and the perceived maximization of actual value. The first and third views are rejected; the second view is then refined and defended. The unfortunate upshot is that there may be no very helpful answer to the question just mentioned. As to the question posed in the title of the article, the answer unsurprisingly depends on what ‘objective’ and ‘subjective’ are taken to mean. (Published Online November 24 2006). (shrink)

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)

In this paper, I argue that maximizing act-consequentialism (MAC)—the theory that holds that agents ought always to act so as to produce the best available state of affairs—can accommodate both agent-centered options and supererogatory acts. Thus I will show that MAC can accommodate the view that agents often have the moral option of either pursuing their own personal interests or sacrificing those interests for the sake of the impersonal good. And I will show that MAC can accommodate the idea that (...) certain acts are supererogatory in the sense of not being morally required even though they are what the agent has most moral reason to do. These two theses are surprising in themselves, but even more surprising is how I arrive at them. I argue that anyone generally concerned to accommodate, in some coherent fashion, our pre-theoretical moral intuitions at both the normative and meta-ethical levels will have to give a certain account of agent-centered options and supererogatory acts and that this account is the very one that allows for the maximizing act-consequentialist to accommodate both. So my paper will not only be of interest to those concerned with the tenability of consequentialism, but also to anyone interested in giving a coherent account of our pre-theoretical moral intuitions. (shrink)

The relations between rationality and optimization have been widely discussed in the wake of Herbert Simon's work, with the common conclusion that the rationality concept does not imply the optimization principle. The paper is partly concerned with adding evidence for this view, but its main, more challenging objective is to question the converse implication from optimization to rationality, which is accepted even by bounded rationality theorists. We discuss three topics in succession: (1) rationally defensible cyclical choices, (2) the revealed preference (...) theory of optimization, and (3) the infinite regress of optimization. We conclude that (1) and (2) provide evidence only for the weak thesis that rationality does not imply optimization. But (3) is seen to deliver a significant argument for the strong thesis that optimization does not imply rationality. (shrink)

ABSTRACT. The relations between rationality and optimization have been widely discussed in the wake of Herbert Simon’s work, with the common conclusion that the rationality concept does not imply the optimization principle. The paper is partly concerned with adding evidence for this view, but its main, more challenging objective is to question the converse implication from optimization to rationality, which is accepted even by bounded rationality theorists. We discuss three topics in succession: (1) rationally defensible cyclical choices, (2) the revealed (...) preference theory of optimization, and (3) the infinite regress of optimization. We conclude that (1) and (2) provide evidence only for the weak thesis that rationality does not imply optimization. But (3) is seen to deliver a significant argument for the strong thesis that optimization does not imply rationality. (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)

In this paper I propose an approach to decision theory that I call metanormativism, where the key idea is that decision theory should take into account decision-theoretic uncertainty. I don’t attempt to argue in favor of this view, though I briefly offer some motivation for it. Instead, I argue that if the view is correct, it has important implications for the causal versus evidential decision-theory debate. First, it allows us to make rational sense of our seemingly divergent intuitions across the (...) Smoking Lesion and The Psychopath Button cases. Second, it generates strong new arguments for preferring the causal approach to decision-theory over the evidential approach. (shrink)

Some philosophers have recently argued that decision-makers ought to take normative uncertainty into account in their decisionmaking. These philosophers argue that, just as it is plausible that we should maximize expected value under empirical uncertainty, it is plausible that we should maximize expected choice-worthiness under normative uncertainty. However, such an approach faces two serious problems: how to deal with merely ordinal theories, which do not give sense to the idea of magnitudes of choice-worthiness; and how, even when theories do give (...) sense to magnitudes of choice-worthiness, to compare magnitudes of choice-worthiness across different theories. Some critics have suggested that these problems are fatal to the project of developing a normative account of decision-making under normative uncertainty. The primary purpose of this article is to show that this is not the case. To this end, I develop an analogy between decision-making under normative uncertainty and the problem of social choice, and then argue that the Borda Rule provides the best way of making decisions in the face of merely ordinal theories and intertheoretic incomparability. (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)

Pascal’s Wager is simply too good to be true—or better, too good to be sound. There must be something wrong with Pascal’s argument that decision-theoretic reasoning shows that one must (resolve to) believe in God, if one is rational. No surprise, then, that critics of the argument are easily found, or that they have attacked it on many fronts. For Pascal has given them no dearth of targets.

Pascal’s Wager is simply too good to be true—or better, too good to be sound. There must be something wrong with Pascal’s argument that decision-theoretic reasoning shows that one must believe in God, if one is rational. No surprise, then, that critics of the argument are easily found, or that they have attacked it on many fronts. For Pascal has given them no dearth of targets.

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 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)

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)

Many philosophers have become worried about the use of standard real numbers for the probability function that represents an agent's credences. They point out that real numbers can't capture the distinction between certain extremely unlikely events and genuinely impossible ones—they are both represented by credence 0, which violates a principle known as “regularity.” Following Skyrms 1980 and Lewis 1980, they recommend that we should instead use a much richer set of numbers, called the “hyperreals.” This essay argues that this popular (...) view is the result of two mistakes. The first mistake, which this essay calls the “numerical fallacy,” is to assume that a distinction that isn't represented by different numbers isn't represented at all in a mathematical representation. In this case, the essay claims that although the real numbers do not make all relevant distinctions, the full mathematical structure of a probability function does. The second mistake is that the hyperreals make too many distinctions. They have a much more complex structure than credences in ordinary propositions can have, so they make distinctions that don't exist among credences. While they might be useful for generating certain mathematical models, they will not appear in a faithful mathematical representation of credences of ordinary propositions. (shrink)

In this essay, we explore an issue of moral uncertainty: what we are permitted to do when we are unsure about which moral principles are correct. We develop a novel approach to this issue that incorporates important insights from previous work on moral uncertainty, while avoiding some of the difficulties that beset existing alternative approaches. Our approach is based on evaluating and choosing between option sets rather than particular conduct options. We show how our approach is particularly well-suited to address (...) this issue of moral uncertainty with respect to agents that have credence in moral theories that are not fully consequentialist. (shrink)

This paper investigates two puzzles in practical reason and proposes a solution to them. First, sometimes, when we are practically certain that neither of two alternatives is better than or as good as the other with respect to what matters in the choice between them, it nevertheless seems perfectly rational to continue to deliberate, and sometimes the result of that deliberation is a conclusion that one alternative is better, where there is no error in one’s previous judgment. Second, there are (...) striking differences between rational agents – some rational agents have most reason to pursue careers on Wall Street while others have most reason to take up a career in teaching, or scuba diving, or working for political causes. These differences aren’t plausibly explained by ‘passive’ facts about our psychology or their causal interaction with our environment; instead, these facts seem in some sense to ‘express who we are’. But what is this sense? These puzzles disappear if we adopt a novel view about the source of the normativity of reasons – some reasons are given to us and others are reasons in virtue of an act of will. We make certain considerations reasons through an act of will and thus sometimes make it true through an act of agency that we have most reason to do one thing rather than another. (shrink)

I describe in section 1 how cyclical preferences can arise. In section 2, I relate preference to judgments of choiceworthiness and distinguish between two kinds of preference cycles, vicious and benign. In section 3, I run through the standard money pump in order to show, in section 4, how this pump can be stopped by foresight, using backward induction. A new money pump that *cannot* be stopped by foresight is presented in section 5. This pump works even for agents with (...) benign cyclical preferences. What makes it work is persistency on the part of the would-be exploiter. In section 6, I compare this pump to a diachronic Dutch book that can be set up against someone whose probability assignments violate Reflection. Even in this case, the book only works if the bookie is assumed to be persistent. I use this comparison between preference cyclicity and violations of Reflection in order to question whether exploitability must be seen as a proof of irrationality. Finally, in section 7, I consider resolute choice as an alternative to the backward-induction procedure. While a resolute chooser cannot be exploited, I argue that resoluteness is not required by rationality. The argument is based on a suggestion that rationality, when it comes to actions, is a local rather than a global requirement. (shrink)

There is a debate in normative ethics about whether or not our moral obligations depend solely on either our evidence concerning, or our beliefs about, the world. Subjectivists maintain that they do and objectivists maintain that they do not. I shall offer some arguments in support of objectivism and respond to the strongest argument for subjectivism. I shall also briefly consider the significance of my discussion to the debate over whether one’s future voluntary actions are relevant to one’s current moral (...) obligations. (shrink)

According to John Broome, akrasia consists in a failure to intend to do something that one believes one ought to do, and such akrasia is necessarily irrational. In fact, however, failing to intend something that one believes one ought to do is only guaranteed to be irrational if one is certain of a maximally detailed proposition about what one ought to do; if one is uncertain about any part of the full story about what one ought to do, it could (...) be perfectly rational not to intend to do something that one believes one ought to do. This paper seeks to remedy this problem, by proposing an anti-akrasia principle that covers cases of uncertainty (as well as cases of such complete certainty). It is argued that this principle is in effect the fundamental principle of practical rationality. (shrink)