Martin Peterson

A transformative decision rule alters the representation of a decision problem, either by changing the set of alternative acts or the set of states of the world taken into consideration, or by modifying the probability or value assignments. A set of transformative decision rules is order-independent in case the order in which the rules are applied is irrelevant. The main result of this paper is an axiomatic characterization of order-independent transformative decision rules, based on a single axiom. It is shown that the proposed axiomatization resolves a problem observed by Teddy Seidenfeld in a previous axiomatization by Peterson.

It is commonly assumed that preferences are determinate; that is, that an agent who has a preference knows that she has the preference in question and is disposed to act upon it. This paper argues the dubiousness of that assumption. An account of indeterminate preferences in terms of self-predicting subjective probabilities is given, and a decision rule for choices involving indeterminate preferences is proposed. Wolfgang Spohn’s and Isaac Levi ’s arguments against self-predicting probabilities are also considered, in light of Wlodek Rabinowicz’s recent criticism

To consequentialise a moral theory means to account for moral phenomena usually described in nonconsequentialist terms, such as rights, duties, and virtues, in a consequentialist framework. This paper seeks to show that all moral theories can be consequentialised. The paper distinguishes between different interpretations of the consequentialiser’s thesis, and emphasises the need for a cardinal ranking of acts. The paper also offers a new answer as to why consequentialising moral theories is important: This yields crucial methodological insights about how to pursue ethical inquires.

We argue that non-epistemic values, including moral ones, play an important role in the construction and choice of models in science and engineering. Our main claim is that non-epistemic values are not only “secondary values” that become important just in case epistemic values leave some issues open. Our point is, on the contrary, that non-epistemic values are as important as epistemic ones when engineers seek to develop the best model of a process or problem. The upshot is that models are neither value-free, nor depend exclusively on epistemic values or use non-epistemic values as tie-breakers

The debate over the civilian use of nuclear power is highly polarised. We argue that a reasonable response to this deep disagreement is to maintain that advocates of both camps should modify their positions. According to the analysis we propose, nuclear power is neither entirely right nor entirely wrong, but rather right and wrong to some degree. We are aware that this non-binary analysis of nuclear power is controversial from a theoretical point of view. Utilitarians, Kantians, and other moral theorists make sharp, binary distinctions between right and wrong acts. However, an important argument speaking in favour of our non-binary analysis is that it better reflects our considered intuitions about the ethical trade-offs we face in discussions of nuclear power. The aim of this article is to make this argument sharp by explaining how it can be rendered compatible with, and supported by, the Capability Approach, which is quickly becoming one of the most influential frameworks for thinking about human development

According to the canonical formulation of the modal account of luck [e.g. Pritchard (2005)], an event is lucky just when that event occurs in the actual world but not in a wide class of the nearest possible worlds where the relevant conditions for that event are the same as in the actual world. This paper argues, with reference to a novel variety of counterexample, that it is a mistake to focus, when assessing a given event for luckiness, on events distributed over just the nearest possible worlds. More specifically, our objection to the canonical formulation of the modal account of luck reveals that whether an event is lucky depends crucially on events distributed over all possible worlds–viz., across the modal universe. It is shown that an amended modal account of luck which respects this point has the additional virtue of avoiding a notable kind of counterexample to modal accounts of luck proposed by Lackey (2008).

Some philosophers believe that two objects of value can be ‘roughly equal’, or ‘on a par’, or belong to the same ‘clump’ of value in a sense that is fundamentally different from that in which some objects are ‘better than’, ‘worse than’, or ‘equally as good as’ others. This article shows that if two objects are on a par, or belong to the same clump, then an agent accepting a few plausible premises can be exploited in a money-pump. The central premise of the argument is that value is choice-guiding. If one object is more valuable than another, then it is not permitted to choose the less valuable object; and if two objects are equally valuable it is permitted to choose either of them; and if two objects are on a par or belong to the same clump it is also permitted to choose either of them.

This article argues that, contrary to the received view, prioritarianism and egalitarianism are not jointly incompatible theories in normative ethics. By introducing a distinction between weighing and aggregating, the authors show that the seemingly conflicting intuitions underlying prioritarianism and egalitarianism are consistent. The upshot is a combined position, equality-prioritarianism, which takes both prioritarian and egalitarian considerations into account in a technically precise manner. On this view, the moral value of a distribution of well-being is a product of two factors: the sum of all individuals' priority-adjusted well-being, and a measure of the equality of the distribution in question. Some implications of equality-prioritarianism are considered.

The main result of this paper is a formal argument for the principle of maximizing expected utility that does not rely on the law of large numbers. Unlike the well-known arguments by Savage and von Neumann & Morgenstern, this argument does not presuppose the sure-thing principle or the independence axiom. The principal idea is to use the concept of transformative decision rules for decomposing the principle of maximizing expected utility into a sequence of normatively reasonable subrules. It is shown that this procedure provides a resolution of Allais's paradox that cannot be obtained by Savage-style or von Neumann & Morgenstern-style arguments.

Consequentialism, one of the major theories of normative ethics, maintains that the moral rightness of an act is determined solely by the act's consequences and its alternatives. The traditional form of consequentialism is one-dimensional, in that the rightness of an act is a function of a single moral aspect, such as the sum total of wellbeing it produces. In this book Martin Peterson introduces a new type of consequentialist theory: multidimensional consequentialism. According to this theory, an act's moral rightness depends on several separate dimensions, including individual wellbeing, equality and risk. Peterson's novel approach shows that moral views about equality and risk that were previously thought to be mutually incompatible can be rendered compatible, and his precise theoretical discussion helps the reader to understand better the distinction between consequentialist and non-consequentialist theories. His book will interest a wide range of readers in ethics.

This article introduces and explores a distinction between multi-dimensional and one-dimensional consequentialist moral theories. One-dimensional consequentialists believe that an act's deontic status depends on just one aspect of the act, such as the sum total of wellbeing it produces, or the sum total of priority- or equality-adjusted wellbeing. Multi-dimensional consequentialists believe that an act's deontic status depends on more than one aspect. They may, for instance, believe that the sum total of wellbeing produced by an act and the degree to which the wellbeing is equally distributed in the population affect the act's deontic status independently of each other. These two aspects cannot be reduced into any single (composite) aspect. Wellbeing and equality are two separate considerations that cannot be merged into some novel entity that accurately reflects both intuitions. On the multi-dimensional view I defend, such clashes between separate aspects are irresolvable and are best accounted for by claiming that moral rightness and wrongness are non-binary concepts. Some acts are, literally speaking, a little bit right (because they maximise wellbeing) and a little bit wrong (because they do not maximise equality).1

Pure time preference is a preference for something to come at one point in time rather than another merely because of when it occurs in time. In opposition to Sidgwick, Ramsey, Rawls, and Parfit we argue that it is not always irrational to be guided by pure time preferences. We argue that even if the mere difference of location in time is not a rational ground for a preference, time may nevertheless be a normatively neutral ground for a preference, and this makes it plausible to claim that the preference is rationally permitted

You must either save a group of m people or a group of n people. If there are no morally relevant diff erences among the people, which group should you save? is problem is known as the number problem. e recent discussion has focussed on three proposals: (i) Save the greatest number of people, (ii) Toss a fair coin, or (iii) Set up a weighted lottery, in which the probability of saving m people is m / m + n , and the probability of saving n people is n / m + n . is contribution examines a fourth alternative, the mixed solution, according to which both fairness and the total number of people saved count. It is shown that the mixed solution can be defended without assuming the possibility of interpersonal comparisons of value.

In this paper we shed new light on the Argument from Disagreement by putting it to test in a computer simulation. According to this argument widespread and persistent disagreement on ethical issues indicates that our moral opinions are not influenced by any moral facts, either because no such facts exist or because they are epistemically inaccessible or inefficacious for some other reason. Our simulation shows that if our moral opinions were influenced at least a little bit by moral facts, we would quickly have reached consensus, even if our moral opinions were affected by factors such as false authorities, external political shifts, and random processes. Therefore, since no such consensus has been reached, the simulation gives us increased reason to take seriously the Argument from Disagreement. Our conclusion is however not conclusive; the simulation also indicates what assumptions one has to make in order to reject the Argument from Disagreement. The simulation algorithm we use builds on the work of Hegselmann and Krause (J Artif Soc Social Simul 5(3); 2002, J Artif Soc Social Simul 9(3), 2006).

It is a natural assumption in mainstream epistemological theory that ascriptions of knowledge of a proposition p track strength of epistemic position vis-à-vis p. It is equally natural to assume that the strength of one’s epistemic position is maximally high in cases where p concerns a simple analytic truth. For instance, it seems reasonable to suppose that one’s epistemic position vis-à-vis “a cat is a cat” is harder to improve than one’s position vis-à-vis “a cat is on the mat”, and consequently, that the former is at least as unambiguous a case of knowledge as the latter. The current paper, however, presents empirical evidence which challenges this intuitive line of reasoning. Our study on the epistemic intuitions of hundreds of academic philosophers supports the idea that simple and uncontroversial analytic propositions are less likely to qualify as knowledge than empirical ones. We show that our results, though at odds with orthodox theories of knowledge in mainstream epistemology, can be explained in a way consistent with Wittgenstein’s remarks on ‘hinge propositions’ or with Stalnaker’s pragmatics of assertion. We then present and evaluate a number of lines of response mainstream theories of knowledge could appeal to in accommodating our results. Finally, we show how each line of response runs into some prima facie difficulties. Thus, our observed asymmetry between knowing “a cat is a cat” and knowing “a cat is on the mat” presents a puzzle which mainstream epistemology needs to resolve.

It is widely believed that consequentialists are committed to the claim that persons are mere containers for well-being. In this article I challenge this view by proposing a new version of consequentialism, according to which the identities of persons matter. The new theory, two-dimensional prioritarianism, is a natural extension of traditional prioritarianism. Two-dimensional prioritarianism holds that wellbeing matters more for persons who are at a low absolute level than for persons who are at a higher level and that it is worse to be deprived of a given number of units than it is good to gain the same number of units, even if the new distribution is a permutation of the original one. If a fixed amount of well-being is transferred from one person to another and then transferred back again, two-dimensional prioritarianism implies that it would have been better to preserve the status quo

Johansson and Rosenqvist reject our argument for the rational permissibility of pure time preferences. Johansson and Rosenqvist's main objection is that where two options, X and Y, have equal intrinsic value, there will be a reason to be indifferent between X and Y, and therefore a reason to not hold a PTP for X or Y. In this reply, we argue that if two options have equal intrinsic value, it does not follow that you have a reason to be indifferent. Rather, the two equally large intrinsic values cancel each other out, like two equal weights on kitchen scales.

Armchair philosophers have questioned the significance of recent work in experimental philosophy by pointing out that experiments have been conducted on laypeople and undergraduate students. To challenge a practice that relies on expert intuitions, so the armchair objection goes, one needs to demonstrate that expert intuitions rather than those of ordinary people are sensitive to contingent facts such as cultural, linguistic, socio-economic, or educational background. This article does exactly that. Based on two empirical studies on populations of 573 and 203 trained philosophers, respectively, it demonstrates that expert intuitions vary dramatically according to at least one contingent factor, namely, the linguistic background of the expert: philosophers make different intuitive judgments if their native language is English rather than Dutch, German, or Swedish. These findings cast doubt on the common armchair assumption that philosophical theories based on armchair intuitions are valid beyond the linguistic background against which they were developed