Population Ethics

Population axiology concerns how to evaluate populations in terms of their moral goodness, that is, how to order populations by the relations “is better than” and “is as good as”. The task has been to find an adequate theory about the moral value of states of affairs where the number of people, the quality of their lives, and their identities may vary. So far, this field has largely ignored issues about uncertainty and the conditions that have been discussed mostly pertain (...) to the ranking of risk-free outcomes. Most public policy choices, however, are decisions under uncertainty, including policy choices that affect the size of a population. Here, we shall address the question of how to rank population prospects—that is, alternatives that contain uncertainty as to which population they will bring about—by the relations “is better than” and “is as good as”. We start by illustrating how well-known population axiologies can be extended to population prospect axiologies. And we show that new problems arise when extending population axiologies to prospects. In particular, traditional population axiologies lead to prospect-versions of the problems that they praised for avoiding in the risk-free settings. Finally, we identify an intuitive adequacy condition that, we contend, should be satisfied by any population prospect axiology, and show how given this condition, the impossibility theorems in population axiology can be extended to (non-trivial) impossibility theorems for population prospect axiology. (shrink)

Variable-Value axiologies propose solutions to the challenges of population ethics. These views avoid Parfit's Repugnant Conclusion, while satisfying some weak instances of the Mere Addition principle (for example, at small population sizes). We apply calibration methods to Variable-Value views while assuming: first, some very weak instances of Mere Addition, and, second, some plausible empirical assumptions about the size and welfare of the intertemporal world population. We find that Variable-Value views imply conclusions that should seem repugnant to anyone who opposes Total (...) Utilitarianism due to the Repugnant Conclusion. So, any wish to avoid repugnant conclusions is not a good reason to choose a Variable-Value view. More broadly, these calibrations teach us something about the effort to avoid the Repugnant Conclusion. Our results join a recent literature arguing that prior efforts to avoid the Repugnant Conclusion hinge on inessential features of the formalization of repugnance. Some of this effort may therefore be misplaced. (shrink)

Average utilitarianism and several related axiologies, when paired with the standard expectational theory of decision-making under risk and with reasonable empirical credences, can find their practical prescriptions overwhelmingly determined by the minuscule probability that the agent assigns to solipsism -- i.e., to the hypothesis that there is only one welfare subject in the world, viz., herself. This either (i) constitutes a reductio of these axiologies, (ii) suggests that they require bespoke decision theories, or (iii) furnishes a novel argument for ethical (...) egoism. (shrink)

Is the overall value of a world just the sum of values contributed by each value-bearing entity in that world? Additively separable axiologies (like total utilitarianism, prioritarianism, and critical level views) say 'yes', but non-additive axiologies (like average utilitarianism, rank-discounted utilitarianism, and variable value views) say 'no'. This distinction is practically important: additive axiologies support 'arguments from astronomical scale' which suggest (among other things) that it is overwhelmingly important for humanity to avoid premature extinction and ensure the existence of a (...) large future population, while non-additive axiologies need not. We show, however, that when there is a large enough 'background population' unaffected by our choices, a wide range of non-additive axiologies converge in their implications with some additive axiology -- for instance, average utilitarianism converges to critical-level utilitarianism and various egalitarian theories converge to prioritiarianism. We further argue that real-world background populations may be large enough to make these limit results practically significant. This means that arguments from astronomical scale, and other arguments in practical ethics that seem to presuppose additive separability, may be truth-preserving in practice whether or not we accept additive separability as a basic axiological principle. (shrink)

It has been known for quite a while that traditional ethical theories have very counterintuitive and paradoxical implications for questions concerning procreation and our moral duties to future generations. Classical Utilitarianism, for example, seems to imply that we have a moral duty to procreate and that we should try to have as many off-springs as possible. More disturbingly, it implies Derek Parfit’s well-known Repugnant Conclusion.

Formal arguments have proven that avoiding the Repugnant Conclusion is impossible without rejecting one or more highly plausible population principles. To many, such proofs establish not only a deep challenge for axiology, but also pose an important practical problem of how policymaking can confidently proceed without resolving any of the central questions of population ethics. Here we offer deflationary responses: first to the practical challenge, and then to the more fundamental challenge for axiology. Regarding the practical challenge, we provide an (...) overview of recent literature that explores the implications for public policy of the Repugnant Conclusion and related puzzles within population ethics, and shows that there is more commonality in the implications of different population axiologies than is generally recognized. The upshot is that uncertainty about population ethics presents no important problem for policymaking, and the importance of population ethics to policymaking has been overstated. We then turn to more fundamental issues about axiology, and describe a new series of formal proofs that undermine the idea that any plausible axiology could avoid the Repugnant Conclusion, including those that are assumed to avoid it in the literature. The philosophical upshot is that the Repugnant Conclusion cannot plausibly be avoided, and so it is a mistake to assume as a constraint on a plausible axiology that it must be avoided, as is assumed by most of the literature in population ethics, including by all of the fundamental impossibility theorems. (shrink)

This essay introduces a new type of measure of social welfare, where populations are evaluated by their resemblance to an optimum population, which is an (in principle) possible population with the highest degree of social welfare, relative to some circumstances. Here it is argued to be the largest possible population where everyone fares maximally well. The new measure is responsive to quality of welfare, equality of welfare, and the number of people. It satisfies dominance and negative monotonicity, and it avoids (...) both the repugnant conclusion and a reverse repugnant conclusion for comparisons relative to our future on earth. (shrink)

In carrying out cost-benefit or cost-effective analysis, a discount rate should be applied to some kinds of future benefits and costs. It is controversial, though, whether future health is in this class. I argue that one of the standard arguments for discounting (from diminishing marginal returns) is inapplicable to the case of health, while another (favouring a pure rate of time preference) is unsound in any case. However, there are two other reasons that might support a positive discount rate for (...) future health: one relating to uncertainty, and the other relating to the instrumental benefits of improved health. While the latter considerations could be modelled via a discount rate, they could alternatively be modelled more explicitly, in other ways; I briefly discuss which modelling method is preferable. Finally, I argue against the common claims that failing to discount future health would lead to paradox, and/or to inconsistency with the way future cash flows are treated. (shrink)

Given the deep disagreement surrounding population axiology, one should remain uncertain about which theory is best. However, this uncertainty need not leave one neutral about which acts are better or worse. We show that as the number of lives at stake grows, the Expected Moral Value approach to axiological uncertainty systematically pushes one towards choosing the option preferred by the Total and Critical Level views, even if one’s credence in those theories is low.

Parfit’s Repugnant Conclusion argues, against intuition, that for any world A, another world Z with higher population and minimal well-being is better. That intuition is incorrect because the argument has not considered resources that support well-being. Z must have many more resources supporting well-being than A does. Z is repugnant because it spreads those resources among too many people; another world with Z’s resources and fewer people, if available, would be far superior. But Z is still better than A; it (...) is worth accepting its very large population to get the resources needed to support their well-being. (shrink)

In the face of an impossibility result, some assumption must be relaxed. The Mere Addition Paradox is an impossibility result in population ethics. Here, I explore substantially weakening the decision-theoretic assumptions involved. The central finding is that the Mere Addition Paradox persists even in the general framework of choice functions when we assume Path Independence as a minimal decision-theoretic constraint. Choice functions can be thought of either as generalizing the standard axiological assumption of a binary “betterness” relation, or as providing (...) a general framework for a normative (rather than axiological) theory of population ethics. Path Independence, a weaker assumption than typically (implicitly) made in population ethics, expresses the idea that, in making a choice from a set of alternatives, the order in which options are assessed or considered is ethically arbitrary and should not affect the final choice. Since the result establishes a conflict between the relevant ethical principles and even very weak decision-theoretic principles, we have more reason to doubt the ethical principles. (shrink)

According to lexical views in population axiology, there are good lives x and y such that some number of lives equally good as x is not worse than any number of lives equally good as y. Such views can avoid the Repugnant Conclusion without violating Transitivity or Separability, but they imply a dilemma: either some good life is better than any number of slightly worse lives, or else the ‘at least as good as’ relation on populations is radically incomplete, in (...) a sense to be explained. One might judge that the Repugnant Conclusion is preferable to each of these horns and hence embrace an Archimedean view. This is, roughly, the claim that quantity can always substitute for quality: each population is worse than a population of enough good lives. However, Archimedean views face an analogous dilemma: either some good life is better than any number of slightly worse lives, or else the ‘at least as good as’ relation on populations is radically and symmetrically incomplete, in a sense to be explained. Therefore, the lexical dilemma gives us little reason to prefer Archimedean views. Even if we give up on lexicality, problems of the same kind remain. (shrink)

According to Critical-Level Views in population axiology, an extra life improves a population only if that life’s welfare exceeds some fixed ‘critical level.’ An extra life at the critical level leaves the new population equally good as the original. According to Critical-Range Views, an extra life improves a population only if that life’s welfare exceeds some fixed ‘critical range.’ An extra life within the critical range leaves the new population incommensurable with the original. -/- In this paper, I sharpen some (...) old objections to these views and offer some new ones. Critical-Level Views cannot avoid certain Repugnant and Sadistic Conclusions. Critical-Range Views imply that lives featuring no good or bad components whatsoever can nevertheless swallow up and neutralise goodness or badness. Both classes of view entail that certain small changes in welfare correspond to worryingly large differences in contributive value. -/- I then offer a view that retains much of the appeal of Critical-Level and Critical-Range Views while avoiding the above pitfalls. On the Imprecise Exchange Rates View, the quantity of some good required to outweigh a given unit of some bad is imprecise. This imprecision is the source of incommensurability between lives and populations. (shrink)

In this essay I argue that even though egalitarianism and prioritarianism are different theories of social welfare, they can use the same social welfare measures. I present six different arguments for this thesis. The first argument is that conceptual connections between egalitarianism and prioritarianism ensure that any measure that works for either theory works for both. The second argument is that conditions necessary and sufficient to identify egalitarian and prioritarian measures, respectively, are equivalent. The third argument is that both egalitarianism (...) and prioritarianism can use two standard measures, typically proposed for only one theory. The fourth to sixth arguments contend that four properties that have been proposed as distinctive of either egalitarian or prioritarian measures cannot distinguish between them. I conclude that any egalitarian measure is also a prioritarian measure, and vice versa. (shrink)

Discussions of the non-identity problem presuppose a widely shared intuition that actions or policies that change who comes into existence don't, thereby, become morally unproblematic. We hypothesize that this intuition isn’t generally shared by the public, which could have widespread implications concerning how to generate support for large-scale, identity-affecting policies relating to matters like climate change. To test this, we ran a version of the well-known dictator game designed to mimic the public's behavior over identity-affecting choices. We found the public (...) does seem to behave more selfishly when making identity-affecting choices, which should be concerning. We further hypothesized that one possible mechanism is the notion of harm the public uses in their decision-making and find that substantial portions of the population seem to each employ distinct notions of harm in their normative thinking. These findings raise puzzling features about the public’s normative thinking that call out for further empirical examination. (shrink)

Totalism is the view that one distribution of well-being is better than another just in case the one contains a greater sum of well-being than the other. Many philosophers, following Parfit, reject totalism on the grounds that it entails the repugnant conclusion: that, for any number of excellent lives, there is some number of lives that are barely worth living whose existence would be better. This paper develops a theory of welfare aggregation—the lexical-threshold view—that allows totalism to avoid the repugnant (...) conclusion, as well as its analogues involving suffering populations and the lengths of individual lives. The theory is grounded in some independently plausible views about the structure of well-being, identifies a new source of incommensurability in population ethics, and avoids some of the implausibly extreme consequences of other lexical views, without violating the intuitive separability of lives. (shrink)

Ethics in the tradition of Derek Parfit’s Reasons and Persons is riddled with sorites-like arguments, which lead us by what seem innocent steps to seemingly false conclusions. Take, for example, spectrum arguments for the Repugnant Conclusion that appeal to slight differences in quality of life. Several authors have taken the view that, since spectrum arguments are structurally analogous to sorites arguments, the correct response to spectrum arguments is structurally analogous to the correct response to sorites arguments. This sorites analogy is (...) here argued against. There are potential structural disanalogies between spectrum arguments and sorites arguments. But even if these arguments are relevantly structurally analogous, they differ in their content in ways that show the sorites analogy to be implausible. Two content-based disanalogies are here explored—one is inspired by Parfit’s work on reductionism, and the other involves hypersensitivity. The chapter concludes with a methodological lesson. (shrink)

This chapter presents several arguments related to Parfit's notion of evaluative imprecision and his imprecisionist lexical view of population ethics. After sketching Parfit's view, it argues that, contrary to Parfit, imprecision and lexicality are both compatible with thinking about goodness in terms of positions on a scale of value. Then, by examining the role that imprecision is meant to play in defusing spectrum argument, it suggests that imprecision should be identified with vagueness. Next, it argues that there is space for (...) robust moral realists to think of evaluative vagueness as a semantic phenomenon, illustrating this view with a version of conceptual role semantics on which the precisifications of betterness are correctness conditions for the precisifications of preference. Finally, it gives a probability-based argument against the imprecisionist lexical view. (shrink)

The non-identity problem is that some actions seem morally wrong even though, by affecting future people’s identities, they are worse for nobody. In this paper, I further develop and defend a lesser-known solution to the problem, one according to which when such actions are wrong, it is not because of what they do or produce, but rather just because of why they were performed. In particular, I argue that the actions in non-identity cases are wrong just when and because they (...) result from, or reflect in those who have performed them, a morally dubious character trait. (shrink)

Derek Parfit was one of the most important and influential moral philosophers of the late 20th and early 21st centuries. This Element offers a critical introduction to his wide-ranging ethical thought, focusing especially on his two most significant works, Reasons and Persons and On What Matters, and their contribution to the consequentialist moral tradition. Topics covered include: rationality and objectivity, distributive justice, self-defeating moral theories, Parfit's Triple Theory, personal identity, and population ethics.

In this essay I propose a new measure of social welfare. It captures the intuitive idea that quantity, quality, and equality of individual welfare all matter for social welfare. More precisely, it satisfies six conditions: Equivalence, Dominance, Quality, Strict Monotonicity, Equality and Asymmetry. These state that i) populations equivalent in individual welfare are equal in social welfare; ii) a population that dominates another in individual welfare is better; iii) a population that has a higher average welfare than another population is (...) better, other things being equal; iv) the addition of a well-faring individual makes a population better, whereas the addition of an ill-faring individual makes a population worse; v) a population that has a higher degree of equality than another population is better, other things being equal; and vi) individual illfare matters more for social welfare than individual welfare. By satisfying the six conditions, the measure improves on previously proposed measures, such as the utilitarian Total and Average measures, as well as different kinds of Prioritarian measures. (shrink)

The principle of Anteriority says that prospects that are identical from the perspective of every possible person’s welfare are equally good overall. The principle enjoys prima facie plausibility, and has been employed for various theoretical purposes. Here it is shown using an analogue of the St Petersburg Paradox that Anteriority is inconsistent with central principles of axiology.

Parfit (2017) proposed a novel principle for outcome betterness in different people and different number choices. It is claimed to solve the Non-Identity Problem while avoiding the Repugnant Conclusion, and it shall do so in person-affecting rather than in impersonal terms. According to this Wide Dual Person-Affecting Principle, one of two outcomes would be (i) in one way better if this outcome would together benefit people more, and (ii) in another way better if this outcome would benefit each person more. (...) I argue that a plausible construal of this principle has two features that make it vulnerable to objections. First, the most plausible interpretation of the second part of the principle turns out to incorporate an average function. Although this helps to avoid the Repugnant Conclusion, it implausibly implies that it can be better to add further people with less bad but still miserable lives to populations consisting only of lives full of suffering. Second, the principle is not based on a comparative but on an intrinsic notion of benefit. This allows to solve the Non-Identity Problem, yet it accounts only for a weak sense of person-affecting rather than for the more substantive person-affecting intuition that it is morally significant that particular people are made better (or worse) off. Eventually, I highlight what we can, nevertheless, learn from Parfit’s idea of combining different ways in which outcomes might be better. (shrink)

This paper develops transfinite extensions of transitivity and acyclicity in the context of population ethics. They are used to argue that it is better to add good lives, worse to add bad lives, and equally good to add neutral lives, where a life's value is understood as personal value. These conclusions rule out a number of theories of population ethics, feed into an argument for the repugnant conclusion, and allow us to reduce different-number comparisons to same-number ones. Challenges to these (...) arguments are addressed, including the issue of comparing existence and non-existence in terms of personal value, the possibility of minimal quanta of time and life, and the meaningfulness of measuring closeness between outcomes with different population sizes. An asymmetry is uncovered between transfinite cycles of worseness and betterness, supporting a version of the weak procreative asymmetry. Transfinite transitivity principles are also favourably compared to the better-known principles of continuity. (shrink)

This paper presents a critique of David Benatar’s arguments on the badness of all human lives. I argue that even if Benatar is right that there is an asymmetry between the good and the bad in life so that each “unit” of bad is indeed more effective than each “unit” of good, lives in which there is a lot of good and only little bad are still overall good. Even if there are more unfulfilled than fulfilled desires in life, a (...) distinction should be drawn between desires to fulfill important goals and desires to fulfill trivial ones, and Benatar’s claim is untrue of the former. Benatar’s claim that we cannot really know that the quality of our own lives is good is problematic, but even if it were true, it would not show that we cannot estimate correctly the quality of other people’s lives, which is the point at issue. (shrink)

An updated version of this encyclopedia entry on the concept of what, if anything, makes life worthwhile.

Matthew Adler's Measuring Social Welfare is an introduction to the social welfare function (SWF) methodology. This essay questions some ideas at the core of the SWF methodology having to do with the relation between the SWF and the measure of well-being. The facts about individual well-being do not single out a particular scale on which well-being must be measured. As with physical quantities, there are multiple scales that can be used to represent the same information about well-being; no one scale (...) is special. Like physical laws, the SWF and its ranking of distributions cannot depend on exactly which of these scales we use. Adler and other theorists in the SWF tradition have used this idea to derive highly restrictive constraints on the shape of the SWF. These constraints rule out seemingly plausible views about distributive justice and population ethics. I argue, however, that these constraints stem from a simple but instructive mistake. The SWF should not be applied to vectors of numbers such as 1 and 2, but rather to vectors of dimensioned quantities such as 1 util and 2 utils. This seemingly pedantic suggestion turns out to have far-reaching consequences. Unlike the orthodox SWF approach, treating welfare levels as dimensioned quantities lets us distinguish between real changes in well-being and mere changes in the unit of measurement. It does this without making the SWF depend on the scale on which welfare is measured, and in a way that avoids the restrictive constraints on the shape of the SWF. (shrink)

Economic policy evaluations require social welfare functions for variable-size populations. Two important candidates are critical-level generalized utilitarianism (CLGU) and rank-discounted critical-level generalized utilitarianism, which was recently characterized by Asheim and Zuber (2014) (AZ). AZ introduce a novel axiom, existence of egalitarian equivalence (EEE). First, we show that, under some uncontroversial criteria for a plausible social welfare relation, EEE suffices to rule out the Repugnant Conclusion of population ethics (without AZ’s other novel axioms). Second, we provide a new characterization of CLGU: (...) AZ’s set of axioms is equivalent to CLGU when EEE is replaced by the axiom same-number independence. (shrink)

Arrhenius’s impossibility theorems purport to demonstrate that no population axiology can satisfy each of a small number of intuitively compelling adequacy conditions. However, it has recently been pointed out that each theorem depends on a dubious assumption: Finite Fine-Grainedness. This assumption states that there exists a finite sequence of slight welfare differences between any two welfare levels. Denying Finite Fine-Grainedness makes room for a lexical population axiology which satisfies all of the compelling adequacy conditions in each theorem. Therefore, Arrhenius’s theorems (...) fail to prove that there is no satisfactory population axiology. In this paper, I argue that Arrhenius’s theorems can be repurposed. Since all of our population-affecting actions have a non-zero probability of bringing about more than one distinct population, it is population prospect axiologies that are of practical relevance, and amended versions of Arrhenius’s theorems demonstrate that there is no satisfactory population prospect axiology. These impossibility theorems do not depend on Finite Fine-Grainedness, so lexical views do not escape them. (shrink)

A possible person’s conditional expected well-being is what the quality of their prospects would be if they were to come into existence. This paper examines the role that this form of expected well-being should play in distributing benefits among prospective people and in deciding who to bring into existence. It argues for a novel egalitarian view on which it is important to ensure equality in people’s life prospects, not merely between actual individuals, but also between all individuals who, given our (...) choices, have a chance of coming into existence. The paper argues that such egalitarianism for prospective people springs from equal concern for each person and has plausible implications. It further shows that it has a rationale in respect for both the unity of the individual and the separateness of persons. Finally, it defends this view against a key objection and shows it is superior to a rival view. (shrink)

Suppose you found that the universe around you was infinite—that it extended infinitely far in space or in time and, as a result, contained infinitely many persons. How should this change your moral decision-making? Radically, it seems, according to some philosophers. According to various recent arguments, any moral theory that is ’minimally aggregative’ will deliver absurd judgements in practice if the universe is (even remotely likely to be) infinite. This seems like sound justification for abandoning any such theory. -/- My (...) goal in this thesis is simple: to demonstrate that we need not abandon minimally aggregative theories, even if we happen to live in an infinite universe. I develop and motivate an extension of such theories, which delivers plausible judgements in a range of realistic cases. I show that this extended theory can overcome key objections—both old and new—and that it succeeds where other proposals do not. With this proposal in hand, we can indeed retain minimally aggregative theories and continue to make moral decisions based on what will promote the good. (shrink)

The Repugnant Conclusion served an important purpose in catalyzing and inspiring the pioneering stage of population ethics research. We believe, however, that the Repugnant Conclusion now receives too much focus. Avoiding the Repugnant Conclusion should no longer be the central goal driving population ethics research, despite its importance to the fundamental accomplishments of the existing literature.

While morality prohibits us from creating miserable children, it does not require us to create happy children. I offer an actualist explanation of this apparent asymmetry. Assume that for every possible world W, there is a distinct set of permissibility facts determined by the welfare of those who exist in W. Moral actualism says that actual-world permissibility facts should determine one's choice between worlds. But if one doesn't know which world is actual, one must aim for subjective rightness and maximize (...) expected actual-world permissibility. So, because one should expect actual people to be worse off than they could have been if one creates a miserable child, creating a miserable child is subjectively impermissible. And because one should expect actual people to be at least as well off as they could have been if one fails to create a happy child, failing to create a happy child is subjectively permissible. (shrink)

Critical-Range Utilitarianism is a variant of Total Utilitarianism which can avoid both the Repugnant Conclusion and the Sadistic Conclusion in population ethics. Yet Standard Critical-Range Utilitarianism entails the Weak Sadistic Conclusion, that is, it entails that each population consisting of lives at a bad well-being level is not worse than some population consisting of lives at a good well-being level. In this paper, I defend a version of Critical-Range Utilitarianism which does not entail the Weak Sadistic Conclusion. This is made (...) possible by a fourth category of absolute value in addition to goodness, badness, and neutrality. (shrink)

In the posthumously published ‘Future People, the Non-Identity Problem, and Person-Affecting Principles’, Derek Parfit presents a novel axiological principle which he calls the Wide Dual Person-Affecting Principle and claims that it does not imply the Repugnant Conclusion. This paper shows that even the best version of Parfit's principle cannot avoid this conclusion. That said, accepting such a principle makes embracing the Repugnant Conclusion more justifiable. This paper further addresses important questions which Parfit left unanswered concerning: the relative importance of individual (...) and collective goodness, comparisons involving unequal outcomes, how to understand individual goodness, and whether incomparability at the level of individual goodness implies incomparability at the level of overall goodness. (shrink)

We give two social aggregation theorems under conditions of risk, one for constant population cases, the other an extension to variable populations. Intra and interpersonal welfare comparisons are encoded in a single ‘individual preorder’. The theorems give axioms that uniquely determine a social preorder in terms of this individual preorder. The social preorders described by these theorems have features that may be considered characteristic of Harsanyi-style utilitarianism, such as indifference to ex ante and ex post equality. However, the theorems are (...) also consistent with the rejection of all of the expected utility axioms, completeness, continuity, and independence, at both the individual and social levels. In that sense, expected utility is inessential to Harsanyi-style utilitarianism. In fact, the variable population theorem imposes only a mild constraint on the individual preorder, while the constant population theorem imposes no constraint at all. We then derive further results under the assumption of our basic axioms. First, the individual preorder satisfies the main expected utility axiom of strong independence if and only if the social preorder has a vector-valued expected total utility representation, covering Harsanyi’s utilitarian theorem as a special case. Second, stronger utilitarian-friendly assumptions, like Pareto or strong separability, are essentially equivalent to strong independence. Third, if the individual preorder satisfies a ‘local expected utility’ condition popular in non-expected utility theory, then the social preorder has a ‘local expected total utility’ representation. Fourth, a wide range of non-expected utility theories nevertheless lead to social preorders of outcomes that have been seen as canonically egalitarian, such as rank-dependent social preorders. Although our aggregation theorems are stated under conditions of risk, they are valid in more general frameworks for representing uncertainty or ambiguity. (shrink)

According to the person-affecting restriction, one distribution of welfare can be better than another only if there is someone for whom it is better. Extant problems for the person-affecting restriction involve variable-population cases, such as the nonidentity problem, which are notoriously controversial and difficult to resolve. This paper develops a fixed-population problem for the person-affecting restriction. The problem reveals that, in the presence of incommensurable welfare levels, the person-affecting restriction is incompatible with minimal requirements of impartial beneficence even in fixed-population (...) contexts. (shrink)

Derek Parfit (1942–2017) is widely considered to be one of the most important moral philosophers of the twentieth century. Reasons and Persons is arguably the most influential of the two books published in his lifetime and hailed as a classic work of ethics and personal identity. Derek Parfit’s Reasons and Persons: An Introduction and Critical Inquiry is an outstanding introduction to and assessment of Parfit’s book, with chapters by leading scholars of ethics, metaphysics and of Parfit’s work. Part I provides (...) a much-needed introduction to key topics and themes in Reasons and Persons that will be useful for those new to Parfit’s complex work. These include Parfit’s idea of self-defeating theories, rationality and time, personal identity, future generations and well-being. Part II explores various debates generated by Reasons and Persons, including its connections with Buddhism, metaethics, theory of rationality, transformative choices and further developments in personal identity and metaphysics such as conativism. Combining clear exposition of the major topics and arguments in Reasons and Persons with scholarly perspectives on more advanced themes, this book is ideal for students of ethics, metaethics, metaphysics and anyone interested in Derek Parfit’s philosophy. (shrink)

A foundational problem in population ethics is the “repugnant conclusion", introduced by Derek Parfit in Reasons and Persons. It holds that for any possible population of at least ten billion lives of very high positive welfare, there is some larger possible population of lives of very low positive welfare whose existence would be better, if other things are equal. I call this claim RC1. In this article, I argue that by carefully considering the nature and variety of possible lives of (...) very low positive welfare, and distinguishing RC1 from a related but stronger claim I call RC2, we can show that RC1 is more acceptable than it first appears. It has been claimed that perfectionism— that is, a special concern for the best things in life—is a reason to reject the repugnant conclusion. I argue that although perfectionism gives us a reason to reject RC2, it does not give us any reason to reject, and might in fact support, RC1. In his last two papers on the subject, Parfit develops a strategy for avoiding the repugnant conclusion that appeals in part to perfectionism. In the final part of this article, I argue that Parfit’s strategy can help us avoid RC2 but not RC1. If I am right that RC1 is more acceptable than RC2, this may not be an unwelcome result. (shrink)

How might we extend aggregative moral theories to compare infinite worlds? In particular, how might we extend them to compare worlds with infinite spatial volume, infinite temporal duration, and infinitely many morally valuable phenomena? When doing so, we face various impossibility results from the existing literature. For instance, the view we adopt can endorse the claim that worlds are made better if we increase the value in every region of space and time, or that they are made better if we (...) increase the value obtained by every person. But they cannot endorse both claims, so we must choose. In this paper I show that, if we choose the latter, our view will face serious problems such as generating incomparability in many realistic cases. Opting instead to endorse the first claim, I articulate and defend a spatiotemporal, expansionist view of infinite aggregation. Spatiotemporal views such as this do face some difficulties, but I show that these can be overcome. With modification, they can provide plausible comparisons in cases that we care about most. (shrink)

In this paper we distinguish two versions of the non-identity problem: one involving positive well-being and one involving negative well-being. Intuitively, there seems to be a difference between the two versions of the problem. In the negative case it is clear that one ought to cause the better off person to exist. However, it has recently been suggested that this is not so in the positive case. We argue that such an asymmetrical treatment of the two versions should be rejected (...) and that this is evidence against views according to which it is permissible to cause the less well off person to exist in the positive non-identity case. (shrink)

In population ethics, Narveson’s dictum states: morality favours making people happy, but is neutral about making happy people. The thought is intuitively appealing; for example, it prohibits creating new people at the expense of those who already exist. However, there are well-known obstacles to accommodating Narveson’s dictum within a standard framework of overall betterness: any attempt to do so violates very plausible formal features of betterness. Therefore, the prevailing view is that the dictum is off-limits to consequentialists, who are thereby (...) committed to the unsavoury normative consequences of denying it. We argue against the prevailing view, by showing that Narveson’s dictum can be accommodated within “multidimensional” consequentialism. The key move is to deny the normative preeminence of overall betterness, instead taking moral decision-making to rest directly on “respects” of betterness. The multidimensional approach permits a consequentialist account of Narveson’s dictum in which betterness is well-behaved. It also yields a new way to think of the connection between goodness and rightness, thus revealing new terrain in the space of possible moral theories. (shrink)

Recently, Derek Parfit has offered a novel solution to the “Repugnant Conclusion” that compared with the existence of many people whose quality of life would be very high, there is some much larger number of people whose existence would be better but whose lives would be barely worth living. On this solution, qualitative differences between two populations will often entail that the populations are merely “imprecisely” comparable. According to Parfit, this fact allows us to avoid the Repugnant Conclusion without violating (...) the transitivity of better than. In this paper, I argue that Parfit’s view nevertheless implies two objectionable conclusions. The first is an alternative version of the Repugnant Conclusion that, Parfit suggests, may not be all that repugnant. The second is a revised version of the first that is nearly identical to the Repugnant Conclusion. I conclude that Parfit’s view offers no escape from repugnance. (shrink)

We analyze the role of ethical values in the determination of the social cost of carbon, arguing that the familiar debate about discounting is too narrow. Other ethical issues are equally important to computing the social cost of carbon, and we highlight inequality, risk, and population ethics. Although the usual approach, in the economics of cost-benefit analysis for climate policy, is confined to a utilitarian axiology, the methodology of the social cost of carbon is rather flexible and can be expanded (...) to a broader set of social-welfare approaches. [Open access]. (shrink)

In a typical non-identity case, the agent performs an action that causes someone to exist at a low but positive level of well-being, although an alternative was to create another, much happier person instead. There seem to be strong moral reasons against what the agent does, but it is difficult to explain how this can be so. In particular, it seems that on a simple counterfactual account of harm, the action does not harm anyone, as it does not make anyone (...) worse off than he or she would have been had the action not been performed. In this paper, I criticize the response that the action nevertheless harms the actual child, as well as the response that it makes the counterfactual child worse off. I argue that the following alternative view deserves attention: a compound of the actual and the counterfactual child is made worse off by the action. (shrink)

The non-identity problem is usually considered in the forward-looking direction but a version of it also applies to the past, due to the fact that even minor historical changes would have affected the whole subsequent sequence of births, dramatically changing who comes to exist next. This simple point is routinely overlooked by familiar attitudes and evaluative judgments about the past, even those of sophisticated historians. I shall argue, however, that it means that when we feel sadness about some historical tragedy, (...) or think of one possible course of history as better than another, these judgments and attitudes can be understood in terms of two opposing perspectives on the past: an impersonal standpoint concerned only with how much value each course of history contains, and a person-centred standpoint concerned with harms and benefits to the people who had actually existed. In this paper, I will set out these radically different visions of what matters in history and point out some of their surprising implications. (shrink)