Our thesis is that there is no moral requirement to refrain from emitting reasonable amounts of greenhouse gases solely in order to enjoy oneself. Joyriding in a gas guzzler provides our paradigm example. We first distinguish this claim that there is no moral requirement to refrain from joyguzzling from other more radical claims. We then review several different proposed objections to our view. These include: the claim that joyguzzling exemplifies a vice, causes or contributes to harm, has negative expected value, (...) exceeds our fair share of global emissions, and undermines political duties. We show why none of these objections succeeds and conclude that no good reason has yet been proposed that shows why joyguzzling violates a moral requirement. (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.

Sometimes ignorance is an excuse. If an agent did not know and could not have known that her action would realize some bad outcome, then it is plausible to maintain that she is not to blame for realizing that outcome, even when the act that leads to this outcome is wrong. This general thought can be brought to bear in the context of climate change insofar as we think (a) that the actions of individual agents play some role in realizing (...) climate harms and (b) that these actions are apt targets for being considered right or wrong. Are agents who are ignorant about climate change and the way their actions contribute to it excused because of their ignorance, or is their ignorance culpable? In this paper I examine these questions from the perspective of recent developments in the theories of responsibility for ignorant action and characterize their verdicts. After developing some objections to existing attempts to explore these questions, I characterize two influential theories of moral responsibility and discuss their implications for three different types of ignorance about climate change. I conclude with some recommendations for how we should react to the face of the theories' conflicting verdicts. The answer to the question posed in the title, then, is: "Well, it's complicated.". (shrink)

This paper distinguishes between five different approaches to social discount rates in climate change economics, criticizes two of these, and explains how the other three are to some degree mutually compatible. It aims to shed some new light on a longstanding debate in climate change economics between so-called “descriptivists” and “prescriptivists” about social discounting. The ultimate goal is to offer a sketch of the conceptual landscape that makes visible some important facets of the debate that very often go unacknowledged.

Utilitarians must think collectively about the future because many contemporary moral issues require collective responses to avoid possible future harms. But current rule utilitarianism does not accommodate the distant future. Drawing on my recent books Future People and Ethics for a Broken World, I defend a new utilitarianism whose central ethical question is: What moral code should we teach the next generation? This new theory honours utilitarianism’s past and provides the flexibility to adapt to the full range of credible futures (...) – from futures broken by climate change to the digital, virtual and predictable futures produced by various possible technologies. (shrink)

Several areas of welfare economics seek to evaluate states of affairs as a function of interpersonally comparable individual utilities. The aim is to map each state of affairs onto a vector of individual utilities, and then to produce an ordering of these vectors that can be represented by a mathematical function assigning a real number to each. When this approach is used in intertemporal contexts, a central theoretical question concerns the evaluative weight to be applied to utility coming at different (...) times. This question concerns the rate of pure time preference, which is one key determinant of the social discount rate. This article argues that the standard philosophical account of pure time preference is mistaken, because it ascribes to economists a methodological commitment they need not, and often do not, accept. This in turn undercuts the most common philosophical objection to pure time preference, which traces at least to Rawls’s A Theory of Justice. The article then evaluates three further objections to pure time preference, concluding that it might still be defensible under certain circumstances. The article closes by articulating a final argument that is suggested by the “Social, Economic and Ethical Concepts and Methods” chapter of the most recent Intergovernmental Panel on Climate Change report. If this further argument is sound, it would constitute a decisive objection to pure time preference as it currently figures in much intertemporal welfare economics. (shrink)

We naturally attribute obligations to groups, and take such obligations to have consequences for the obligations of group members. The threat posed by anthropogenic climate change provides an urgent case. It seems that we, together, have an obligation to prevent climate catastrophe, and that we, as individuals, have an obligation to contribute. However, understood strictly, attributions of obligations to groups might seem illegitimate. On the one hand, the groups in question—the people alive today, say—are rarely fully-fledged moral agents, making it (...) unclear how they can be subjects of obligations. On the other, the attributions can rarely be understood distributively, as concerned with members’ obligations, because obligations to do something require a capacity to do it, and individual members often lack the relevant capacities. Moreover, even if groups can have obligations, it is unclear why that would be relevant for members, exactly because members often lack control over whether group obligations are fulfilled. In previous work, I have argued that a general understanding of individual obligations extends non-mysteriously to irreducibly shared obligations, rendering attributions of obligations to groups legitimate. In this paper, I spell out how the proposed account also helps us understand the relation between individual and shared obligations. Even though few individual human agents have any significant control over whether we will be successful in preventing climate catastrophe, our collective capacity to prevent catastrophe and shared preventative obligation to do so can give rise to significant individual obligations to contribute to its fulfillment. (shrink)

This article introduces a non-human version of the non-identity problem and suggests that such a variation exposes weaknesses in several proposed person-focused solutions to the classic version of the problem. It suggests first that person-affecting solutions fail when applied to non-human animals and, second, that many common moral arguments against climate change should be called into question. We argue that a more inclusive version of the person-affecting principle, which we call the ‘patient-affecting principle’, captures more accurately the moral challenge posed (...) by the non-identity problem. We argue further that the failure of person-affecting solutions to solve non-human versions of the problem lend support to impersonal solutions to the problem which avoid issues of personhood or species identity. Finally, we conclude that some environmental arguments against climate change that rely on the notion of personal harm should be recast in impersonal terms. (shrink)

In an earlier article I argued that individuals are obligated not to exceed their fair share of emissions entitlements, that many exceed their fair share at present and thus ought to reduce their emissions as far as can reasonably be demanded. The peer commentators raised various insightful and pressing concerns, but the following objections seem particularly important: It was argued that the fair share argument is insufficiently justified, that it is incoherent, that it would result in more far-reaching duties than (...) acknowledged by me, that it is unable to provide a clear account of individual duties, and that duties to reduce individual emissions are not Kantian imperfect duties. This reply aims at clarifying the fair share argument and at addressing the major challenges. (shrink)

In this paper I claim that there are moral reasons for making climate denialism illegal. First I define climate denialism, and then I discuss its impact on society and its reception in the media. I build my philosophical arguments mainly on John Stuart Mill and Thomas M. Scanlon. According to Mill’s utilitarian justification of free speech, even untrue opinions are valuable in society’s pursuit of more truth. Consequently one might think that Mill’s philosophy would justify climate denialists’ right to free (...) speech. A major section of the paper argues against that view. The main arguments are: Climate denialism is not beneficial because its main goal is to produce doubt, and not truth. Climate denialism is not sincerely meant, which is a necessary condition for Mill to accept utterances. Climate denialists bring harm, by blocking necessary action on climate change. Primarily they harm future generations and people in developing countries. Hence the case can be made in terms of global justice: Would future generations and people in developing countries support my claim? I think so, or so I argue. My argument from global justice is built on Scanlon’s distinction between the interests of participants, the interests of audiences, and the interests of bystanders. The climate denialists have participant interests ‘in being able to call something to the attention of a wide audience’. Audience interests consist in ‘having access to expressions that we wish to hear or read, and even in being exposed to some degree to expressions we have not chosen’. Future generations and people in poor countries are bystanders to the climate debate. If the debate postpones necessary actions, it is the bystanders who must pay the price. I argue that bystanders’ costs outweigh participants’ and audiences’ interests, and that this is an argument for a statutory ban on climate denialism.Article first published online: 21 DEC 2015. (shrink)

Individuals have various kinds of obligations: keep promises, don’t cause harm, return benefits received from injustices, be partial to loved ones, help the needy and so on. How does this work for group agents? There are two questions here. The first is whether groups can bear the same kinds of obligations as individuals. The second is whether groups’ pro tanto obligations plug into what they all-things-considered ought to do to the same degree that individuals’ pro tanto obligations plug into what (...) they all-things-considered ought to do. We argue for parity on both counts. (shrink)

Personal carbon footprints have become a subject of major concern among those who worry about global climate change. Conventional wisdom holds that individuals have a duty to reduce their impacts on the climate system by restricting their carbon footprints. However, I defend a new argument for thinking that this conventional wisdom is mistaken. Individuals, I argue, have a duty to take actions to combat the world’s problems. But since climate change is only one of a nearly endless list of such (...) problems, individuals’ obligations to take action as activists do not specifically require reductions in personal carbon footprints. Moreover, this is true even in spite of the fact that we are personally implicated in causing climate change. This paper also argues that many of those who decide to combat climate change by reducing their carbon footprints are likely doing more than they can justify in this regard. Although most people are not doing enough to combat world problems, a proper devotion to activism would seek a balance with other life demands that many climate activists currently eschew. (shrink)

Two related asymmetries have been discussed in relation to the ethics of creating new lives: First, we seem to have strong moral reason to avoid creating lives that are not worth living, but no moral reason to create lives that are worth living. Second, we seem to have strong moral reason to improve the wellbeing of existing lives, but, again, no moral reason to create lives that are worth living. Both asymmetries have proven very difficult to account for in any (...) coherent moral framework. I propose an impersonal population axiology to underpin the asymmetries, which sidesteps the problematic issue of whether or not people can be harmed or benefited by creation or non-creation. This axiology yields perfect asymmetry from a deliberative perspective, in terms of expected value. The axiology also yields substantial asymmetry for large and realistic populations in terms of their actual value, beyond deliberative relevance. (shrink)

This paper discusses two distinct questions of distributive justice raised by climate change. Stated very roughly, one question concerns how much protection is owed to the potential victims of climate change (the Just Target Question), and the second concerns how the burdens (and benefits) involved in preventing dangerous climate change should be distributed (the Just Burden Question). In Section II, I focus on the first of these questions, the Just Target Question. The rest of the paper examines the second question, (...) the Just Burden Question. To answer this question, I argue, it is necessary to address two important methodological questions (one concerning the choice between what I term Integrationism and Isolationism and the other concerning the choice between what I term Holism and Atomism). Sections III-V, thus, set out and explore these two methodological issues. Having done so, the paper then turns from methodological issues to substantive analysis, and in Section VI it examines three principles of distributive justice that, it has been suggested, should determine how the burden of addressing dangerous climatic changes should be distributed (the Polluter Pays Principle, the Ability to Pay Principle and the Beneficiary Pays Principle). (shrink)

The Intergovernmental Panel on Climate Change has developed a novel framework for assessing and communicating uncertainty in the findings published in their periodic assessment reports. But how should these uncertainty assessments inform decisions? We take a formal decision-making perspective to investigate how scientific input formulated in the IPCC’s novel framework might inform decisions in a principled way through a normative decision model.

Obstacles to achieving a global climate treaty include disagreements about questions of justice raised by the UNFCCC's principle that countries should respond to climate change by taking cooperative action "in accordance with their common but differentiated responsibilities and respective capabilities and their social and economic conditions". Aiming to circumvent such disagreements, Climate Change Justice authors Eric Posner and David Weisbach argue against shaping treaty proposals according to requirements of either distributive or corrective justice. The USA's climate envoy, Todd Stern, takes (...) a similar position. In this article I explain the practical and theoretical drawbacks of Posner & Weisbach's welfarist perspective and propose an alternative. I show that their arguments fail to rule out John Rawls' non-utilitarian, political conception of international justice and human rights, the Law of Peoples. On this basis I develop a conception of climate justice that highlights implications of some of Rawls' principles and adds a principle for determining fair shares of climate -treaty-related benefits and burdens. I propose this conception as a moral framework for negotiating a treaty that would promote human welfare consistently with requirements of justice, and I argue that a treaty proposal satisfying these requirements could best satisfy Posner & Weisbach's own feasibility criteria. (shrink)

Liberal proponents of genetic engineering maintain that developing human germline modification technologies is morally desirable because it will result in a net improvement in human health and well-being. Skeptics of germline modification, in contrast, fear evolutionary harms that could flow from intervening in the human germline, and worry that such programs, even if well intentioned, could lead to a recapitulation of the scientifically and morally discredited projects of the old eugenics. Some bioconservatives have appealed as well to the value of (...) retaining our “given” human biological nature as a reason for restraining the development and use of human genetic modification technologies even where they would tend to increase well-being. In this article, I argue that germline intervention will be necessary merely to sustain the levels of genetic health that we presently enjoy for future generations—a goal that should appeal to bioliberals and bioconservatives alike. This is due to the population-genetic consequences of relaxed selection pressures in human populations caused by the increasing efficacy and availability of conventional medicine. This heterodox conclusion, which I present as a problem of intergenerational justice, has been overlooked in medicine and bioethics due to certain misconceptions about human evolution, which I attempt to rectify, as well as the sordid history of Darwinian approaches to medicine and social policy, which I distinguish from the present argument. (shrink)

This paper examines a broad range of ethical perspectives and principles relevant to the analysis of issues raised by the science of climate change and explores their implications. A second and companion paper extends this analysis to the contribution of ethics, economics and politics in understanding policy towards climate change. These tasks must start with the science which tells us that this is a problem of risk management on an immense scale. Risks on this scale take us far outside the (...) familiar policy questions and standard, largely marginal, techniques commonly used by economists; this is a subject that requires the full breadth and depth of what economics has to offer and a much more thoughtful view of ethics than economists usually bring to bear. Different philosophical approaches bring different perspectives on understanding and policy, yet they generally point to the case for strong action to manage climate change. (shrink)

John Broome claims that there is a sacrifice-free solution to climate change. He says this is a consequence of elementary economics. After explaining the economic argument in somewhat more detail than Broome, I show that the argument is unsound. A main problem with it stems from Derek Parfit's ‘nonidentity effect.’ But there is hope, since the nonidentity effect underwrites a more philosophical yet more plausible route to a sacrifice-free solution. So in the end I join Broome in asking economists and (...) policymakers to help make this a reality. (shrink)

Several prominent voices have called for a democratization of science through deliberative processes that include a diverse range of perspectives and values. We bring these scholars into conversation with extant research on democratic deliberation in political theory and the social sciences. In doing so, we identify systematic barriers to the effectiveness of inclusive deliberation in both scientific and political settings. We are particularly interested in what we call misidentified dissent, where deliberations are starkly framed at the outset in terms of (...) dissenting positions without properly distinguishing the kinds of difference and disagreement motivating dissent. (shrink)

I argue that moral philosophers have either misunderstood the problem of moral demandingness or at least failed to recognize important dimensions of the problem that undermine many standard assumptions. It has been assumed that utilitarianism concretely directs us to maximize welfare within a generation by transferring resources to people currently living in extreme poverty. In fact, utilitarianism seems to imply that any obligation to help people who are currently badly off is trumped by obligations to undertake actions targeted at improving (...) the value of the long-term future. Reflecting on the demands of beneficence in respect of the value of the far future forces us to view key aspects of the problem of moral demandingness in a very different light. GPI Working Paper No. 1-2020. (shrink)

Ideal carbon tax policy is internationally coordinated, fully internalizes externalities, redistributes revenues to those harmed, and is politically acceptable, generating predictable market signals. Since nonideal circumstances rarely allow all these conditions to be met, moral issues arise. This paper surveys some of the work in moral philosophy responding to several of these issues. First, it discusses the moral drivers for estimates of the social cost of carbon. Second, it explains how national self-interest can block climate action and suggests international policies—carbon (...) border tax adjustments and carbon clubs—that can help address these concerns. Third, it introduces some of the social science literature about the political acceptability of carbon taxes before addressing a couple common public concerns about carbon taxes. Finally, it introduces four carbon revenue usage options, arguing that redistributive and climate compensation measures are most morally justified. [Open access]. (shrink)

In this article, we claim that recent developments in climate science and renewable energy should prompt a reframing of debates surrounding climate change mitigation. Taken together, we argue that these developments suggest (1) global climate collapse in this century is a non-negligible risk, (2) mitigation offers substantial benefits to current generations, and (3) mitigation by some can generate social tipping dynamics that could ultimately make renewables cheaper than fossil fuels. We explain how these claims undermine familiar framings of climate change, (...) wherein mitigation is understood as self-sacrifice that individuals and governments must be morally persuaded or incentivized to undertake. [Open access]. (shrink)

Do carbon-offsetting schemes morally offset emissions? The moral equivalence thesis is the claim that the combination of emitting greenhouse gasses and offsetting those emissions is morally equivalent to not emitting at all. This thesis implies that in response to climate change, we need not make any lifestyle changes to reduce our emissions as long as we offset them. An influential argument in favor of this thesis is premised on two claims, one empirical and the other normative: (1) When you emit (...) + offset, the net result is the same as that of not emitting. (2) With emissions, the net result is what matters morally. I argue against both premises. The net result of emitting + offsetting is never equivalent to that of not emitting, and even if it were equivalent, the net result is not the only thing that matters morally. My conclusion is that although we should offset our emissions, avoiding emissions is morally preferable. This conclusion supports a stronger claim: that carbon offsets cannot relieve us of our duty to make significant lifestyle changes so as to reduce emissions and thus lesson our contribution to the harms of climate change. (shrink)

Many governments are failing to act sufficiently strongly on climate change. Given this, what should motivated affluent individuals in high-consumption societies do? This paper argues that social norms are a particularly valuable target for individual climate action. Within norm-promotion, the paper makes the case for a focus on anti-fossil fuel norms specifically. Section 1 outlines gaps in the existing literature on individuals’ climate change obligations. Section 2 characterises social norms. Section 3 provides seven reasons why social norms are a particularly (...) worthy target for individual climate actors. Section 4 asks which social norms individuals should emphasise, arguing that anti-fossil fuel norms have advantages over emissions reduction and offsetting norms. Section 5 outlines the pathways and mechanisms individuals might exploit to promote anti-fossil fuel norms. (shrink)

In this paper I examine the relation between Social Cost of Carbon (SCC) estimates, abatement cost analyses, and individual climate duties. I first highlight the stakes that SCC and abatement cost estimates potentially have for the content of individual duties to either pay the full or fair cost of their carbon emissions, or offset the volume of their emissions. I survey four methodological options (a minimalist approach, a precautionary approach, an averaging approach, and what I call a ‘sufficiency-bounded’ precautionary approach) (...) for conceptualizing the terrain of individual duties in light of SCC and abatement cost estimates that are both contentious and evolving. (shrink)

A straightforward way to handle moral uncertainty is simply to follow the moral theory in which you have most credence. This approach is known as My Favourite Theory. In this paper, I argue that, in some cases, My Favourite Theory prescribes choices that are, sequentially, worse in expected moral value than the opposite choices according to each moral theory you have any credence in. In addition this, problem generalizes to other approaches that avoid intertheoretic comparisons of value, such as My (...) Favourite Option, the Borda Rule, Variance Normalization, and the Principle of Maximizing Expected Normalized Moral Value. (shrink)

Individualist normative theories appear inadequate for the complex moral challenges of climate change. In climate ethics, this is especially notable with the relative marginalization of Kant. I argue that Kant’s philosophy, understood through its historical and cosmopolitan dimensions, has untapped potential for the climate crisis. First, I situate Kant in climate ethics and evaluate his marginalization due to perceived individualism, interiority and anthropocentrism. Then, I explore aspects of Kant’s historical and cosmopolitan writings, which present a global, future-orientated picture of humanity. (...) Ultimately, Kant’s philosophy offers a unique take on the climate deadlock capable of sustaining the individual in the collective. (shrink)

It is typically wrong to act in a way that foreseeably makes some impending harm worse. Sometimes it is permissible to do so, however, if one also offsets the harm increasing action by doing something that decreases the badness of the same harm by at least as much. This chapter argues that the standard deontological constraint against doing harm is not compatible with the permissibility of harm increases that have been offset. Offsetting neither prevents one's other actions from doing harm (...) nor ensures that the harm those actions do is made permissible by any of the constraint's familiar provisos. To make sense of offsetting, the old constraint against doing harm should be replaced with a new constraint against making unoffset harm increases. The chapter discusses how to formulate the new constraint so that it can handle both the offsetting cases that the old constraint gets wrong as as well as the non-offsetting cases that the old constraint gets right. Adopting this constraint against unoffset harm increases may have important implications both for theoretical questions about the sources of deontological constraints as well as for practical questions, such as whether buying carbon offsets can make emitting carbon dioxide permissible. (shrink)

This paper argues against the call to democratize artificial intelligence (AI). Several authors demand to reap purported benefits that rest in direct and broad participation: In the governance of AI, more people should be more involved in more decisions about AI—from development and design to deployment. This paper opposes this call. The paper presents five objections against broadening and deepening public participation in the governance of AI. The paper begins by reviewing the literature and carving out a set of claims (...) that are associated with the call to “democratize AI”. It then argues that such a democratization of AI (1) rests on weak grounds, because it does not answer to a demand of legitimization, (2) is redundant in that it overlaps with existing governance structures, (3) is resource intensive, which leads to injustices, (4) is morally myopic and thereby creates popular oversights and moral problems of its own, and finally, (5) is neither theoretically nor practically the right kind of response to the injustices that animate the call. The paper concludes by suggesting that AI should be democratized not by broadening and deepening participation but by increasing the democratic quality of the administrative and executive elements of collective decision making. In a slogan: The question is not so much whether AI should be democratized but how. (shrink)

Ruth Chang and Joseph Raz have both drawn far-reaching consequences for agency from the phenomenon of incommensurability. After criticizing their arguments, I outline an alternative view: if incommensurability is vagueness, then there are no substantial implications for agency, except perhaps a limited form of naturalistic voluntarism if our reasons are provided by desires.

Climate ethics has been concerned with polluter pays, beneficiary pays and ability to pay principles, all of which consider climate change as a single negative externality. This paper considers it as a constellation of externalities, positive and negative, with different associated demands of justice. This is important because explicitly considering positive externalities has not to our knowledge been done in the climate ethics literature. Specifically, it is argued that those who enjoy passive gains from climate change owe gains not to (...) the net losers, but to the emitters, just as the emitters owe compensation to the net losers for the negative externality. This is defended by appeal to theoretical virtues and to the social benefits of generating positive externalities, even when those positive externalities are coupled with far greater negative externalities. We call this the Polluter Pays, Then Receives ('PPTR', or 'Peter') Principle. This principle is then applied at two levels in the context of Canada. [Open access]. (shrink)

This paper asks about the climate damages that Indian policymakers can expect. What is the likely magnitude of climate damages, and how sensitive are they to the level of warming? How much worse would climate damages be for Indians under, say, 5° of warming rather than 3°? Understanding the magnitude of climate damages and how rapidly they increase as temperature change increases is critical for finding the right climate mitigation policy. This paper provides projections of India’s climate vulnerability on the (...) basis of new microeconomic and macroeconomic evidence. The authors’ quantifications show that India is highly vulnerable to climate damage. Their baseline macroeconomic approach suggests that climate change peaking at 5°C, rather than 3°C, would be as detrimental to Indian well-being as a reduction in GDP by about 18 percent for each of the years from 2020 to 2040. Such an equivalent threat to near-term economic outcomes would be an overriding policy priority if political leaders anticipated it. The authors’ microeconomic results suggest that this may be an underestimate, because it ignores humidity. Emerging evidence suggests that humans are especially vulnerable to exposure to high temperatures in contexts of high humidity; humidity is a previously underappreciated and unquantified reason way in which India may be more climate-vulnerable even than some hotter developing and middle-income countries. (shrink)

In this dissertation, I investigate the implications of libertarian morality in relation to the problem of climate change. This problem is explicated in the first chapter, where preliminary clarifications are also made. In the second chapter, I briefly explain the characteristics of libertarianism relevant to the subsequent study, including the central non-aggression principle. In chapter three, I examine whether our individual emissions of greenhouse gases, which together give rise to climate change, meet this principle. I do this based on the (...) assumption that we are the legitimate owners of the resources we use in those activities. In the fourth chapter, I question this assumption and scrutinize libertarianism’s restrictions on appropriations of climate-relevant resources, which leads me to distinguish between some different versions of the libertarian view. Toward the end of the chapter, I also examine libertarianism’s answer to the political question regarding how emission rights should be distributed. The fifth chapter investigates libertarianism’s verdicts for mere risks of infringement, as stemming from people’s emissions and acts of appropriations. In chapter six, I investigate the libertarian right to self-defense against both the effects of climate change and other people’s climate-relevant activities. In chapter seven, I discuss two intergenerational issues related to climate change: what libertarianism says concerning future generations and how libertarianism might deal with the problem of historical emissions. The eighth chapter explores the implications of libertarianism regarding collective moral wrongdoing in connection to climate change. In chapter nine, I take a look at the libertarian room for governmental responses for tackling climate change. The tenth and final chapter is a summary. The overall conclusion of the dissertation is that libertarianism recommends that we reduce our emissions and decrease our extraction of natural resources such as forests and fossil fuels. Furthermore, governments are permitted to undertake some quite substantial actions in order to fight the causes of climate change. I end with some bottom-up reflections on what these conclusions might say about the plausibility of libertarianism. I claim that although libertarianism after all manages to explain some of our moral intuitions regarding climate change, it is questionable whether libertarianism’s explanation is better than those offered by alternative moral theories. (shrink)

Future population growth is uncertain and matters for climate policy: higher growth entails more emissions and means more people will be vulnerable to climate-related impacts. We show that how future population is valued importantly determines mitigation decisions. Using the Dynamic Integrated Climate-Economy model, we explore two approaches to valuing population: a discounted version of total utilitarianism (TU), which considers total wellbeing and is standard in social cost of carbon dioxide (SCC) models, and of average utilitarianism (AU), which ignores population size (...) and sums only each time period’s discounted average wellbeing. Under both approaches, as population increases the SCC increases, but optimal peak temperature decreases. The effect is larger under TU, because it responds to the fact that a larger population means climate change hurts more people: for example, in 2025, assuming the United Nations (UN)-high rather than UN-low population scenario entails an increase in the SCC of 85% under TU vs. 5% under AU. The difference in the SCC between the two population scenarios under TU is comparable to commonly debated decisions regarding time discounting. Additionally, we estimate the avoided mitigation costs implied by plausible reductions in population growth, finding that large near-term savings ($billions annually) occur under TU; savings under AU emerge in the more distant future. These savings are larger than spending shortfalls for human development policies that may lower fertility. Finally, we show that whether lowering population growth entails overall improvements in wellbeing—rather than merely cost savings—again depends on the ethical approach to valuing population. (shrink)

The proper role of non-epistemic values such as moral, political, and social values in practices of justification of policy-relevant hypotheses has recently become one of the central questions in philosophy of science. This strand of research has yielded conceptual clarifications and significant insight into the complex and notoriously contentious issue of the proper relationship between science, non-epistemic values, and policymaking. A central part of this discussion revolves around whether scientists should aspire for the value-free ideal, according to which non-epistemic values (...) are unacceptable in the justification of hypotheses. By so doing, scientists can... (shrink)

Do we owe it to future generations, as a requirement of justice, to take action to mitigate anthropogenic climate change? This paper examines the implications of Derek Parfit’s notorious non-identity problem for that question. An argument from Jörg Tremmel that the non-identity effect of climate policy is “insignificant” is examined and found wanting, and a contrastive, difference-making approach for comparing different choices’ non-identity effects is developed. Using the approach, it is argued that the non-identity effect of a given policy response (...) to climate change depends on the contrasting policy. Compared to a baseline scenario without further mitigation, the non-identity effect of choosing to limit climate change to 1.5°C would be highly significant. (shrink)

As awareness of global warming has spread during the past couple of decades and developed into the realization that humanity faces an existential threat, a number of more or less Kantian liberal or cosmopolitan moral and political theorists have attempted to address questions of justice raised by the climate crisis. David Held was among the most prolific and influential of them. Here I discuss Held's cosmopolitan perspective on climate governance and consider its bearing on certain recent proposals for new institutions, (...) including in particular a proposal offered by John Broome and Duncan Foley for establishing a World Climate Bank. I argue that such a WCB may be endorsable from Held's perspective, depending how the initial proposal may get further developed. Held's approach to politics is similar to Kant's in certain significant respects, including the role of hope. Both approaches are valuable and important in relation to the climate crisis. (shrink)

This paper discusses some ethically relevant aspects of William Nordhaus’s contribution to climate change policy evaluation. Nordhaus's approach can shed light on one—but only one—dimension of the climate change problem. His boldest claims notwithstanding, there is nothing particularly "optimal" about the temperature increases associated with his most famous modeling choices.

Utility discounting in intertemporal economic modelling has been viewed as problematic, both for descriptive and normative reasons. However, positive utility discount rates can be defended normatively; in particular, it is rational for future utility to be discounted to take into account model-independent outcomes when decision-making under risk. The resultant values will tend to be smaller than descriptive rates under most probability assignments. This also allows us to address some objections that intertemporal considerations will be overdemanding. A principle for utility discount (...) rates is suggested which is rooted in probability discounting. Utility discounting is defended against objections from Parfit (1984) and Broome (2005); Broome (2012). A sample utility discount rate is estimated. [Open access]. (shrink)

The topic of my thesis is individual and collective responsibility for collectively caused systemic harms, with climate change as the case study. Can an individual be responsible for these harms, and if so, how? Furthermore, what does it mean to say that a collective is responsible? A related question, and the second main theme, is how ignorance and knowledge affect our responsibility. -/- My aim is to show that despite the various complexities involved, an individual can have responsibility to address (...) climate change. I argue that climate change is not a problem just for states and international bodies, but also for individuals. There are three possible sources of moral responsibility for individuals in relation to climate change harms: direct responsibility (individuals qua individuals), shared responsibility as members (individuals qua members of collective agents), and shared responsibility as constituents (individuals qua constituents of unorganised collectives). -/- Accounts that deny individual responsibility fail to either take our interdependent reality seriously or fail to understand marginal participation (or in the case direct responsibility, fail to appreciate the nature of the climate change phenomenon). Individuals can be complicit in climate change harms, either as members of collective agents (e.g. as citizens of states or employees of a corporation) or as constituents of unorganised collectives (e.g. as consumers or polluters). -/- Although I focus on individual complicity, I do not deny the obligations of collective agents. However, nation-states, governments, and international bodies are not the only relevant collective agents in climate ethics: other collective agents, such as corporations, matter also and can have obligations concerning making sure that their activities are as carbon-neutral as possible. In addition, those corporations that have engaged in lobbying against climate regulation through creating and disseminating misleading information have acquired themselves additional obligations to mitigate climate change and compensate for the harm they have caused. Even so, the ethical claims can only be understood by individual members of these collective agents because only they can feel the pull of moral claims. I suggest that we could distinguish between what one must possess in order to be capable of making moral claims (i.e. moral agency conditions), and what it means to have the ability to exhibit such claims through one’s conduct. -/- Individual direct responsibility is to not to increase the probable risk of serious harm to other people, at least as long as we can do so at a less than significant cost to ourselves. It is limited to relatively wealthy individuals. Offsetting is not a reliable way to meet this duty; we need to look at the emissions from our lifestyle choices (within the available infrastructure). Shared responsibility qua members of collective agents is the key individual responsibility, and it presses especially on those occupying key positions within key collective agents. Saying that, our shared responsibility qua constituents of unorganised collectives has the potential to be decisive in whether some action is taken or not, either through a set of actions that can signal certain acceptance or support, or as a form of political support from the grass roots. (shrink)

Much public policy analysis requires us to place a monetary value on the bad- ness of a premature human death. Currently dominant approaches to determining this ‘value of a life’ focus exclusively on the ‘self-regarding’ value of life — that is, the value of a person’s life to the person whose death is in question — and altogether ignore effects on other people. This procedure would be justified if, as seems intuitively plausible, other-regarding effects were negligible in comparison with self-regarding (...) ones. I argue that in the light of the issue of overpopulation, that intuitively plausible condition is at best highly questionable. Unless the world is in fact underpopulated, the social disvalue of a premature death is likely to be significantly lower than the current estimates. (shrink)