A survey of various candidates shows that there is no defensible moral principle that shows that individuals have an obligation to reduce their greenhouse gas emissions.

The cofounder of the Effective Altruism movement presents a counterintuitive approach anyone can use to make a difference in the world. While studying philosophy at Oxford University and trying to work out how he could have the greatest impact, William MacAskill discovered that most of the time and money aimed at making the world a better place achieves little. Why? Because individuals rarely have enough information to make the best choices. Confronting this problem head-on, MacAskill developed the concept of effective (...) altruism, a scientific, data-driven approach to making a difference that operates by asking these five questions: How much will this action improve others' lives? Is this the most effective action I can take? How useful is my contribution, given what others are already doing? What will happen if I don't do it? What are the chances of success, and how good would success be? Applying these principles, he demonstrates that many of our assumptions about doing good are misguided: he argues that one can potentially save more lives by working on Wall Street than as a heart surgeon, that cancer charities are not the best use of money, and that buying sweatshop-produced goods is a form of ethical consumption. MacAskill challenges us to think differently but argues that if we set aside our biases and rely on evidence and careful reasoning, each of us can make a tremendous difference. (shrink)

It has recently been argued that indeterminacy and indeterminism make most ordinary counterfactuals false. I argue that a plausible way to avoid such counterfactual skepticism is to postulate the existence of primitive modal facts that serve as truth-makers for counterfactual claims. Moreover, I defend a new theory of ‘might’ counterfactuals, and develop assertability and knowledge criteria to suit such unobservable ‘counterfacts’.

“Since the actions I perform as an individual only have an inconsequential effect on the threat of climate change,” a common argument goes, “it cannot be morally wrong for me to take my car to work everyday or refuse to recycle.” This argument has received a lot of scorn from philosophers over the years, but has actually been defended in some recent articles. A more systematic treatment of a central set of related issues shows how maneuvering around these issues is (...) no easy philosophical task. In the end, it appears, the argument from inconsequentialism indeed is correct in typical cases, but there are also important qualificatory considerations. (shrink)

It has sometimes been claimed (usually without evidence) that the harm caused by an individual's participation in a greenhouse-gas-intensive economy is negligible. Using data from several contemporary sources, this paper attempts to estimate the harm done by an average American. This estimate is crude, and further refinements are surely needed. But the upshot is that the average American is responsible, through his/her greenhouse gas emissions, for the suffering and/or deaths of one or two future people.

Does the decision to relax by taking a drive rather than by taking a walk cause harm? In particular, do the additional carbon emissions caused by such a decision make anyone worse off? Recently several philosophers have argued that the answer is no, and on this basis have gone on to claim that act-consequentialism cannot provide a moral reason for individuals to voluntarily reduce their emissions. The reasoning typically consists of two steps. First, the effect of individual emissions on the (...) weather is miniscule: the planet’s meteorological system is so large, and the size of individual emissions so tiny, that whatever impact an individual emission has on the weather must be vanishingly small. Second, vanishingly small impacts aren’t morally relevant because no one could possibly tell the difference between such an impact occurring and it not occurring. In this paper, we show why both steps are mistaken, and hence why act-consequentialism implies that each of us has an individual obligation to do what we can to stop damaging the climate, including by refraining from, or perhaps by purchasing offsets against, our own individual luxury carbon emissions. (shrink)

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)

Several philosophers claim that the greenhouse gas emissions from actions like a Sunday drive are so miniscule that they will make no difference whatsoever with regard to anthropogenic global climate change (AGCC) and its expected harms. This paper argues that this claim of individual causal inefficacy is false. First, if AGCC is not reducible at least in part to ordinary actions, then the cause would have to be a metaphysically odd emergent entity. Second, a plausible (dis-)utility calculation reveals that such (...) actions have a not-insignificant amount of expected harm. One upshot is that the near-exclusive focus in the literature on AGCC as a collective action problem is too restricted. The paper also provides several moral psychological explanations of why it is so difficult to comprehend individual responsibility with regard to global phenomena, including a reappraisal of Thomas Nagel’s view of the absurd. (shrink)

Collective action problems lie behind many core issues in ethics and social philosophy—for example, whether an individual is required to vote, whether it is wrong to consume products that are produced in morally objectionable ways, and many others. In these cases, it matters greatly what we together do, but yet a single individual’s ‘non-cooperative’ choice seems to make no difference to the outcome and also seems to involve no violation of anyone’s rights. Here it is argued that—contrary to influential arguments (...) by Peter Singer, Alastair Norcross, Shelly Kagan, Derek Parfit, and Allan Gibbard—an appeal to the expected consequences of acts cannot deliver plausible verdicts on many of these cases, because individuals often have a probability of making a difference that is sufficiently small to ensure that ‘non-cooperation’ is the option with the greatest expected value, even when consequentialists themselves agree that ‘cooperation’ is required. In addition, an influential argument by Singer, Norcross, and Kagan is shown to be unsound for the claim that in the collective action situations at issue, the expected effect of one individual’s action equals the average effect of everyone’s similar actions. These results have general implications for normative theory, because they undermine the sort of consequentialist explanation of collective action cases that is initially attractive from many theoretical points of view, consequentialist and otherwise. (shrink)

Several philosophers deny that an individual person’s emissions of greenhouse gas do any harm; I call these “individual denialists.” I argue that each individual’s emissions may do harm, and that they certainly do expected harm. I respond to the denialists’ arguments.

Suppose you perform two actions. The first imposes a risk of harm that, on its own, would be excessive; but the second reduces the risk of harm by a corresponding amount. By pairing the two actions together to form a set of actions that is risk-neutral, can you thereby make your overall course of conduct permissible? This question is theoretically interesting, because the answer is apparently: sometimes Yes, sometimes No. It is also practically important, because it bears on the moral (...) status of practices such as offsetting personal greenhouse gas (GHG) emissions. In this article we propose a criterion for distinguishing between cases where pairing risk-increasing and risk-reducing actions makes each action permissible, and those where it does not: the Principle of Aggregate Risk-Imposition. We work towards this by considering a range of examples that illustrate various illegitimate ways of pairing risk-increasing actions with risk-reducing ones, and asking what goes wrong in each case. We then use this criterion to evaluate GHG offsetting. Is offsetting a legitimate way of removing the risk-imposition associated with GHG emissions, or not? Controversially, we argue that this turns out to depend on the form that the offsetting takes. (shrink)

Derek Parfit presents the third volume of On What Matters, his landmark work of moral philosophy. Parfit develops further his influential treatment of reasons, normativity, the meaning of moral discourse, and the status of morality. He engages with his critics, and shows the way to resolution of their differences.

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

Many everyday actions have major but unforeseeable long-term consequences. Some argue that this fact poses a serious problem for consequentialist moral theories. We argue that the problem for non-consequentialists is greater still. Standard non-consequentialist constraints on doing harm combined with the long-run impacts of everyday actions entail, absurdly, that we should try to do as little as possible. We call this the Paralysis Argument. After laying out the argument, we consider and respond to a number of objections. We then suggest (...) what we believe is the most promising response: to accept, in practice, a highly demanding morality of beneficence with a long-term focus. (shrink)

Many companies offer their customers voluntary carbon ‘offset’ certificates to compensate for greenhouse gas emissions. Voluntary offset certificates are cheap because the demand for them is low, allowing consumers to compensate for their emissions without significant sacrifices. Regarding the distribution of emission reduction responsibilities I argue that excess emissions are permissible if they are offset properly. However, if individuals buy offsets only because they are cheap, they fail to be robustly motivated to choose a permissible course of action.This suspected lack (...) of robust motivation raises both pragmatic questions about the functioning of offsetting schemes and moral questions about the worth of such unstable motives. The analysis provided here also has wider implications for the normative analysis of partial compliance and ‘many hands’ problems, especially for those cases where compliance levels and costs interact. (shrink)

The Tanner Lectures are a collection of educational and scientific discussions relating to human values. Conducted by leaders in their fields, the lectures are presented at prestigious educational facilities around the world.

This chapter concerns the nature of our obligations as individuals when it comes to our emissions-producing activities and climate change. The first half of the chapter argues that the popular ‘expected utility’ approach to this question faces a problematic dilemma: either it gives skeptical verdicts, saying that there are no such obligations, or it yields implausibly strong verdicts. The second half of the chapter diagnoses the problem. It is argued that the dilemma arises from a very general feature of the (...) view, and thus is shared by other views as well. The chapter then discusses what an account of our individual obligations needs to look like if it is to avoid the dilemma. Finally, the discussion is extended beyond climate change to other collective impact contexts. (shrink)

Finite systems of deterministic ordinary nonlinear differential equations may be designed to represent forced dissipative hydrodynamic flow. Solutions of these equations can be identified with trajectories in phase space. For those systems with bounded solutions, it is found that nonperiodic solutions are ordinarily unstable with respect to small modifications, so that slightly differing initial states can evolve into considerably different states. Systems with bounded solutions are shown to possess bounded numerical solutions.A simple system representing cellular convection is solved numerically. All (...) of the solutions are found to be unstable, and almost all of them are nonperiodic.The feasibility of very-long-range weather prediction is examined in the light of these results. (shrink)