William MacAskill

_An Introduction to Utilitarianism: From Theory to Practice _is a state-of-the-art text, simultaneously accessible to introductory students and informative for more advanced readers. Two key features set it apart. First, its comprehensive coverage of the arguments for and against utilitarianism is unparalleled. Second, it takes seriously the practical implications of utilitarianism for _how we should live_, with a particular emphasis on utilitarianism's _impartial beneficence_ and its focus on _effectiveness_. Guided by the conviction that practical ethics is more about how best to use our limited time and resources than which victims to hit with trolleys in thought experiments, its practical upshots should prove amenable to utilitarians and non-utilitarians alike.

The term “effective altruism” has no official definition, meaning that different authors will inevitably understand the term in different ways. Since this harbours the potential for considerable confusion, William MacAskill, one of the leaders of the effective altruism movement, has contributed a chapter aimed at forestalling some of these potential confusions. In this chapter, MacAskill first outlines a brief history of the effective altruism movement. He then proposes his preferred definition of “effective altruism”, aiming to capture the central activities and concerns of those most deeply involved in the movement. Finally, he replies to various common misconceptions about the movement. These include the views that effective altruism is just utilitarianism, that it is purely about poverty alleviation, that it is purely about donations, and that it in principle ignores possibilities for systemic change.

In the final pages of _On What Matters_, Volume II, Derek Parfit comments: “We live during the hinge of history…If we acit wisely in the next few centuries, humanity will survive its most dangerous and decisive period…What now matters most is that we avoid ending human history.” This passage echoes Parfit’s comment, in _Reasons and Persons_, that “the next few centuries will be the most important in human history”. But is the claim that we live at the hinge of history true? The argument of this chapter is that it is not. The chapter first suggests a way of making the hinge of history claim precise and action-relevant in the context of the question of whether altruists should try to do good now, or invest their resources in order to have more of an impact later on. It then canvasses arguments for and against the hinge of history claim, and suggests that, though we certainly live at an unusual time, we don’t have sufficient evidence to think that the present is the most influential time ever.

Peter Singer argues that middle-class members of affluent countries have an obligation to give away almost all their income to fight poverty in the developing world. Others, however, argue that this view is _too demanding_: it is asking more of us than morality truly requires. This chapter proposes a weaker principle, the very weak principle of sacrifice: Most middle-class members of affluent countries ought, morally, to use at least 10 percent of their income to effectively improve the lives of others. This principle is not very demanding at all, and therefore the “demandingness” objection has not even pro tanto force against it.

An Oxford philosopher argues that solving today's problems might require putting future generations ahead of ourselves The human story is just beginning. There are five thousand years of written history, but perhaps millions more to come. In What We Owe the Future, philosopher William MacAskill develops a perspective he calls longtermism to argue that this fact is of enormous moral importance. While we are comfortable thinking about the equal moral worth of humans alive today, we haven't considered the moral weight of future generations. We have put them at grave risk, and not just with climate change. AI could lock humans into perpetual dystopia, or pandemics could end us. But the future could be wonderful: moral and technological progress could result in unimaginable human flourishing. The future is in our hands. As MacAskill shows, we can make the world better for billions of years to come. Perhaps even more importantly, he shows us just how much is at stake if we consign future generations to oblivion.

An Introduction to Utilitarianism: From Theory to Practice is a state-of-the-art text, simultaneously accessible to introductory students and informative for more advanced readers. Two key features set it apart. First, its comprehensive coverage of the arguments for and against utilitarianism is unparalleled. Second, it takes seriously the practical implications of utilitarianism for how we should live, with a particular emphasis on utilitarianism's impartial beneficence and its focus on effectiveness. Guided by the conviction that practical ethics is more about how best to use our limited time and resources than which victims to hit with trolleys in thought experiments, its practical upshots should prove amenable to utilitarians and non-utilitarians alike.

True benevolence is, most fundamentally, a desire that the world be better. It is natural and common, however, to frame thinking about benevolence indirectly, in terms of a desire to make a difference to how good the world is. This would be an innocuous shift if desires to make a difference were extensionally equivalent to desires that the world be better. This paper shows that at least on some common ways of making a “desire to make a difference” precise, this extensional equivalence fails. Where it fails, “difference-making preferences” run counter to the ideals of benevolence. In particular, in the context of decision making under uncertainty, coupling a “difference-making” framing in a natural way with risk aversion leads to preferences that violate stochastic dominance, and that lead to a strong form of collective defeat, from the point of view of betterness. Difference-making framings and true benevolence are not strictly mutually inconsistent, but agents seeking to implement true benevolence must take care to avoid the various pitfalls that we outline.

In the final pages of On What Matters, Volume II, Derek Parfit comments: ‘We live during the hinge of history... If we act wisely in the next few centuries, humanity will survive its most dangerous and decisive period... What now matters most is that we avoid ending human history.’ This passage echoes Parfit's comment, in Reasons and Persons, that ‘the next few centuries will be the most important in human history’. But is the claim that we live at the hinge of history true? The argument of this paper is that it is not. The paper first suggests a way of making the hinge of history claim precise and action-relevant in the context of the question of whether altruists should try to do good now, or invest their resources in order to have more of an impact later on. Given this understanding, there are two worldviews - the Time of Perils and Value Lock-in views - on which we are indeed living during, or about to enter, the hinge of history. This paper then presents two arguments against the hinge of history claim: first, that it is a priori extremely unlikely to be true, and that the evidence in its favour is not strong enough to overcome this a priori unlikelihood; second, an inductive argument that our ability to influence events has been increasing over time, and we should expect that trend to continue into the future. The paper concludes by considering two additional arguments in favour of the claim, and suggests that though they have some merit, they are not sufficient for us to think that the present time is the most important time in the history of civilisation. GPI Working Paper No. 12-2020

Given plausible assumptions about the long-run impact of our everyday actions, we show that standard non-consequentialist constraints on doing harm entail that we should try to do as little as possible in our lives. 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. GPI Working Paper No. 6-2019.

Effective altruism is the use of evidence and careful reasoning to work out how to maximize positive impact on others with a given unit of resources, and the taking of action on that basis. It’s a philosophy and a social movement that is gaining considerable steam in the philanthropic world. For example, GiveWell, an organization that recommends charities working in global health and development and generally follows effective altruist principles, moves over $90 million per year to its top recommendations. Giving What We Can, which encourages individuals to pledge at least 10% of their income to the most cost-effective charities, now has over 3500 members, together pledging over $1.5 billion of lifetime donations. Good Ventures is a foundation, founded by Dustin Moskovitz and Cari Tuna, that is committed to effective altruist principles; it has potential assets of $11 billion, and is distributing over $200 million each year in grants, advised by the Open Philanthropy Project. [...] GPI Working Paper No. 8-2019

True benevolence is, most fundamentally, a desire that the world be better. It is natural and common, however, to frame thinking about benevolence indirectly, in terms of a desire to make a difference to how good the world is. This would be an innocuous shift if desires to make a difference were extensionally equivalent to desires that the world be better. This paper shows that at least on some common ways of making a “desire to make a difference” precise, this extensional equivalence fails. Where it fails, “difference-making preferences” run counter to the ideals of benevolence. In particular, in the context of decision making under uncertainty, coupling a “difference-making” framing in a natural way with risk aversion leads to preferences that violate stochastic dominance, and that lead to a strong form of collective defeat, from the point of view of betterness. Difference-making framings and true benevolence are not strictly mutually inconsistent, but agents seeking to implement true benevolence must take care to avoid the various pitfalls that we outline. GPI Working Paper No. 16-2022

This chapter makes the case for strong longtermism: the claim that, in many situations, impact on the long-run future is the most important feature of our actions. Our case begins with the observation that an astronomical number of people could exist in the aeons to come. Even on conservative estimates, the expected future population is enormous. We then add a moral claim: all the consequences of our actions matter. In particular, the moral importance of what happens does not depend on when it happens. That pushes us toward strong longtermism. We then address a few potential concerns, the first of which is that it is impossible to have any sufficiently predictable influence on the course of the long-run future. We argue that this is not true. Some actions can reasonably be expected to improve humanity’s long-term prospects. These include reducing the risk of human extinction, preventing climate change, guiding the development of artificial intelligence, and investing funds for later use. We end by arguing that these actions are more than just extremely effective ways to do good. Since the benefits of longtermist efforts are large and the personal costs are comparatively small, we are morally required to take up these efforts.

Suppose that an altruistic agent who is uncertain between evidential and causal decision theory finds herself in a situation where these theories give conflicting verdicts. We argue that even if she has significantly higher credence in CDT, she should nevertheless act in accordance with EDT. First, we claim that the appropriate response to normative uncertainty is to hedge one's bets. That is, if the stakes are much higher on one theory than another, and the credences you assign to each of these theories are not very different, then it is appropriate to choose the option that performs best on the high-stakes theory. Second, we show that, given the assumption of altruism, the existence of correlated decision makers will increase the stakes for EDT but leave the stakes for CDT unaffected. Together these two claims imply that whenever there are sufficiently many correlated agents, the appropriate response is to act in accordance with EDT.

It has been argued that evolutionary considerations favour utilitarianism by selectively debunking its competitors. However, evolutionary considerations also seem to undermine the practical significance of utilitarianism, since commonsense beliefs about well-being seem like prime candidates for evolutionary debunking. We argue that the practical significance of utilitarianism is not undermined in this way if we understand the requirements of practical rationality as sensitive to normative uncertainty. We consider the view that rational decision-making under normative uncertainty requires maximizing expected choice-worthiness, as well as the possibility that different theories’ choice-worthiness rankings are not all interval-scale measurable or intertheoretically comparable. Finally, we suggest how evolutionary considerations may increase the practical significance of utilitarianism even if belief in utilitarianism is debunked by evolutionary considerations, so long as belief in competing theories is undermined to an even greater extent.

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.

In all probability, future generations will outnumber us by thousands or millions to one. In the aggregate, their interests therefore matter enormously, and anything we can do to steer the future of civilization onto a better trajectory is of tremendous moral importance. This is the guiding thought that defines the philosophy of longtermism. Political science tells us that the practices of most governments are at stark odds with longtermism. But the problems of political short-termism are neither necessary nor inevitable. In principle, the state could serve as a powerful tool for positively shaping the long-term future. In this chapter, we make some suggestions about how to align government incentives with the interests of future generations. First, in Section II, we explain the root causes of political short-termism. Then, in Section III, we propose and defend four institutional reforms that we think would be promising ways to increase the time horizons of governments: 1) government research institutions and archivists; 2) posterity impact assessments; 3) futures assemblies; and 4) legislative houses for future generations. Section IV concludes with five additional reforms that are promising but require further research: to fully resolve the problem of political short-termism we must develop a comprehensive research program on effective longtermist political institutions.

Effective altruism is the use of evidence and reason to figure out how to benefit others as much as possible and the taking of action on that basis. This chapter discusses the moral framework and methodological approach that effective altruism uses to prioritize causes, charities, and careers, and examines some of the world problems that, on this perspective, appear to be most urgent and important: global health and development, non-human animal suffering, and risks to long-term human survival. It then lays out some of the most important unsolved problems facing the effective altruist project.

A major problem for interpersonal aggregation is how to compare utility across individuals; a major problem for decision-making under normative uncertainty is the formally analogous problem of how to compare choice-worthiness across theories. We introduce and study a class of methods, which we call statistical normalization methods, for making interpersonal comparisons of utility and intertheoretic comparisons of choice-worthiness. We argue against the statistical normalization methods that have been proposed in the literature. We argue, instead, in favor of normalization of variance: we claim that this is the account that most plausibly gives all individuals or theories ‘equal say’. To this end, we provide two proofs that variance normalization has desirable properties that all other normalization methods lack, though we also show how different assumptions could lead one to axiomatize alternative statistical normalization methods.

This paper argues in favor of a particular account of decision‐making under normative uncertainty: that, when it is possible to do so, one should maximize expected choice‐worthiness. Though this position has been often suggested in the literature and is often taken to be the ‘default’ view, it has so far received little in the way of positive argument in its favor. After dealing with some preliminaries and giving the basic motivation for taking normative uncertainty into account in our decision‐making, we consider and provide new arguments against two rival accounts that have been offered—the accounts that we call ‘My Favorite Theory’ and ‘My Favorite Option’. We then give a novel argument for comparativism—the view that, under normative uncertainty, one should take into account both probabilities of different theories and magnitudes of choice‐worthiness. Finally, we further argue in favor of maximizing expected choice‐worthiness and consider and respond to five objections.

In the article, ‘Being Good in a World of Need: Some Empirical Worries and an Uncomfortable Philosophical Possibility,’ Larry Temkin presents some concerns about the possible impact of international aid on the poorest people in the world, suggesting that the nature of the duties of beneficence of the global rich to the global poor are much more murky than some people have made out. In this article, I’ll respond to Temkin from the perspective of effective altruism—one of the targets he attacks. I’ll argue that Temkin’s critique has little empirical justification, given the conclusions he wants to reach, and is therefore impotent.

A number of philosophers have claimed that we should take not just empirical uncertainty but also fundamental moral uncertainty into account in our decision-making, and that, despite widespread moral disagreement, doing so would allow us to draw robust lessons for some issues in practical ethics. In this article, I argue that, so far, the implications for practical ethics have been drawn too simplistically. First, the implications of moral uncertainty for normative ethics are far more wide-ranging than has been noted so far. Second, one can't straightforwardly argue from moral uncertainty to particular conclusions in practical ethics, both because of ‘interaction’ effects between moral issues, and because of the variety of different possible intertheoretic comparisons that one can reasonably endorse.