This essay evolved from my keynote address for the plenary session of the ASEAN Conference for Young Scientists 2019 organized by the ASEAN Secretariat, Vietnam Ministry of Science and Technology—whose main theme is sustainability science—organized at Hanoi-based Phenikaa University. It has also benefited from my advisory work for the International Union for Conservation of Nature (IUCN).

Suppose you want to do as much good as possible. What should you do? According to members of the effective altruism movement—which has produced much of the thinking on this issue and counts several moral philosophers as its key protagonists—we should prioritise among the world’s problems by assessing their scale, solvability, and neglectedness. Once we’ve done this, the three top priorities, not necessarily in this order, are (1) aiding the world’s poorest people by providing life-saving medical treatments or alleviating poverty (...) itself, (2) preventing global catastrophic risks, such as those posed by nuclear war or rogue artificial intelligence, and (3) ending factory farming. These claims are both plausible and striking. If correct, they should prompt a stark revision of how we approach our altruistic activities. However, the project of determining how to do the most good—as opposed to say, whether we should do the most good—has only recently, within the last ten years, become the subject of serious academic attention. Many key claims have not yet been carefully scrutinised. This is a cause for concern: are effective altruists doing good badly? In this thesis, I critique and develop some of the latest claims about how individuals can do the most good. I do this in three areas: the value of saving lives (preventing premature deaths), how best to improve lives (making people happier during their lives), and cause prioritisation methodology (frameworks for determining which problems are the highest priorities). In each case, I raise novel theoretical considerations that, when incorporated, change the analysis. Roughly speaking, my main conclusions are (1) saving lives is not as straightforwardly good we tend to suppose, may not be good at all, and is not clearly a priority; (2) happiness can be measured through self-reports and, based on the self-reported evidence, treating mental health stands out as an overlooked problem that may be an even more cost-effective way to improve lives than alleviating poverty; (3) the cause prioritisation methodology proposed by effective altruists needs to be moderately reconceptualised and, when it is, it turns out it is not as illuminating a tool as we might have thought and hoped. (shrink)

It has been argued in some recent work that there are many cases in which individuals are subject toconditional obligationsto give to more effective rather than less effective charities, despite not being unconditionally obligated to give. These conditional obligations, it has been suggested, can allow effective altruists (EAs) to make the central claims about the ethics of charitable giving that characterize the movement without taking any particular position on morality's demandingness. I argue that the range of cases involving charitable giving (...) in which individuals are subject to conditional effectiveness obligations is in fact quite narrow. Because of this, I claim, EAs must endorse the view that well off people have at least fairly demanding unconditional obligations. (shrink)