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Very often we're uncertain about what we ought, morally, to do. We don't know how to weigh the interests of animals against humans, how strong our duties are to improve the lives of distant strangers, or how to think about the ethics of bringing new people into existence. But we still need to act. So how should we make decisions in the face of such uncertainty?

Though economists and philosophers have extensively studied the issue of decision-making in the face of uncertainty about matters of fact, the question of decision-making given fundamental moral uncertainty has been neglected. Philosophers William MacAskill, Krister Bykvist, and Toby Ord try to fill this gap. Moral Uncertainty argues that there are distinctive norms that govern how one ought to make decisions. It defends an information-sensitive account of how to make such decisions by developing an analogy between moral uncertainty and social choice, arguing that the correct way to act in the face of moral uncertainty depends on whether the moral theories in which one has credence are merely ordinal, cardinal, or both cardinal and intertheoretically comparable. It tackles the problem of how to make intertheoretical comparisons, discussing potential solutions and the implications of their view for metaethics and practical ethics.

About the Author:
William MacAskill, Associate Professor of Philosophy, University of Oxford, Krister Bykvist, Professor in Practical Philosophy, Stockholm University, Toby Ord, Research Fellow, Future of Humanity Institute, University of Oxford

William MacAskill is an Associate Professor of Philosophy at Oxford University. He has published in philosophy journals such as Mind, Ethics, and the Journal of Philosophy, and has authored the bestselling book Doing Good Better (Avery, 2015). He cofounded the international non-profits Centre for Effective Altruism; 80,000 Hours; and Giving What We Can.

Krister Bykvist is a Professor in Practical Philosophy at Stockholm University and a Research Fellow at the Institute for Future Studies, Stockholm. His articles have appeared in Economics and Philosophy, Philosophical Studies, and the Australasian Journal of Philosophy. His research concerns questions about our responsibility for future generations, the foundations of consequentialism, evaluative uncertainty, and the relationship between preferences, value, and welfare. He is currently leading the Valuing Future Lives project.

Toby Ord is a Research Fellow at the Future of Humanity Institute, University of Oxford. His research concerns some of the key questions facing humanity, identifying what the most important issues of our time are and how we can best address them. His research previously focused on the ethics of global health and global poverty, and he is the creator of Giving What We Can, an international society focusing on pledging to the most effective charities. He is also the co-founder of the Effective Altruism movement.