Longtermism in an Infinite World

Christian J. Tarsney (Population Wellbeing Initiative, University of Texas at Austin) and Hayden Wilkinson (Global Priorities Institute, University of Oxford)

GPI Working Paper No. 4-2023, forthcoming in Essays on Longtermism

The case for longtermism depends on the vast potential scale of the future. But that same vastness also threatens to undermine the case for longtermism: If the future contains infinite value, then many theories of value that support longtermism (e.g., risk-neutral total utilitarianism) seem to imply that no available action is better than any other. And some strategies for avoiding this conclusion (e.g., exponential time discounting) yield views that are much less supportive of longtermism. This chapter explores how the potential infinitude of the future affects the case for longtermism. We argue that (i) there are reasonable prospects for extending risk- neutral totalism and similar views to infinite contexts and (ii) many such extension strategies still support standard arguments for longtermism, since they imply that when we can only affect (or only predictably affect) a finite part of an infinite universe, we can reason as if only that finite part existed. On the other hand, (iii) there are improbable but not impossible physical scenarios in which our actions can have infinite predictable effects on the far future, and these scenarios create substantial unresolved problems for both infinite ethics and the case for longtermism.

Other working papers

Economic inequality and the long-term future – Andreas T. Schmidt (University of Groningen) and Daan Juijn (CE Delft)

Why, if at all, should we object to economic inequality? Some central arguments – the argument from decreasing marginal utility for example – invoke instrumental reasons and object to inequality because of its effects…

Prediction: The long and the short of it – Antony Millner (University of California, Santa Barbara) and Daniel Heyen (ETH Zurich)

Commentators often lament forecasters’ inability to provide precise predictions of the long-run behaviour of complex economic and physical systems. Yet their concerns often conflate the presence of substantial long-run uncertainty with the need for long-run predictability; short-run predictions can partially substitute for long-run predictions if decision-makers can adjust their activities over time. …

A non-identity dilemma for person-affecting views – Elliott Thornley (Global Priorities Institute, University of Oxford)

Person-affecting views in population ethics state that (in cases where all else is equal) we’re permitted but not required to create people who would enjoy good lives. In this paper, I present an argument against every possible variety of person- affecting view. The argument takes the form of a dilemma. Narrow person-affecting views must embrace at least one of three implausible verdicts in a case that I call ‘Expanded Non- Identity.’ Wide person-affecting views run into trouble in a case that I call ‘Two-Shot Non-Identity.’ …