The Asymmetry, Uncertainty, and the Long Term

Teruji Thomas (Global Priorities Institute, Oxford University)

GPI Working Paper No. 11-2019, published in Philosophy and Phenomenological Research

The Asymmetry is the view in population ethics that, while we ought to avoid creating additional bad lives, there is no requirement to create additional good ones. The question is how to embed this view in a complete normative theory, and in particular one that treats uncertainty in a plausible way. After reviewing the many difficulties that arise in this area, I present general ‘supervenience principles’ that reduce arbitrary choices to uncertainty-free ones. In that sense they provide a method for aggregating across states of nature. But they also reduce arbitrary choices to one-person cases, and in that sense provide a method for aggregating across people. The principles are general in that they are compatible with total utilitarianism and ex post prioritarianism in fixed-population cases, and with a wide range of ways of extending these views to variable-population cases. I then illustrate these principles by writing down a complete theory of the Asymmetry, or rather several such theories to reflect some of the main substantive choice-points. In doing so I suggest a new way to deal with the intransitivity of the relation ‘ought to choose A over B’. Finally, I consider what these views have to say about the importance of extinction risk and the long-run future.

Please note that this working paper contains some additional material about cyclic choice and also about ʽhardʼ versions of the asymmetry, according to which harms to independently existing people cannot be justified by the creation of good lives. But for other material, please refer to and cite the published version in Philosophy and Phenomelogical Research.

Other working papers

A paradox for tiny probabilities and enormous values – Nick Beckstead (Open Philanthropy Project) and Teruji Thomas (Global Priorities Institute, Oxford University)

We show that every theory of the value of uncertain prospects must have one of three unpalatable properties. Reckless theories recommend risking arbitrarily great gains at arbitrarily long odds for the sake of enormous potential; timid theories recommend passing up arbitrarily great gains to prevent a tiny increase in risk; nontransitive theories deny the principle that, if A is better than B and B is better than C, then A must be better than C.

Do not go gentle: why the Asymmetry does not support anti-natalism – Andreas Mogensen (Global Priorities Institute, Oxford University)

According to the Asymmetry, adding lives that are not worth living to the population makes the outcome pro tanto worse, but adding lives that are well worth living to the population does not make the outcome pro tanto better. It has been argued that the Asymmetry entails the desirability of human extinction. However, this argument rests on a misunderstanding of the kind of neutrality attributed to the addition of lives worth living by the Asymmetry. A similar misunderstanding is shown to underlie Benatar’s case for anti-natalism.

Intergenerational equity under catastrophic climate change – Aurélie Méjean (CNRS, Paris), Antonin Pottier (EHESS, CIRED, Paris), Stéphane Zuber (CNRS, Paris) and Marc Fleurbaey (CNRS, Paris School of Economics)

Climate change raises the issue of intergenerational equity. As climate change threatens irreversible and dangerous impacts, possibly leading to extinction, the most relevant trade-off may not be between present and future consumption, but between present consumption and the mere existence of future generations. To investigate this trade-off, we build an integrated assessment model that explicitly accounts for the risk of extinction of future generations…