A paradox for tiny probabilities and enormous values

Nick Beckstead (Open Philanthropy Project) and Teruji Thomas (Global Priorities Institute, Oxford University)

GPI Working Paper No. 7-2021, published in Noûs

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 permit passing up arbitrarily great gains to prevent a tiny increase in risk; non-transitive theories deny the principle that, if A is better than B and B is better than C, then A must be better than C. While non-transitivity has been much discussed, we draw out the costs and benefits of recklessness and timidity when it comes to axiology, decision theory, and moral uncertainty.

Other working papers

Longtermism, aggregation, and catastrophic risk – Emma J. Curran (University of Cambridge)

Advocates of longtermism point out that interventions which focus on improving the prospects of people in the very far future will, in expectation, bring about a significant amount of good. Indeed, in expectation, such long-term interventions bring about far more good than their short-term counterparts. As such, longtermists claim we have compelling moral reason to prefer long-term interventions. …

The unexpected value of the future – Hayden Wilkinson (Global Priorities Institute, University of Oxford)

Various philosophers accept moral views that are impartial, additive, and risk-neutral with respect to betterness. But, if that risk neutrality is spelt out according to expected value theory alone, such views face a dire reductio ad absurdum. If the expected sum of value in humanity’s future is undefined—if, e.g., the probability distribution over possible values of the future resembles the Pasadena game, or a Cauchy distribution—then those views say that no real-world option is ever better than any other. And, as I argue…

When should an effective altruist donate? – William MacAskill (Global Priorities Institute, Oxford University)

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,…