Tiny probabilities and the value of the far future

Petra Kosonen (Population Wellbeing Initiative, University of Texas at Austin)

GPI Working Paper No. 1-2023

Morally speaking, what matters the most is the far future - at least according to Longtermism. The reason why the far future is of utmost importance is that our acts' expected influence on the value of the world is mainly determined by their consequences in the far future. The case for Longtermism is straightforward: Given the enormous number of people who might exist in the far future, even a tiny probability of affecting how the far future goes outweighs the importance of our acts' consequences in the near term. However, there seems to be something wrong with a theory that lets very small probabilities of huge payoffs dictate one's own course of action. If, instead, we discount very small probabilities to zero, we may have a response to Longtermism provided that its truth depends on tiny probabilities of vast value. Contrary to this, I will argue that discounting small probabilities does not undermine Longtermism.

Other working papers

Cassandra’s Curse: A second tragedy of the commons – Philippe Colo (ETH Zurich)

This paper studies why scientific forecasts regarding exceptional or rare events generally fail to trigger adequate public response. I consider a game of contribution to a public bad. Prior to the game, I assume contributors receive non-verifiable expert advice regarding uncertain damages. In addition, I assume that the expert cares only about social welfare. Under mild assumptions, I show that no information transmission can happen at equilibrium when the number of contributors…