Intergenerational equity under catastrophic climate change
Aurélie Méjean (CNRS, Paris), Antonin Pottier (Centre d’Economie de la Sorbonne), Stéphane Zuber (Paris School of Economics - CNRS) and Marc Fleurbaey (Princeton University)
GPI Working Paper No. 5-2020, published in Climatic Change
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. We compare different climate policies, which change the probability of catastrophic outcomes yielding an early extinction, within the class of variable population utilitarian social welfare functions. We show that the risk of extinction is the main driver of the preferred policy over climate damages. We analyze the role of inequality aversion and population ethics. Usually a preference for large populations and a low inequality aversion favour the most ambitious climate policy, although there are cases where the effect of inequality aversion is reversed.
Other working papers
Estimating long-term treatment effects without long-term outcome data – David Rhys Bernard (Rethink Priorities), Jojo Lee and Victor Yaneng Wang (Global Priorities Institute, University of Oxford)
The surrogate index method allows policymakers to estimate long-run treatment effects before long-run outcomes are observable. We meta-analyse this approach over nine long-run RCTs in development economics, comparing surrogate estimates to estimates from actual long-run RCT outcomes. We introduce the M-lasso algorithm for constructing the surrogate approach’s first-stage predictive model and compare its performance with other surrogate estimation methods. …
A bargaining-theoretic approach to moral uncertainty – Owen Cotton-Barratt (Future of Humanity Institute, Oxford University), Hilary Greaves (Global Priorities Institute, Oxford University)
This paper explores a new approach to the problem of decision under relevant moral uncertainty. We treat the case of an agent making decisions in the face of moral uncertainty on the model of bargaining theory, as if the decision-making process were one of bargaining among different internal parts of the agent, with different parts committed to different moral theories. The resulting approach contrasts interestingly with the extant “maximise expected choiceworthiness”…
Should longtermists recommend hastening extinction rather than delaying it? – Richard Pettigrew (University of Bristol)
Longtermism is the view that the most urgent global priorities, and those to which we should devote the largest portion of our current resources, are those that focus on ensuring a long future for humanity, and perhaps sentient or intelligent life more generally, and improving the quality of those lives in that long future. The central argument for this conclusion is that, given a fixed amount of are source that we are able to devote to global priorities, the longtermist’s favoured interventions have…