Beliefs about the end of humanity: How bad, likely, and important is human extinction?

Matthew Coleman (Northeastern University), Lucius Caviola (Global Priorities Institute, University of Oxford), Joshua Lewis (New York University) and Geoffrey Goodwin (University of Pennsylvania)

GPI Working Paper No. 1-2024

Human extinction would mean the end of humanity’s achievements, culture, and future potential. According to some ethical views, this would be a terrible outcome. But how do people think about human extinction? And how much do they prioritize preventing extinction over other societal issues? Across five empirical studies (N = 2,147; U.S. and China) we find that people consider extinction prevention a societal priority and deserving of greatly increased societal resources. However, despite estimating the likelihood of human extinction to be 5% this century (U.S. median), people believe that the chances would need to be around 30% for it to be the very highest priority. In line with this, people consider extinction prevention to be only one among several important societal issues. People’s judgments about the relative importance of extinction prevention appear relatively fixed and hard to change by reason-based interventions.

Other working papers

Critical-set views, biographical identity, and the long term – Elliott Thornley (Global Priorities Institute, University of Oxford)

Critical-set views avoid the Repugnant Conclusion by subtracting some constant from the welfare score of each life in a population. These views are thus sensitive to facts about biographical identity: identity between lives. In this paper, I argue that questions of biographical identity give us reason to reject critical-set views and embrace the total view. I end with a practical implication. If we shift our credences towards the total view, we should also shift our efforts towards ensuring that humanity survives for the long term.

Non-additive axiologies in large worlds – Christian Tarsney and Teruji Thomas (Global Priorities Institute, Oxford University)

Is the overall value of a world just the sum of values contributed by each value-bearing entity in that world? Additively separable axiologies (like total utilitarianism, prioritarianism, and critical level views) say ‘yes’, but non-additive axiologies (like average utilitarianism, rank-discounted utilitarianism, and variable value views) say ‘no’…

Tiny probabilities and the value of the far future – Petra Kosonen (Population Wellbeing Initiative, University of Texas at Austin)

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…