The expected value of extinction risk reduction is positive

byJanBrauner4mo15th Dec 201819 comments


By Jan Brauner and Friederike Grosse-Holz

Work on this article has been funded by the Centre for Effective Altruism, but the article represents the personal views of the authors.

Assume it matters morally what happens in the millions of years to come. What should we do, then? Will efforts to reduce the risk of human extinction lead to a better or worse future?

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If most expected value or disvalue lies in the billions of years to come, altruists should plausibly focus their efforts on improving the long-term future. It is not clear whether reducing the risk of human extinction would, in expectation, improve the long-term future, because a future with humanity may be better or worse than one without it.

From a consequentialist, welfarist view, most expected value (EV) or disvalue of the future comes from scenarios in which (post-)humanity colonizes space, because these scenarios contain most expected beings. Simply extrapolating the current welfare (part 1.1) of humans and farmed and wild animals, it is unclear whether we should support spreading sentient beings to other planets.

From a more general perspective (part 1.2), future agents will likely care morally about the same things we find valuable or about any of the things we are neutral towards. It seems very unlikely that they would see value exactly where we see disvalue. If future agents are powerful enough to shape the world according to their preferences, this asymmetry implies the EV of future agents colonizing space is positive from many welfarist perspectives.

If we can defer the decision about whether to colonize space to future agents with more moral and empirical insight, doing so creates option value (part 1.3). However, most expected future disvalue plausibly comes from futures controlled by indifferent or malicious agents. Such “bad” agents will make worse decisions than we, currently, could. Thus, the option value in reducing the risk of human extinction is small.

The universe may not stay empty, even if humanity goes extinct (part 2.1). A non-human animal civilization, extraterrestrials or uncontrolled artificial intelligence that was created by humanity might colonize space. These scenarios may be worse than (post-)human space colonization in expectation. Additionally, with more moral or empirical insight, we might realize that the universe is already filled with beings or things we care about (part 2.2). If the universe is already filled with disvalue that future agents could alleviate, this gives further reason to reduce extinction risk.

In practice, many efforts to reduce the risk of human extinction also have other effects of long-term significance. Such efforts might often reduce the risk of global catastrophes (part 3.1) from which humanity would recover, but which might set technological and social progress on a worse track than they are on now. Furthermore, such efforts often promote global coordination, peace and stability (part 3.2), which is crucial for safe development of pivotal technologies and to avoid negative trajectory changes in general.

Aggregating these considerations, efforts to reduce extinction risk seem positive in expectation from most consequentialist views, ranging from neutral on some views to extremely positive on others. As efforts to reduce extinction risk also seem highly leveraged and time-sensitive, they should probably hold prominent place in the long-termist EA portfolio.