In talking with people about the long-term future, I've found it to be extremely helpful to give an estimate for the percent chance humanity goes extinct by 2100 (or in 100 years). Right now, I say ~10% or 5-19%, and then say something like "it would be really nice if we could get that number below 1%". My estimate is taken from these sources:
- FHI's casual 2008 survey of various x-risks. Taken together, they give a 19% chance by 2100.
- The 2007 Stern Review, a 700-page report on climate change. It uses 0.1% as an upper bound modeling assumption for annual extinction risk, which means 9.5% in the next 100 years (by 2107).
- This July 2018 Vox article from Liv Boeree that references the FHI study and also says "5 to 19 percent chance of complete human extinction by the end of this century". (I'm not sure where the 5% comes from?)
- This 2016 report on GCRs from FHI and the Global Priorities Project. They reference the two sources above and just say it's hard to create a reasonable estimate.
However, I find the strength of these estimates pretty weak. If someone were to ask me to "back up" my 10% number, the best I'd have is an informal survey circulated at an x-risk conference in 2008. So, a couple questions:
- Are there other sources that I'm missing?
- Do others also feel like it would be helpful to have an updated/more rigorous estimate here? (Or is it not actually helpful to operate at this level of abstraction? i.e. Should we concentrate just on individual sources of x-risk instead?)
- Is it even possible to create an estimate like this? Or is the range of uncertainty just too large, that we'd need to give an estimate like 2-59%? (Clearly, this gets more difficult the longer we try to project out. But can't we estimate it for 2050, 2075, or 2100?)
Thanks for your thoughts and help!
Incidentally, CSER's Simon Beard has a working paper just up looking at sources of evidence for probability assessments of difference Xrisks and GCRs, and the underlying methodologies. It may be useful for people thinking about the topic of this post (I also imagine he'd be pleased to get comments, as this will go to a peer reviewed publication in due course). http://eprints.lse.ac.uk/89506/1/Beard_Existential-Risk-Assessments_Accepted.pdf
We are indeed keen to get comments and feedback. Also note that the final 1/3rd or so of the paper is an extensive catalogue of assessments of the probability of different risks in which we try to incorporate all the sources we could find (though we are very happy if others know of more of these).
I will say however that the overwhelming sense I got in doing this study is that it is sometimes best not to put this kind of number on risks.