TL;DR are there any forum posts or similarly accessible writing that clarify different notions of x-risk? If not, does it seem worth writing?
My impression is that prevailing notions of x-risk (i.e. what it means, not specific cause areas) have broadened or shifted over time, but there's a lack of clarity about what notion/definition people are basing arguments on in discourse.
At the same time, discussion of x-risk sometimes seems too narrow. For example, in the most recent 80K podcast with Will MacAskill, they at one point talk about x-risk in terms of literal 100% human annihilation. IMO this is one of the least relevant notions of x-risk, for cause prioritisation purposes. Perhaps there's a bias because literal human extinction is the most concrete/easy to explain/easy to reason about? Nowadays I frame longtermist cause prioritisation more like "what could cause the largest losses to the expected value of the future" than "what could plausibly annihilate humanity".
Bostrom (2002) defined x-risk as "one where an adverse outcome would either annihilate Earth-originating intelligent life or permanently and drastically curtail its potential". There is also a taxonomy in section 3 of the paper. Torres (2019) explains and analyses five different definitions of x-risk, which I think all have some merit.
To be clear I think many people have internalised broader notions of x-risk in their thoughts and arguments, both generally and for specific cause areas. I just think it could use some clarification and a call for people to clarify themselves, e.g. in a forum post.
This is some advice I wrote about doing back-of-the-envelope calculations (BOTECs) and uncertainty estimation, which are often useful as part of forecasting. This advice isn’t supposed to be a comprehensive guide by any means. The advice originated from specific questions that someone I was mentoring asked me. Note that I’m still fairly inexperienced with forecasting. If you’re someone with experience in forecasting, uncertainty estimation, or BOTECs, I’d love to hear how you would expand or deviate from this advice.