There are many views on how to handle tiny probabilities of vast utilities, but all of them are controversial. Some of these views undermine arguments for mainstream longtermist projects and some do not. However, longtermist projects shelter within the herd of ordinary behaviors: It is difficult to find a view that undermines arguments for mainstream longtermist projects without also undermining arguments for behaviors like fastening your seatbelt, voting, or building safer nuclear reactors.
I wrote this sequence all in one go several years ago, funded by CEA. I still stand by it and think it’s an important contribution to the literature, especially for readers who are new to it. (In particular, I think that framing the problem as the problem of how to deal with funnel-shaped action profiles immediately cuts through 85% of the proposed solutions to the problem one typically encounters, and makes it obvious what the costs and benefits of a remaining 10% are.)