Things usually end slowly

Abstract

It’s sometimes claimed or suggested that if an extinction event were to happen, it would happen very quickly (i.e. days, weeks, months). However, when empires fall or species go extinct, they usually do so very slowly (years, decades, millennia). These base rates  suggest we should have a reasonably strong prior on slow decline when thinking about civilisational collapse and, at more of a stretch, existential risks. This sketch is very rough, and I’d love to see someone work out these base rates, and how they might be changing, more carefully.