As an interesting exercise, and in response to the many in the media and otherwise who are calling for Brexit to be a trigger for the end of civilization, Ian Morris at Stratfor looks at historical episodes of dark ages (as that’s what follows a breakdown in civilization), and identifies five features/causal factors that are always present:
1) Mass migration
2) Disease
3) State failure
4) Collapse of trade
5) Climate change
The presence of these factors all at once does not guarantee collapse, but they are a necessary condition. It is also worth noting that not all of them are currently present in a meaningful way. But it is an interesting list to keep in mind when analyzing the state of the world.