"Occasionally they came to villages, and at each village they encountered a roadblock of fallen trees. Having had centuries of experience with the smallpox virus, the village elders had instituted their own methods for controlling the virus, according to their received wisdom, which was to cut their villages off from the world, to protect their people from a raging plague. It was reverse quarantine, an ancient practice in Africa, where a village bars itself from strangers during a time of disease, and drives away outsiders who appear. (94)"

Next Quote

Western societies from ancient Athens to imperial Rome to the French republic rarely collapsed because of a shortage of resources or because foreign enemies proved too numerous or formidable in arms - even when those enemies were grim Macedonians or Germans. Rather, in times of peace and prosperity there arose an unreal view of the world beyond their borders, one that was the product of insularity brought about by success, and an intellectual arrogance that for some can be the unfortunate byproduct of an enlightened society.

— Victor Davis Hanson