"A defining feature of history is that there are many more black swans — not to mention what Didier Sornette calls “dragon kings,” events so large in scale that they lie beyond even a power-law distribution — than a normally distributed world would lead us to expect. All such events lie in the realm of uncertainty, not of calculable risk. Moreover, the world we have built has, over time, become an increasingly complex system prone to all kinds of random behavior, nonlinear relationships and “fat-tailed” distributions. A disaster such as a pandemic is not a single, discrete event. It invariably leads to other forms of disaster — economic, social and political. There can be, and often are, cascades or chain reactions of disaster. The more networked the world becomes, the more we see this."