We don't have to imagine scenarios. There have been plenty of disasters in the world; so where are the examples of people being reduced to savages?
more from the original article
(Johann Hari: The myth of the panicking disaster victim in The Independent)

The vast majority of people behave in the aftermath as altruists, saving their fellow human beings and sharing what they have.

The same predictions are made about every disaster – that once the lid of a tightly policed civilization is knocked off for a second, humans will become beasts. But the opposite is the case...

The evidence gathered over centuries of disasters, natural and man-made, is overwhelming. The vast majority of people, when a disaster hits, behave in the aftermath as altruists. They organise spontaneously to save their fellow human beings, to share what they have, and to show kindness. They reveal themselves to be better people than they ever expected.

When the social scientist Enrico Quarantelli tried to write a thesis on how people descend into chaos and panic after disasters, he concluded: "My God! I can't find any instances of it." On the contrary, he wrote, in disasters "the social order does not break down... Co-operative rather than selfish behaviour predominates".
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