What causes riots? That's not a question you would expect to have a simple answer.I have seen the correlation between food prices and social unrest discussed elsewhere a few times over the past several years. But the good folks at Technology Review put together a handy-dandy chart that visually documents that correlation:
But today, Marco Lagi and buddies at the New England Complex Systems Institute in Cambridge, say they've found a single factor that seems to trigger riots around the world.
This single factor is the price of food. Lagi and co say that when it rises above a certain threshold, social unrest sweeps the planet.
The evidence comes from two sources. The first is data gathered by the United Nations that plots the price of food against time, the so-called food price index of the Food and Agriculture Organisation of the UN. The second is the date of riots around the world, whatever their cause. Both these sources are plotted on the same graph above.
This clearly seems to show that when the food price index rises above a certain threshold, the result is trouble around the world.
This isn't rocket science. It stands to reason that people become desperate when food is unobtainable. It's often said that any society is three square meals from anarchy.
But what's interesting about this analysis is that Lagi and co say that high food prices don't necessarily trigger riots themselves, they simply create the conditions in which social unrest can flourish. "These observations are consistent with a hypothesis that high global food prices are a precipitating condition for social unrest," say Lagi and co.
In other words, high food prices lead to a kind of tipping point when almost anything can trigger a riot, like a lighted match in a dry forest.
Lagi's analysis is more sophisticated than most, and does place the price of food in its proper role as, perhaps, an "angst multiplier." It magnifies whatever other reasons for unhappiness exist.
This is an interesting theory that could change the way we view history. To put on my historian's hat for a second, during the Gothic Revolt in 378, the Roman Emperor Valens returned with his army to Constantinople to put down the rebellion. But he first had to deal with riots in Constantinople. The city got most of its food from neighboring Thrace, which was closed off because it was being ravaged by the Goths. Many histories blame the riots on food shortages.
But if Lagi's theory is correct, there was a bigger, underlying reason. And there was: the people of Constantinople hated Valens. He was an uneducated farmer from Pannonia (the Pannonians were generally considered oafs) he was an Arian Christian (considered heretical) and he could not speak Greek. The people of Constantinople had supported Valens' rival Procopius for the imperial throne. Valens had defeated Procopius, but neither the city nor Valens ever forgave and forgot.
Indeed, when Valens left to fight the Goths, he remained so incensed at Constantinople that he threatened to level the city upon his return.
Valens never returned. He was killed at the Battle of Adrianople, August 9, 378 AD.