The length of a zipped file offers a rough-and-ready estimate of its entropy.

ECONOMIST: Computers and language

He worked his way up through the rough-and-tumble rank-and-file of the former ruling United National Independence Party to the governorship of Lusaka in 1985, where he made his mark as an action man.

BBC: NEWS | Africa | Profile: Zambia's 'King Cobra'

And we can watch the movie in reverse when violence erupts in zones of anarchy, such as the Wild West, failed states and neighborhoods controlled by mafias and street gangs, who can't call 911 or file a lawsuit to resolve their disputes but have to administer their own rough justice.

WSJ: Steven Pinker: Why Violence Is Vanishing