Steven Johnson’s latest book, The Ghost Map, tells the story of two Londoners whose map of a cholera outbreak helped to virtually eradicate the disease. Johnson spoke to Ben Mathis-Lilley about what the sewers of Olde London can tell us about the urban world of tomorrow.
How did you become interested in this case?
I’d known about the story for a long time, and I had been thinking after 9/11 about the risks associated with dense urban settlements. In 1854, when an epidemic could kill 10 percent of a neighborhood in five days, a lot of people quite reasonably thought London would shrink and no one would build cities that big anymore.
But density helped stop epidemics, too?
Right. What this doctor named John Snow did was create a map that showed deaths radiating out from one pump, so you could see cholera was in the water, which almost no one at the time believed. But the assistant curate at the local parish, not a man of science, also played a central role in the creation of the map; he had all the on-the-ground neighborhood expertise needed to figure out who had or hadn’t drunk from this contaminated pump.
It sounds like crime-solving on The Wire.
The Wire is a great way of thinking about this. The Wire is in many ways a sequel to the way that Dickens thought about the city—it works across the many scales of city life.
But can new, improved information-sharing technology be put to a greater social good than MySpace?
311 is the best urban information management tool in a long time. During the blackout, 311 got a lot of calls from diabetics asking how long insulin could last in a refrigerator without power. The city had no idea that that was going to be a concern—but within a couple hours Bloomberg got the answer and discussed it in his radio speech.
Doesn’t technology also help people spread, or even create, an epidemic?
Yes, but our understanding of genetics is advancing at a rate much faster than the diseases themselves. The most telling example is avian flu, which can’t yet spread rapidly between human hosts. It’s remarkable: There’s been billions of dollars spent planning for a disease which doesn’t even exist yet. In 20 or 30 years, we might be able to create vaccines immediately, and the idea of epidemics won’t keep us up at night.
Does global warming keep you up at night?
That might actually encourage us to urbanize more. In cities, people expend fewer resources on heating and cooling; they use mass transit. Even if global warming becomes catastrophic, we would probably still live in cities, though we might have to move some of them.
The Ghost Map
Riverhead. 320 pages.