The Ghost Map: The Story of London's Most Terrifying Epidemic—and How It Changed Science, Cities, and the Modern World
by Steven Johnson
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Below are the most popular and impactful highlights and quotes from The Ghost Map: The Story of London's Most Terrifying Epidemic—and How It Changed Science, Cities, and the Modern World:
This is how great intellectual breakthroughs usually happen in practice. It is rarely the isolated genius having a eureka moment alone in the lab. Nor is it merely a question of building on precedent, of standing on the shoulders of giants, in Newton's famous phrase. Great breakthroughs are closer to what happens in a flood plain: a dozen separate tributaries converge, and the rising waters lift the genius high enough that he or she can see around the conceptual obstructions of the age.
How could so many intelligent people be so grievously wrong for such an extended period of time? How could they ignore so much overwhelming evidence that contradicted their most basic theories? These questions, too, deserve their own discipline: the sociology of error.
But epidemics create a kind of history from below: they can be world-changing, but the participants are almost inevitably ordinary folk, following their established routines, not thinking for a second about how their actions will be recorded for posterity.
Superstition, then and now, is not just a threat to the truth. It’s also a threat to national security.
The first is to embrace—as a matter of philosophy and public policy—the insights of science, in particular the fields that descend from the great Darwinian revolution that began only a matter of years after Snow’s death: genetics, evolutionary theory, environmental science. Our safety depends on being able to predict the evolutionary path that viruses and bacteria will take in the coming decades, just as safety in Snow’s day depended on the rational application of the scientific method to public-health matters. Superstition, then and now, is not just a threat to the truth. It’s also a threat to national security.
Dense urban environments may do away with nature altogether—there are many vibrantly healthy neighborhoods in Paris or Manhattan that lack even a single tree—but they also perform the crucial service of reducing mankind’s environmental footprint. Compare the sewage system of a midsized city like Portland, Oregon, with the kind of waste management resources that would be required to support the same population dispersed across the countryside. Portland’s 500,000 inhabitants require two sewage treatment plants, connected by 2,000 miles of pipes. A rural population would require more than 100,000 septic tanks, and 7,000 miles of pipe. The rural waste system would be several times more expensive than the urban version.
It is a great testimony to the connectedness of life on earth that the fates of the largest and the tiniest life should be so closely dependent on each other.
But Engels and Dickens suggested a new twist: that the advance of civilization produced barbarity as an unavoidable waste product, as essential to its metabolism as the gleaming spires and cultivated thought of polite society. The barbarians weren’t storming the gates.
The history of knowledge conventionally focuses on breakthrough ideas and conceptual leaps. But the blind spots on the map, the dark continents of error and prejudice, carry their own mystery as well. How could so many intelligent people be so grievously wrong for such an extended period of time? How could they ignore so much overwhelming evidence that contradicted their most basic theories? These questions, too, deserve their own discipline—the sociology of error.
And of course, if they do recognize that they are living through a historical crisis, it’s often too late—because, like it or not, the primary way that ordinary people create this distinct genre of history is by dying.
The timing of Thomas Lewis’ illness suggests one chilling alternative history. The Broad Street outbreak had subsided in part because the only viable route between the well and the neighborhood’s small intestines had run through the cesspool at 40 Broad. When baby Lewis died, the connection had died with it. But when her husband fell ill, Sarah Lewis began emptying the buckets of soiled water in the cesspool all over again. If Snow had not persuaded the Board of Governors to remove the handle when he did, the disease might have torn through the neighborhood all over again, the well water restocked with a fresh supply of V. cholerae. And so Snow’s intervention did not just help bring the outbreak to a close. It also prevented a second attack.
All nucleated organisms generate excess calcium as a waste product. Since at least the Cambrian times, organisms have accumulated those calcium reserves, and put them to good use: building shells, teeth, skeletons. Your ability to walk upright is due to evolution’s knack for recycling its toxic waste.
Right now we’re in an arms race with the microbes, because, effectively, we’re operating on the same scale that they are. The viruses are both our enemy and our arms manufacturer.
This is not mere sentimentality. The triumph of twentieth-century metropolitan life is, in a real sense, the triumph of one image over the other: the dark ritual of deadly epidemics replaced by the convivial exchanges of strangers from different backgrounds sharing ideas on the sidewalk.
In the long run, the map was a triumph of marketing as much as empirical science. It helped a good idea find a wide audience.
They mistook the smoke for the fire.
The observers of the time were detecting a phenomenon that we now largely take for granted: that "mass" behavior can often diverge strikingly from the desires of the individuals that make up the mass.
DR. JOHN SNOW—This well-known physician died at noon on the 16th instant, at his house in Sackville-street, from an attack of apoplexy. His researches on chloroform and other anaesthetics were appreciated by the profession.
Over generations, the gene pool of the first farmers became increasingly dominated by individuals who could drink beer on a regular basis. Most of the world’s population today is made up of descendants of those early beer drinkers, and we have largely inherited their genetic tolerance for alcohol.
There’s a reason why the world’s wealthiest people—people with near-infinite options vis-à-vis the choice of where to make their home—consistently choose to live in the densest areas on the planet. Ultimately, they live in these spaces for the same reason that the squatter classes of São Paulo do: because cities are where the action is. Cities are centers of opportunity, tolerance, wealth creation, social networking, health, population control, and creativity.
Broad Street marked the first time in history when a reasonable person might have surveyed the state of urban life and come to the conclusion that cities would someday become great conquerers of disease. Until then, it looked like a losing battle all the way.
As Lynn Margulis writes: “All the world’s bacteria essentially have access to a single gene pool and hence to the adaptive mechanisms of the entire bacterial kingdom. The speed of recombination over that of mutation is superior: it could take eukaryotic organisms a million years to adjust to a change on a worldwide scale that bacteria can accommodate in a few years.
When the next great epidemic does come, maps will be as crucial as vaccines in our fight against the disease. But again, the scale of the observation will have broadened considerably: from a neighborhood to an entire planet.
Our safety depends on being able to predict the evolutionary path that viruses and bacteria will take in the coming decades, just as safety in Snow’s day depended on the rational application of the scientific method to public-health matters. Superstition, then and now, is not just a threat to the truth. It’s also a threat to national security.
(Plagues and political unrest have a long history of following the same cycles.)
The first defining act of a modern, centralized public-health authority was to poison an entire urban population.
Whitehead was not an expert, an official, an authority. He was a local. That was his great strength.
You and I may not live to see the day,” Snow explained to the young curate, “and my name may be forgotten when it comes; but the time will arrive when great outbreaks of cholera will be things of the past; and it is the knowledge of the way in which the disease is propagated which will cause them to disappear.
They were not hacks, working surreptitiously for Victorian special-interest groups. They were not blinded by politics or personal ambition. They were blinded, instead, by an idea.
Cities were suddenly populated by a class of consumers, free to worry about other pressing matters: new technologies, new modes of commerce, politics, professional sports, celebrity gossip. That
