t \ '\& \ s the 2O16 elec- tion approaches, we're hearing a lot about "red states" and "blue states." That idiom has become so ingrained that \ we've almost forgotten where it ori.gi- nally came from: a data visualization. In the 2000 presidential election, \ the race between Al Gore and George \ W. Bush was so razor close that broad- casters pored over electora-l college maps-which they typically colored red and blue. What's more, they talked about those shadings. NBC's Tim Rus- sert wondered aloud how George Bush would "get those remaining 61 electoral red states, ifyou will," and that langrrage became Iodged in the popular imagina- tion. America became divided into two colors-data spun into pure metaphor. Now Americans even talk routinely HowData about "purple" states, a mental visual- ization of political information. We live in an age of data visualiza- tion. Go to any news website and you'll WontheWest graphics see charting support for the presidential candidates; open your iPhone and the Health app will gener- ate personalized graphs showing how active you've been this week, month or Early lives, year. Sites publish charts showinghow infographics saved soldiers' the climate is changing, how schools debunked myths about slavery and are segregating, how much housework mothers do versus fathers. And news- helped Americans settle the frontier papers are increasingly flnding that readers iove "dataviz": In 2013, BY CLIVE THOMPSON illustration by Kotryna Zukauskaite the New York Times'most-read July . August 2016 I sMrrHSoNrAN.coM 23 social issues with hard facts, if you ence, but Playfair seemed to intuit couldfind awayto analyze it," says Mi- some of its principles. He suspectedthe chaei Friendly, a professor ofpsychol- brain processed images more readily ogg at York Uni.versity who studies the than words: A picture really was worth history of data visualization. "The age a thousand words. "He said things that of data really began." sound almost like a 20th-century vi- story for the entire year was a visual- An early innovator was the Scot- sion researcher," Spence adds. Data, izal-io:n of regional accents across the tish inventor and economist William Playfair wrote, should "speak to the United States. It makes sense. We live Playfair. As a teenager he apprenticed eyes"-because they were "the best in an age of Big Data. If we're going to to James Watt, the Scottish inventor judge ofproportion, being able to es- understand our complex world, one who perfected the steam engine. PIay- timate it with more quickness and ac- powerful way is to graph it. fair was tasked with drawing up pat- curacy than any other of our organs." But this isn't the fi.rst time we've dis- ents, which required him to develoP A reaily good data visualization, he covered the pleasures of making infor- exceilent draft ing and picture-drawing argued, "produces form and shape to mation into pictures. Over a hundred skills. A.fter he left Watt's lab, Play{air a number of separate ideas, which are years ago, scientists and thinkers found became interested in economics and otherwise abstract and unconnected." themselves drowning in their own flood convinced that he could use his facility Soon, intellectuals across Europe ofdata-and to help understand it, they for illustrationto make data come alive. were using datavisualization to gfapple invented the very idea ofinfographics. 'An average political economist with the travails of urbanization, such wouid have certainly been able to pro- as crime and disease. In France in the The idea of visualizing data is o1d: duce a table for publication, but not 1830s, a Iawyer named Andr6-Michel After all, that's what a map is-a rep- necessarily agraph," notes Ian Spence, Guerry created maps showing "moral resentation of geographic informa- a psychologist at the University of statistics." Hewas arnongtheflrstto use tion-and we've had maps for about Toronto who's writing a biography shadings to show data-darker where 8,000 years. But it was rare to graPh of Playfair. Plafair, who understood crime was worse or illiteracyhigher, for anything other than geography. Only both data and art, was perfectly posi- example. His maps were controversial, a few examples exist: Around the 11th tioned to create this new discipline. because they rebutted conventional century, a now-anonymous scribe cre- In one famous chart, he plotted the wisdom. French social critics believed that lower education ied to crime, but the maps suggested this wasn't true. ri i-r':ii,: i ; a'l i.:.i:i. "Clearly," Guerry wrote, "the relation- ship people talk about does not exist." 3 Data-based social science was born. i.. 1.. r.ir t:.1'" .i. :: i: i:..* :-. :! :'::.. i i ii { By the middle of the 19th century, :;1..t' i':i1:i:ri-:: i +ir;'+a :: 1','1.. I "moral statistics" were booming and n scientists were using data visualiza- ! ated a chart ofhow the planets moved price of wheat in the United Kingdom tion to quash epidemics. When cholera through the sky. By the l8th century, against the cost of labor. People of- ravaged London in 1854, the physician scientists were warming to the idea ten complained about the high cost of John Snow mapped out incidences, and of arranging knowledge visually. The wheat and thought wages were driving noticed a large cluster around the wa- British poiymath Joseph Priestley the price up. Plafair's chart showed this ter pump on Broad Street. The skeptical produced a "Chart ofBiography," plot- wasn't true: Wages were rising much city council closed the pump, the epi- ting the lives ofabout 2,000 historical more slowlythanthe cost ofthe product. demic subsided, and Snow's map helped fi.gures on a timeline. A picture, he ar- "He wanted to discover," Spence nudge forward a cr-ucial idea: that dis- g-ued, conveyed the information "with notes. "He wanted to find regularities eases could be causedbycontactwith a:r more exactness,,and in much less time, or points of change." Playfair's illus- as-yet-unknown contagion-bacteria. than it [would take] by reading." trations often look amazingly modern: Still, data visualization was rare In one, he drew pie charts-his inven- ln mid-l9th-centuryAmerica, otie 1Q because data was rare. That began to tion, too-and lines that compared the oI the Drggest socral lssues *r, Y change rapidly in the early 19th cen- size of various country's populations tury, because countries began to col- against their tax revenues. Once again, lect*and publish-reams of informa- the chart produced a new, crisp analy- tion about their weather, economic sis: The British paid far higher taxes activity and population. "For the first than citizens ofother nations. time, you could deal with important Neurology was not yet a robust sci- 24 sMlrHSoNlAN.cOM I July. August 2O16 Lincoln was fascinated by this map, J6 consulting it so frequently during the ml Civil War that it showed "the marks nuf of much service," as an official por- fltr|l traitist, Francis Bicknell Carpenter, :1ffi Iater recalled. One day Carpenter had lt slavery. Arld it was slavery that propelled paratively slave-free. This suggested borrowed the map to examine it, when il some of the country's most remarkable that the west would care less about Lincoln came into the room. Trrdr data visualizations: "slave maps." fighting to preserve slavery; indeed, it "You have appropriated my map, M When Southern states began to se- might even switch sides and join the have you?" said Lincoln. "I have been @ cede in 1860 and 1861, Union forces Unionists. The map was a deeply po- looking all around for it." The president fl{ invaded Virginia to try to beat back Iitical data visualization, points out put on his spectacles, "and sitting down xm the secessionists. But where should Susan Schulten, a historian at the Uni- upon a trunk began to pore over it very f,il they concentrate their forces? In the versity of Denver and author of Map- earnestly," as Carpenter later wrote. I& midst of the flghting in June 1861, the ping the Natiorc. It was trying to show Lincoln pointed to the position where l federal government's Coast Survey that only a relative minority ofVirgin- Judson Kilpatrick's cavalry division m department produced a fascinating ians supported-and beneflted from- of the Army was now fi,ghting Con- ,!L map of Virginia that suggested a strat- slavery. It suggested military strategli, federate troops. "It is just as I thought d ery. Using data from the latest census, too: Try to pit the west against the east. it was," he said. "He is close upon qrii the map showed the concentration of "Itwas abreakthrough map," Schui- County, where slaves are thickest. Now- rmfr slaves in each county of Virginia: The ten notes. "It was an attempt to influ- we ought to get a 'heap' of them, when mi darker the county, the higher the per- ence how the government saw the he returns." Much as with the Virginia Ell centage of the population enslaved. nation, and how the military under- map, Lincoln used the map to under- One trend immediately jumped out: stood it. It drove Lincoln's attention to stand the country in a new way-to see ir eastern Virginia was the hotspot of where slavery was weakest." where Southerners would be most, and im slavery. The western region was com- Soon after, the U.S. Coast Survey least, eager to fight the North. m produced yet another map charting rd - i:;':+: ::::+ i4:1.t1;+.iei$iEl::'r:i "E =riij: rEgi:41t'iiri'i=" {x :rl:;:i-'i'ii #ir';!1.i18 ;i':r:iJ {ilfi+.li+1+: it}L:a!}.