The Pioneering Data Visualizations of William Playfair, Who Invented the Line, Bar, and Pie Charts (Circa 1786)

“If you see a pie chart pro­ject­ed twelve feet high in front of you, you know you’re in the hands of an idiot.” These words have stuck with me since I heard them spo­ken by Edward Tufte, one of the most respect­ed liv­ing author­i­ties on data visu­al­iza­tion. The lat­ter-day sins of pie-chart-mak­ers (espe­cial­ly those who make them in Pow­er­Point) are many and var­ied, but the orig­i­nal sin of the pie chart itself is that of fun­da­men­tal­ly mis­rep­re­sent­ing one-dimen­sion­al infor­ma­tion — a com­pa­ny bud­get, a city’s pop­u­la­tion demo­graph­ics — in two-dimen­sion­al form.

Yet the pie chart was cre­at­ed by a mas­ter, indeed the first mas­ter, of infor­ma­tion design, the late-eigh­teenth- and ear­ly-nine­teenth-cen­tu­ry Scot­tish econ­o­mist William Play­fair. Tufte includes Play­fair’s first pie chart, an illus­tra­tion of the land hold­ings of var­i­ous nations and empires cir­ca 1800, in his book The Visu­al Dis­play of Quan­ti­ta­tive Infor­ma­tion.

“The cir­cle rep­re­sents the area of each coun­try,” Tufte explains. “The line on the left, the pop­u­la­tion in mil­lions read on the ver­ti­cal scales; the line on the right, the rev­enue (tax­es) col­lect­ed in mil­lions of pounds ster­ling read also on the ver­ti­cal scale.” The dot­ted lines between them show, in Play­fair’s words, whether “the coun­try is bur­dened with heavy tax­es or oth­er­wise” in pro­por­tion to its pop­u­la­tion.

Play­fair was exper­i­ment­ing with data visu­al­iza­tion long before his inven­tion of the pie chart. He also came up with the more truth­ful bar chart, his­to­ry’s first exam­ple of which appeared in his Com­mer­cial and Polit­i­cal Atlas of 1786. That same book also con­tains the strik­ing graph above, of Eng­land’s “exports and imports to and from Den­mark and Nor­way from 1700 to 1780,” whose lines cre­ate fields that make the bal­ance of trade leg­i­ble at a glance. A much lat­er exam­ple of the line graph, anoth­er form Play­fair is cred­it­ed with invent­ing, appears just below, “exhibit­ing the rev­enues, expen­di­ture, debt, price of stocks and bread from 1770 to 1824,” a peri­od span­ning the Amer­i­can and French Rev­o­lu­tions as well as the Napoleon­ic Wars.

It’s safe to say that Play­fair lived in inter­est­ing times, and even with­in that con­text lived an unusu­al­ly inter­est­ing life. Dur­ing Great Britain’s wars with France, he served his coun­try as a secret agent, even com­ing up with a plan to coun­ter­feit assig­nats, a French cur­ren­cy at the time, in order to desta­bi­lize the ene­my’s econ­o­my. “Their assig­nats are their mon­ey,” he wrote in 1793, “and it is bet­ter to destroy this paper found­ed upon an iniq­ui­tous extor­tion and a vil­lain­ous decep­tion than to shed the blood of men.” Two years after the plan went into effect, the assig­nat was worth­less and France’s ship of state had more or less run aground. Play­fair’s mea­sures may seem extreme, but then, you don’t win a war with pie charts.

Relat­ed con­tent:

The Five Graphs That Changed the World: See Ground­break­ing Data Visu­al­iza­tions by Flo­rence Nightin­gale, W. E. B. DuBois & Beyond

The Art of Data Visu­al­iza­tion: How to Tell Com­plex Sto­ries Through Smart Design

Flo­rence Nightin­gale Saved Lives by Cre­at­ing Rev­o­lu­tion­ary Visu­al­iza­tions of Sta­tis­tics (1855)

Kurt Von­negut Dia­grams the Shape of All Sto­ries: From Kafka’s “Meta­mor­pho­sis” to “Cin­derel­la”

The 1855 Map That Rev­o­lu­tion­ized Dis­ease Pre­ven­tion & Data Visu­al­iza­tion: Dis­cov­er John Snow’s Broad Street Pump Map

W. E. B. Du Bois Cre­ates Rev­o­lu­tion­ary, Artis­tic Data Visu­al­iza­tions Show­ing the Eco­nom­ic Plight of African-Amer­i­cans (1900)

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities, the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les and the video series The City in Cin­e­ma. Fol­low him on Twit­ter at @colinmarshall or on Face­book.