Playfair’s Commercial and Political Atlas and Statistical Breviary, much beloved by Tufte and others, is a monument in the history of communication with imagery. The simple chart here, showing the balance of trade between Norway and England as a time-series dual line plot looks totally modern and familiar to us, but was an incredible novelty in his day. Nor was he limited to linear charts: he worked with bar charts, innovative pie-charts, and combinations of several chart formats.
The text, now available in a complete facsimile edition at the link provided above, is, in addition, wonderful to read. If you enjoy reading intellectual strivers of the Enlightenment, as I do, you will enjoy this book thoroughly. He deals with sophisticated issues of data presentation and analysis in language so plain, you wonder how we got into our present mess with statistics being always associated with incomprehensible jargon. He also gets in some zingers against Adam Smith, with whom he had some differences.
Today we are inundated with statistical graphs, so it’s hard to accept that in his day, Playfair’s innovations were regarded with suspicion! The very informative introduction to this edition describes the intellectual prejudices of his day against graphical display of information. So much for a picture being worth a thousand words – in those days, they preferred the words! Pictures were thought to be unreliable, and subject to all sorts of hidden error, while words could be parsed to the bone to cut away the fatty tissue of falsity. It was Playfair’s genius to turn this on its head successfully, although he personally never made much of a go of it financially.