These are not books you read in the normal way. They don’t offer lists of rules for visually displaying evidence. Instead, these books beautifully reproduce and evaluate examples of graphs, tables, charts, diagrams, maps, “sparklines” (You’ll have to go find out what that means!), and more. They show examples from centuries of people–such as Galileo, Leonardo da Vinci, Henri Matisse, Richard Feynman, etc– trying to communicate their ideas clearly and beautifully.
Tufte also argues that producing visual representations of our ideas makes those ideas clearer to us, too. In other words–just as writing is thinking–sketching and drafting and moving visual elements around on the page are analytical tools. I can vouch for this myself. I went to Tufte’s day-long seminar last Friday, and I’ve been able to reconceive and clarify for myself the ideas in an article I finished writing two years ago but about which I am just now creating a poster. I thought I was pretty familiar with the ideas in my own completed article, and yet the sketches (and even watercolors!) have made me see the ideas more clearly and in ways that will make them much easier to talk about.
(The image shows Galileo’s sketch of the changing positions of Jupiter’s moons from one night to the next.)