Edward Tufte: Envisioning Information, Chapter 5: Color and Information Commentary

Coloring books are a constant reminder to children of the importance contour lines to delineate color regions, which is an important rule that Edward Tufte references at the end of the text. It creates a distinctive mark to the visualizer what sections of a piece are of a different space, or represent a different idea altogether. This feature, and an attachment to a childlike object, shows just how much of space characteristics that have been ingrained into our culture, that we as a people just naturally accept and interpret.