Diagrams: Maps as Things to Think With
Who says this map is upside down!? Putting North at the top is an arbitrary convention that reinforces a Eurocentric value hierarchy. Twenty-one year old Australian Stuart McArthur created this map in 1979.
A diagram—a graphic representation of a thing, a system, or a phenomenon—is a wonderful thing to think with. These graphic representations take a wide variety of forms, and occur across the disciplines. They help to capture existing knowledge, provoke questions that may lead to new knowledge, and support and structure the learning of students.
To illustrate how a graphic representation can perform all these functions, let’s start with an everyday example: the map. Most commonly, a map is a two dimensional depiction of a geographic area, constituting a sort of model of a particular terrain.
Road maps are the most familiar type in everyday use. They help travelers find their way from a point of origin to a destination. The canonical paper road map emphasizes streets, intersections, highways, interchanges, political boundaries and names (cities, states), and may include major landmarks. These maps capture and communicate a wealth of existing knowledge that help motorists to find their way, whether they are seeking the fastest and most efficient route or a leisurely trip on back roads. Users do not need to be familiar with a particular region in order to use these maps successfully, making basic knowledge about the layout of a geographic area accessible to a broad public.
Maps can also stimulate questions leading to new knowledge. For the tourist, a map may invite questions about a new city, a state park or wilderness area, or a region laced with particularly curvy roads. The truck driver may wonder about the frequency of rest stops, the speed limit, the number of hills, and the availability of trucker turnouts for rest and safety. Even locals, who grew up experiencing their region through the windshield or on foot, may discover a connection between known locations, or new routes to familiar places, by looking at their home terrain with a bird’s-eye view. Specialty maps used by geologists, urban planners, watershed managers, oceanographers, and a vast number of other professional can also provoke questions and invite investigation by those trained to read these maps intended for experts.
Finally, maps support and structure learning. Novices learn to associate features of a map with features of a territory. Typical road maps highlight such conventions as putting the compass point North at the top of the map, emphasizing roads while ignoring elevation, highlighting cities and towns but not watershed boundaries or the presence of trees, portraying distance but not climate, and so forth. Road maps tell the user what is worthy of attention and what is not. They support the motorist but not the hiker, thereby reinforcing twentieth-century “car culture” and an urban or suburban bias.
Maps are a wonderful teaching tool. Because they come in many forms, teachers can ask students to compare, for example, a road map with a topographic map. With this simple exercise students can learn that maps are not perfect depictions of territories. They are created with assumptions about who will be using them and what the users will be interested in knowing. No map is “accurate” or “perfect.” In fact, maps derive their usefulness from their incompleteness, the fact that they leave out some things while highlighting others. Imagine trying to drive from Atlanta to Seattle on back roads using satellite photos: you would have to discern where roads were even when they were covered by trees or camouflaged by terrain. You might not be able to distinguish an intersection from an overpass. You would labor to pick out the features salient to your trip from the unimportant details. It’s the useful omissions and distortions in maps that give them value. The map is not the territory…and it’s shouldn’t be.
In his classic book, How to Lie with Maps, Mark Monmonier begins, “Not only is it easy to lie with maps, it’s essential…To avoid hiding critical information in a fog of detail, the map must offer a selective, incomplete view of reality.” The “little white lies” that make maps useful, however, can also be exploited by the biased and the unscrupulous, and it is important for students to learn to distinguish between the relatively benign and the insidious. What does the map highlight? What does it obscure? Whose interests might it serve to portray an area in this way? Who gets the spotlight and who or what is left in the shadows? A map of the world with Europe at the top perpetuates prejudice toward the “global south.” The racist mid-twentieth-century practice of “redlining” drew a line (sometimes literally) around minority neighborhoods, designating them as a risky place for mortgage lending and thereby depriving borrowers, regardless of their income, access to federally guaranteed home loans. Maps that show which sites have significant levels of pollution would alert residents to the dangers they faced, but such maps are not readily available to communities. If the most common maps displayed risks (drought, flooding, pollution, heat islands, and more) instead of just roads, and students learned to read and understand these, how might civic life be different?
Maps are rich ground for exploration, helping students learn dimensional thinking, critical thinking, social and cultural awareness, and navigation skills. When students learn how to “read” an artifact, they can apply these skills to many other situations and artifacts.