How to Lie With Maps by Mark Monmonier

Summary

  1. The purpose of this book is to promote a healthy skepticism about maps, not to foster either cynicism or deliberate dishonesty. In showing how to lie with maps, I want to make readers aware that maps, like speeches and paintings, are authored collections of information and are also subject to distortions arising from ignorance, greed, ideological blindness, or malice.

Key Takeaways

  1. Not only is it easy to lie with maps, it’s essential. To portray meaningful relationships for a complex, 3-D world on a flat sheet o paper or a screen, a map must distort reality. As a scale model, the map must use symbols that almost always are proportionally much bigger or thicker than the features they represent. To avoid hiding critical information in a fog of detail, the map must offer a selective, incomplete view of reality. There’s no escape from the cartographic paradox: to present a useful and truthful picture, an accurate map must tell white lies.
  2. Maps have 3 basic attributes: scale, projection, and symbolization. Each element is a source of distortion. As a group, they describe the essence of the map’s possibilities and limitations. No one can use maps or make maps safely and effectively without understanding map scales, map projections, and map symbols
    1. Scale – most maps are smaller than the reality they represent, and map scales tell us how much smaller. A map can state its scale in 3 ways: as a ratio, as a short sentence, or a simple graph. You should always seek out the scale
    2. Projections – Map projections, which transform the curved, 3-D surface of the planet into a flat, 2-D plane, can greatly distort map scale. Be aware of these distortions 
    3. Symbols – graphic symbols complement map scale and projection by making visible the features, places, and other locational information represented on the map. By describing and differentiating features and places, map symbols serve as a graphic code for storing and retrieving data in a 2-D geographic framework. 
  3. Be wary of not only the known cartographic manipulator but also the careless map author unaware of the effects of aggregation and classification. Also question the definitions, measurements, shortcuts, and motives of a government agency, research institute, or polling firm that generously provides its data – even the most conscientious mapping effort is undermined by flawed data
  4. Recognizing the map’s versatility and its potential to play dual roles should enhance the informed map viewer’s healthy skepticism about a map author’s expertise or motives. But neither this recognition nor the map’s demonstrated ability  to distort and mislead should detract from an appreciation of the map’s power to explore and explain geographic facts. White lies are an essential element of cartographic language, an abstraction that is enormously useful for analysis and communication. Like verbal language and mathematics, though, cartographic abstraction has costs as well as benefits. If not harnessed by someone who is knowledgeable and with honest intent, the power of maps can get out of control. 

What I got out of it

  1. Enjoyed the book and the core principles are really important, but it is a book which could have been a blog post. Applies directly to the idea that “the map is not the terrain” and we can apply this idea far more broadly than just related to maps (financial statements are not a business, etc, etc)