In the design of a product, there should be a balance between simplicity and generality. In one sense the best product is the one that speaks directly to the decision maker, respecting her or his particular abilities, relating to the issue he or she is dealing with. On the other hand, it is nice to have a product of such good design that it can serve the decision maker, his or her advisor, those in other areas, perhaps the public and the courts. Mapmakers, of course, are well aware of this design problem. A map’s usefulness is increased by adding a new type of information and yet decreased at the same time because the map becomes more cluttered. A map that “shows” everything shows nothing, because it is black.