ABSTRACT
The mind's eye is a powerful tool, and is often used to gratifying effect even when a problem does not seem to be inherently visual. In this chapter, seventeen puzzles are presented in which visualization is a key to solution. The puzzles ask the reader to count ferry crossings, compute the path of a bookworm, cut a hexagon into four identical triangles, find a non-spherical solid whose coordinate projections are disks, escape from “thickland,” design a pan that burns fewer brownied, protect the Statue of David, glue pyramids together, hang a picture on two nails, tile 2-dimensional and 3-dimensional space with crosses, and hide the corners of a polyhedron from a person sitting inside it. The final theorem looks far from obvious when stated, but a picture is, literally, all that's needed for its proof.
