How do inventions take shape? How did the inventors of the sewing needle, the hammer, or the wheel find their ideas? Are these creations the result of random events, or are hidden principles at work? Using everyday objects most of us take for granted--from forks and Velcro to safety pins and doorknobs--noted cognitive psychologist Robert Weber takes a fascinating look at how our world of inventions came into being, and how the mind's problem-solving...