Axelrod advocates that Edison was not so much a genius as a keen observer who was focused on innovation (incremental improvement) rather than invention. Pulling from a substantial archive of examples, he illustrates how Edison focused on "gap analysis" in product design - looking for the weakest elements of a device and work-arounds or improvements he could make on those elements. At first the format of the book (an example, followed by a maxim that the author draws from the example) seemed a little contrived - but the author's maxims do a good job of providing structure, as well as illustrating how the examples apply to current product development. I also liked the persistent theme of Edison's preference for the tactile over the abstract. The book also does a good job in putting a couple of Edison's magnificant failures in the context of a life devoted to experimentation. A short read - well worth the effort.