There is great value in being able to provide a brief insightful summary of an elaborate experiment, a complicated theory or a multi-faceted discussion. Suppose one of us gets on an elevator and the only other passenger is a four-star general. She smiles and asks “How is your research going?” This is one of those rare opportunities when a scientist can actually influence policy, resource allocation and the direction of science by being able to communicate effectively. Almost invariably the opportunity is lost because scientists and generals rarely speak the same language. However, there is a trick that one can employ to anticipate this rare event and that is to have something worked out in advance so as not to waste the opportunity. This is the “elevator description” of the most significant research that has been done. In another age it might have been called the “Reader's Digest” version.

That is the position the authors find themselves in now. We believe that we ought to provide a brief but insightful summary of the book you have just completed in a way that conveys the maximum amount of information, but without the mathematics that was necessary to make that information understandable when it was first presented. To accomplish this goal we review the high points of each of the chapters and then attempt to tie them all together into a coherent picture.

In the first chapter we argued that normal statistics do not describe complex webs. Phenomena described by normal statistics can be discussed in terms of averages. The fact that human populations are well represented by normal distributions of heights strongly influences the manufacturing of everything from the size of shoes, shirts and slacks to cars, computers and couches. The relative numbers of shirts in the small, medium and large sizes are determined by our knowledge of the average build of individuals in the population. The distribution of sizes in the manufactured shirts must match the population of buyers or the shirt factory will soon be out of business. Thus, the industrial revolution was poised to embrace the world according to Gauss and the mechanistic society of the last two centuries flourished. But as the connectivity of the various webs within society became more complex the normal distribution receded further and further into the background until it was completely gone from the data, if not from our attempted understanding.