Dudley attempts to impose a pattern on the entire history of human civilization. He shows how the major transformations in the character of social life have been determined by eight significant innovations: four new ways of dealing with information - writing, printing, mass media and integrated circuits; and four new ways of organizing the applications of violence - metal weapons, artillery, steam transport and heavy cavalry. Military and informational technologies are so crucial because they are instrumental in holding states together, while innovation in itself tends to produce new economies of scale.