This is a sustained argument about the idea of science fiction by a renowned critic. Overturning many received opinions, it is both controversial and stimulating Much of the controversy arises from Westfahl's resurrection of Hugo Gernsback - for decades a largely derided figure - as the true creator of science fiction. Following an initial demolition of earlier critics, Westfahl argues for Gernsback's importance. His argument is fully documented, showing a much greater familiarity with early American science fiction, particularly magazine fiction, than previous academic critics or historians. After his initial chapters on Gernsback, he examines the way in which the Gernsback tradition was adopted and modified by later magazine editors and early critics. This involves a re-evaluation of the importance of John W. Campbell to the history of science fiction as well as a very interesting critique of Robert Heinlein's Beyond the Horizon, one the seminal texts of American science fiction. In conclusion, Westfahl uses the theories of Gernsback and Campbell to develop a descriptive definition of science fiction and he explores the ramifications of that definition. The Mechanics of Wonder will arouse debate and force the questioning of presuppositions. No other book so closely examines the origins and development of the idea of science fiction, and it will stand among a small number of crucial texts with which every science fiction scholar or prospective science fiction scholar will have to read.