Since its emergence in the seventeenthcentury, science fiction has been a sustained, coherent and subversive check on the promises and pitfalls of science. In their turn, invention and discovery have forced fiction writers to confront the nature and limits of reality. Different Engines explores how this fascinating symbiosis shapes what we see, do, and dream.   From Johannes Kepler'sSomnium to Arthur C. Clarke's2001, science fiction has emerged as a mode of thinking, complementary to the scientific method. Science fiction's field of interest is the gap between the new worlds uncovered by experimentation and exploration, and the fantastic worlds of the imagination. Its proponents find drama in the tension between the familiar and the unfamiliar. Its readers, many of them scientists and politicians, find inspiration in the contrast between the ordinary and the extraordinary. Brake and Hook'sDifferent Engines is a unique, provocative and compelling account of science fiction as the arbiter of progress.