Because science has played the leading role in defining our world today, science fiction has become the twentieth century's most characteristic form of literature. It excels at articulating the new possibilities for good and evil that shape our destinies in an age when science has created technologies once beyond even the reach of fantasy. Reflecting too the global nature of science, science fiction is the most international of all genres. Moreover, no other form better illustrates the fact that genres serve ethical as well as aesthetic purposes. With impressive scope and vitality, science fiction engages us in a moral dialogue centering on whether science will ultimately advance humanity or destroy it. Given the sweeping range of these urgent concerns, it is no surprise then that science fiction counts among its ranks an amazingly diverse lot of writers, including H.G. Wells, Aldous Huxley, George Orwell, Ursula K.