This new collection of critical essays on science fiction and fantasy literature and media features the following pieces: "The Last Chocolate Bar and the Majesty of Truth: Reflections on the Concept of 'Hardness' in Science Fiction," "How Should a Science Fiction Story End?", "The Third Generation of Genre Science Fiction," "Deus ex Machina; or, How to Achieve a Perfect Science-Fictional Climax," "Biotechnology and Utopia," "Far Futures," "How Should a Science Fiction Story Begin?", and "The Discovery of Secondary Worlds: Notes on the Aesthetics and Methodology of Heterocosmic Creativity."