Design and science fiction do much the same thing. Sci-fi uses characters in stories to describe a possible future. Similarly, the design process uses personas in scenarios to describe a possible interface. They’re both fiction. Interfaces only become fact when a product ships. The main differences between the two come from the fact that design mainly proposes what it thinks is best, and sci-fi is mostly meant to entertain. But because sci-fi can envision technology farther out, largely freed from real-world constraints, design can look to it for inspiration and ideas about what can be done today. See Chapters 1 and 14.