This thesis can easily be expanded out to describe speculative fiction as a whole. The writer of great science fiction does not begin the process by inventing a new law of physics; they take an existing speculation, a question, an idea - say, the possibility of faster-than-light travel - and then work backwards and build a story out of the way this speculation might affect the surrounding world - for example by revolutionising interstellar trade but changing the way humans interact forever by constantly putting their timelines at odds.