Part 1 of this article is here.
In classic science fiction, the story is about an idea and its results. Given X, how is human society affected? If people lived forever, how would society change? If energy were unlimited and free, what would be different? If time travel were possible, what would that mean regarding alternate realities?
Some authors would do their darnedest to keep X as close to known science as possible. Hal Clement, for example would discuss at length the physics of heavy gravity planets and stars so that X would not be “fantastic” and he could explore the notion of a race of sentient beings evolving in those conditions. Other authors cheerfully threw physics out the window and just made up a few new rules (“yep, turns out we can read people's minds after all”) so that they could get on with exploring the results of X. As readers in the genre, we agree to accept the premise of X in order to explore the ramifications within the world of the story. Read More Creating worlds – Heroic Fantasy vs Science Fiction – Part 2