The Science Fiction and Fantasy Genres

     What does it mean to say that science fiction tries to make its speculations plausible while fantasy does not? Basically, fantasy writers don't expect you to believe that the things they're describing could actually happen, but only to pretend that they could for the duration of a story. Fantasy readers understand that and willingly play along. Science fiction writers, on the other hand, try to create worlds and futures (and aliens) that really could exist and do the things they describe. Their readers expect that of them, and write critical letters to editors and authors when they find holes in the logic (or the assumptions) that would make a science fiction story impossible.

     Often the same basic story material can be treated as either science fiction or fantasy, depending on how the writer approaches it. For example, the old fable of "The Goose That Laid the Golden Eggs" is fantasy because real geese don't lay golden eggs and the story makes no attempt to convince you they could. It merely asks you to consider what might happen if one did. Isaac Asimov's short story "Pate de Foie Gras" takes this basic idea and turns it into science fiction by postulating a biochemical mechanism so that readers can judge for themselves whether it might actually work.

     Fantasy is fun; but for some readers there's something extra special about a story that not only stretches the imagination, but just might be a real possibility.

Stanley Schmidt, Aliens and Alien Societies, 1996