The first day’s discussion in my Writing and Reading Science Fiction course always began with the question, “What is science fiction?” I would solicit ideas from the class and write them on the board. The suggestions from the students would always break down into two broad categories: bottom-up, trope-based definitions, and top-down, descriptive definitions. We would talk about the implicit differences between those two approaches, then I would share and discuss historical definitions of science fiction from Damon Knight, Robert Heinlein, Darko Suvin, Ted Chiang, Ursula Le Guin, and Samuel Delany. These I would intentionally order to build towards Delany’s detailed breakdown of science fiction as a rhetorical mode. Finally, I would show the students this:


(click to enlarge)

This is based on a model initially proposed by Farah Mendlesohn in her book Rhetorics of Fantasy. The idea to order the genres as a cycle rather than linearly comes from Michael Swanwick. The inclusion of historical fiction and trope-based subgenres are my own contribution.

After drawing this diagram on the board I would explain that, as a writer, it is most useful to think of genres as different rhetorical modes, which is a different way of using the word than that employed by publishers or bookstores. Indeed, when you think of genre as being a rhetorical mode, many of the things that a publisher calls “genres” are actually subgenres, that is, trope-based definitions like many of those written on the board at the start of the conversation. For example, the YA “genre” often has its own section in a bookstore, but in fact the only distinguishing characteristic of YA fiction is the age of the protagonist. Any of these rhetorical modes can exhibit the trope of having a young protagonist, and so “young adult” appears on the diagram as a subgenre within every genre.

I also explained to the class that the boundaries between the genres aren’t firm. I would describe the variables of expectation  and explicability as like two knobs, with “real” at one end of their range and “unreal” at the other. Starting with mimetic fiction, both knobs are turned all the way to “real.” As you move around the diagram you are turning both knobs, until they are both pointing all the way to “unreal” at immersive fantasy. Then, in the step from immersive fantasy to science fiction, you turn the explicability knob back to “real.” (As Mendlesohn puts it, “The more immersive the fantasy, the closer to being science fiction.”) Finally, you start turning the expectation knob back towards “real” and move through historical fiction back to mimetic fiction.

A couple of caveats: though Mendlesohn begins with a linear relationship between the genres of fantasy in her book, she later abandons it for a model in which liminal fantasy is the origin point for all the other modes of fantasy. In that model, liminal fantasy is a central node from which the other fantasy genres branch out. So while I found value in the cyclic model as a pedagogical tool for convincing students to think about genres as rhetorical stances, it doesn’t represent the endpoint of Mendlesohn’s scholarship. Also, the diagram’s treatment of liminal fantasy, a category which Mendlesohn first defined, is rather brutally over-simplified. As I was usually teaching classes on writing science fiction, I allowed myself to hand-wave that aspect of the chart so as not to let an unfamiliar genre distract from my main point. But the one semester when I taught a class on fantasy writing I thought it appropriate to go into the concept of liminal fantasy in much greater detail.

I’m releasing this image under a creative commons license, so anyone who wishes can use it in their classroom.

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Rhetorical Map of Genres by Eugene Fischer is licensed under a Creative Commons Attribution 4.0 International License.
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