What is Speculative Fiction?

Sophie Playle

Often described as the ‘What if …?’ genre, speculative fiction (spec-fic) describes any work where the writer explores unproven theories in a fictional scenario. But it’s not quite as simple as that.

As a definition, this one is so loose that it can be stretched to include all fiction, in a way. At the very least, this definition fails to capture the particular flavour of this genre. So to understand the essence of speculative fiction, we need to look at the nature of the speculation being made.

Speculative fiction is distinguished by being based on unusual ideas and elevated imagination.

Let’s look at an example. In literary fiction, a character might be a missionary in an exotic location, but in speculative fiction he’d be a missionary on another planet with an attentive congregation of non-humanoid aliens (and so Joseph Conrad’s Heart of Darkness becomes Michel Faber’s The Book of Strange New Things).

What I love about speculative fiction is the very thing that makes a watertight definition impossible. Not only is it a genre in itself, but it forms a sort of umbrella over many other genres.

Wherever your writing sits, turn the dial marked ‘Big Ideas’ up to eleven and you’ve got speculative fiction. Make the idea behind your story more mundane and you’re moving away from speculative fiction territory.

Having arrived at a working definition, let’s look at some of the domains in which speculative fiction authors tend to speculate. Don’t imagine that this will be an exhaustive tour, because each domain can be further broken down into many sub-genres, which I’ll only touch upon here.


Fantasy is special because it’s the purest form of speculative fiction you can get; by definition any work of fantasy is highly speculative. Heck, most true fantasy stories are so speculative that they aren’t even set in our world. Think Philip Pullman’s His Dark Materials series, Runemarks by Joanne Harris and Terry Pratchett’s Discworld series to name but a few.

Science Fiction

Science fiction and speculative fiction are sometimes seen as synonymous – after all, authors of science fiction are speculating about plausible scientific developments (and this is what sets the genre apart from fantasy). However, science fiction and speculative fiction aren’t really interchangeable terms. I’d argue that while The Martian by Andy Weir is definitely a work of science fiction, it isn’t one of speculative fiction because at heart it’s a straightforward survival story.


When you write horror, you’re automatically moving into the ethereal and strange, which brings you closer to speculative fiction. Although many horror books are highly speculative (like Clive Barker’s outrageous novella The Hellbound Heart), you’ll also find a lot that are distinctly of this world. Body horror may be nasty, but it’s ultimately quite mundane.


Though making up a smaller section of the speculative fiction genre, historical fiction is fertile territory for the speculative fiction writer because of the almost limitless potential for rewriting events. This can be done on a fairly realistic level, as in Philip K Dick’s The Man in the High Castle, which depicts an alternative reality where Japan and Germany won World War II. Or there are even more fantastical scenarios to be had, like the classic Merlin trilogy by Mary Stewart, a re-telling of the King Arthur legend from the point of view of the aged, half-demented wizard.

A word about sub-genres

There’s a potentially limitless number of sub-genres within speculative fiction, which makes this a topic highly deserving of its own article. I’ve touched on some of them already: The Man in the High Castle is an example of alternate history, and The Book of Strange New Things is an apocalyptic tale. Sometimes, as in science fantasy, primary speculative fiction genres intersect.

Is it really important to classify my writing?

This is a question asked by many authors throughout the history of fiction, and my answer has to be a qualified yes. The nature of book marketing being what it is, you’re going to find it much easier to promote your work if you have a clear idea of which genre (and preferably sub-genre) it occupies.

Some writers like to get to know their target genre inside out before they even start writing, but it’s okay if this approach isn’t for you. You always have the option to write the thing first, then find a good editor to help you decide where your book belongs.

Sophie Playleis a professional fiction editor. She specialises in developmental editing, critiquing and copy-editing, and loves working with authors and publishers who are passionate about high-quality storytelling. Speculative fiction, fantasy, science fiction and literary fiction are her genres of choice. She's an Advanced Professional Member of the Chartered Institute of Editing and Proofreading and has a Creative Writing MA from Royal Holloway, University of London. Find out more: liminalpages.com

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