Its books might feature deadly androids or cowardly wizards, but the history of the UK publishing company Gollancz reads like one of the fantastical stories with which it has become synonymous. Fifty years ago, its editor Hilary Rubenstein was so intrigued by a series of lectures given by Kingsley Amis on science fiction writing that he published them in book form as New Maps of Hell. Little did Rubenstein know what he had begun. In the five decades that followed, Gollancz has been responsible for some of the most exciting, groundbreaking and best-selling science fiction and fantasy writing.
Rubenstein quickly followed that first foray with The Drowned World - a prescient novel by a hopeful young writer detailing the effects of global warming. He was called JG Ballard, and neither Gollancz nor Ballard has looked back. This was the company that took a punt on publishing Frank Herbert's Dune in the UK - now thought to be the biggest-selling science fiction book ever. It has also published work by Arthur C Clarke, William Gibson and Terry Pratchett, and, although subsumed these days into the Orion Publishing Group, its contribution to science fiction and fantasy writing is stellar.
Gollancz marked the anniversary by asking readers to choose their favourite books from a list of 50, of which 10 are reissued this week in the classic yellow jackets that became the imprint's calling card back in the 1960s. Eric by Pratchett, Philip K Dick's Do Androids Dream of Electric Sheep?, I Am Legend by Richard Matheson and Dune have all made it - Clarke was not so lucky.
But this is a time to take stock as well as to celebrate. These are some of literature's biggest, most respected names. And yet it's still the case that science fiction and fantasy writing struggle to be taken seriously as literary forms. Even Margaret Atwood, whose post-apocalyptic novel Oryx and Crake was nominated for the Booker prize, prefers her work not to be filed under science fiction. "I call it speculative fiction," she told The National this year. "I have no real interest in writing about things with tentacles that talk."
It's a cynical thought, but perhaps Atwood was nominated because she had distanced herself from the science-fiction genre. Recognition from a literary judging panel is hardly the be-all and end-all: the likes of George RR Martin - the multimillion-selling author of the series of books adapted to huge acclaim as the television series Game of Thrones - hardly need the publicity that a Pulitzer or a Booker prize would provide. Still, it does seem odd that the Booker longlist this year once again celebrates historical novels, century-spanning epics and psychological dramas, but not the sheer invention and daring storytelling present in, say,China Mieville's Embassytown. It is a novel as competently and thrillingly written as most of the books on the list - it just happens to be set on the planet Arieka.
"Science fiction certainly has become a lot more literary in its ambitions," says Marcus Gipps, a current editor at Gollancz. "But that hasn't quite happened with fantasy yet, probably because many potential authors see Tolkien as something of a dead end as far as how the genre is represented. But what's interesting is how many established authors do 'dabble', for want of a better word, in science fiction. Look at Will Self, Margaret Atwood or Cormac McCarthy."
Science fiction is probably more enticing for a literary novelist because it deals in ideas which often have some dystopian human element - take George Orwell's Nineteen Eighty-four - whereas fantasy can often get bogged down in dreaming up another Middle Earth. But when the Booker winner AS Byatt declares Pratchett her hero, as she did at the Edinburgh International Book Festival last month, perhaps things are changing in that realm, too.
"Yes, and we publish some fantasy authors who would certainly consider themselves literary," adds Gipps. "Someone like Graham Joyce, for example, may not be writing stories with giant quests in them like Tolkien, but the books are still fantastical in scope and his reputation is well-deserved."
Joyce's settings are as diverse as a haunted Jerusalem (Requiem) and the French Alps (his latest book, The Silent Land), so nobody could accuse him of pandering to fantasy or science fiction cliché either. In fact, we may be entering a new phase of more literal writing - last week, Nasa trumpeted a new partnership with the science-fiction publisher Tor/Forge Books to produce a range of "scientifically accurate and entertaining" novels.
Gollancz, meanwhile, will continue to publish the best science fiction and fantasy it comes across, whether it's scientifically plausible or not.
"You know, I'm told people used to track down those yellow jackets in bookshops as soon as they were published," says Gipps. "And what's so encouraging is that many of these books still sell very well, decades on."
Which, in the end, is a seal of approval a literary prize can never quite bestow.
The Gollancz 50 Top Ten is now available.