According to Damon Knight, “science fiction is whatever I’m pointing at when I say ‘science fiction'”, which is about the most useless and yet most accurate definition of the genre to date. Which has not stopped countless people trying to come up with definitions of their own. They’ve even written entire encyclopaedias on the subject. These are some of the ones I have on my book-shelves…
Peter Nicholls’ 1979 The Encyclopedia of Science Fiction was the first such. I bought a paperback copy for £1 at an antiques fair back in the late 1980s, but later picked up a hardback copy for a fiver on eBay several years ago. I have two copies of the next version, Clute & Nicholl’s The Encyclopedia of Science Fiction, because I bought the hardback edition when it was published – RRP £45!; but I got it for £27 from an acquaintance who claimed to have contacts in the book distribution trade. Anyway, when I moved to the Middle East after graduation, the book went into storage. But I stumbled across a paperback copy of the US second edition in Abu Dhabi. I don’t remember where I got the James Gunn The New Encyclopedia Of Science Fiction from. The latest version of The Encyclopedia of Science Fiction is, of course, online at sf-encyclopedia.com.
A trio of coffee-table books on science fiction. The Kyle and the Holdstock I’ve had for a couple of decades. Science Fiction of the 20th Century by Frank M Robinson I found cheap on eBay a few years ago.
I don’t recall where I bought any of these three books. I’ve a feeling I purchased Clute’s Science Fiction: The Illustrated Encyclopedia in Dubai. Sci-Fi Now I’m fairly sure I’ve had since the late 1970s.
No collection of science fiction encyclopedias would be, er, complete without Clute & Grant’s The Encyclopedia of Fantasy. Lexicon der Science Fiction Literatur I bought while studying in Aachen in 1990. According to my records, I bought The Dictionary of Science Fiction Places for £2 in a discount book shop in Harrogate in 2004.
Edit: for reference, my post on critical works on science fiction is here.