Whenever we create a new version of the Classics of Science Fiction some titles get added and others dropped. My main reason for producing the list is to track how books are discovered and forgotten over time. Most books pass from public memory soon after they are printed, so to get on a best-of-the-best list and stay on it for years means a huge number of readers are recalling those titles decade after decade. Just study the List of Lists to see the 65 ways these books were remembered from 1949 – 2016. (Read the Introduction for our overall methodology.)

When books fall of the list, it doesn’t mean those books are no longer worthy of reading, but those titles have slipped from the minds of older readers and newer readers have never encountered them. Sometimes books are rediscovered, especially if they get new editions, produced as audio books, or made into films or television shows. Generally, books slide into obscurity. Old readers die off and younger readers never know what they missed.

Many of the titles that dropped off version 4 of the Classics of Science Fiction were books published before 1950. For version 3, we used several lists for library collection development, or critical histories of science fiction. For version 4, we had more fan polls. Version 3 had many short stories collections and anthologies that didn’t make it to version 4. Plus, many classic titles from 1950-1975 fell off. I assume newer readers aren’t discovering those books.

I feel version 4 is a better list than version 3. Most of the second half of version 3 didn’t make it to version 4. Which makes me wonder if the bottom half of version 4 will disappear when we create version 5 in ten years.

Here are the titles that fell of the list this time. The ones in red are books I’ve reread in the recent years and personally believe should be on version 4. There are plenty of books on the list below I still plan to reread. And there are stories below I have reread recently that don’t belong on the list. I won’t say which.

• 334 (1972) by Thomas Disch
• The Absolute at Large (1927) by Karel Čapek
• Across the Zodiac (1880) by Percy Greg
• Again, Dangerous Visions (1972) edited by Harlan Ellison
• Animal Farm (1945) by George Orwell
• Astounding Science Fiction Anthology (1952) edited by John W. Campbell
• Back to Methuselah (1921) by George Bernard Shaw
• The Battle of Dorking (1871) by Sir George Chesney
• Before the Golden Age (1974) edited by Isaac Asimov
• Behold the Man (1969) by Michael Moorcock
• The Best of C. L. Moore (1975) by C. L. Moore
• The Best of C. M. Kornbluth by C. M. Kornbluth
• The Best of Henry Kuttner (1975) by Henry Kuttner
• The Best of Science Fiction (1946) edited by Groff Conklin
• Beyond Apollo (1972) by Barry N. Malzberg
• The Big Time (1961) by Fritz Leiber
• The Black Cloud (1957) by Fred Hoyle
• Brain Wave (1954) by Poul Anderson
• Bring the Jubilee (1953) by Ward Moore
• Bug Jack Barron (1969) by Norman Spinrad
• Casey Agonistes (1973) by Richard McKenna
• Chronopolis and Other Stories (1971) by J. G. Ballard
• The Chrysalids (1955) by John Wyndham
• The Clockwork Man (1923) by E. V. Odle
• The Coming Race (1871) by Edward Bulwer Lytton
• Dark Universe (1961) by Daniel F. Galouye
• Davy (1964) by Edgar Pangborn
• The Death of Grass (1956) by John Christopher
• Deathbird Stories (1975) by Harlan Ellison
• Deathworld (1960) by Harry Harrison
• Deluge (1927) by S. Fowler Wright
• The Doors of His Face, The Lamps of His Mouth and Other Stories (1971) by Roger Zelazny
• Dorsai (1976) by Gordon Dickson
• Downward to the Earth (1970) by Robert Silverberg
• The Dream Master (1966) by Roger Zelazny
• The Dying Earth (1950) by Jack Vance
• E Pluribus Unicorn (1953) by Theodore Sturgeon
• The Embedding (1973) by Ian Watson
• Engine Summer (1979) by John Crowley
• Erewhon (1872) by Samuel Butler
• Final Blackout (1948) L. Ron Hubbard
• The Girl in the Golden Atom (1922) by Ray Cummings
• Gray Lensman (1951) by E. E. “Doc” Smith
• Greybeard (1964) by Brian Aldiss
• Gulliver’s Travels (1726) by Jonathan Swift
• The Hampdenshire Wonder (1911) by J. D. Beresford
• Herland (1915) by Charlotte Perkins Gilman
• The Iron Dream (1972) by Norman Spinrad
• Islands in the Net (1988) by Bruce Sterling
• The Lensman Series (1948) by E. E. “Doc” Smith
• The Listeners (1972) by James Gunn
• The Long Tomorrow (1955) by Leigh Brackett
• Looking Backward (1880) by Edward Bellamy
• The Lost World (1912) by Arthur Conan Doyle
• The Lovers (1961) by Philip José Farmer
• The Machine Stops and Other Stories (1909) by E. M. Forster
• Make Room! Make Room! (1966) by Harry Harrison
• Man Plus (1976) by Frederik Pohl
• A Martian Odyssey and Other Science Fiction Tales (1975) by Stanley G. Weinbaum
• The Midwich Cuckoos (1957) by John Wyndham
• A Mirror for Observers (1954) by Edgar Pangborn
• Norstrillia (1975) by Cordwainer Smith
• Nova (1968) by Samuel R. Delany
• Of All Possible Worlds (1955) by William Tenn
• On the Beach (1957) by Nevil Shute
• On the Wings of Song (1979) by Thomas Disch
• The Past Through Tomorrow (1967) by Robert A. Heinlein
• Perelandra (1943) by C. S. Lewis
• The Persistence of Vision (1978) by John Varley
• Play Piano (1952) by Kurt Vonnegut
• The Poison Belt (1913) by Arthur Conan Doyle
• Riddley Walker (1980) by Russell Hoban
• The Science Fiction Hall of Fame Volume One (1970) edited by Robert Silverberg
• The Science Fiction of Edgar Allan Poe (1976) by Edgar Allan Poe
• The Science Fiction of Jack London (1975) by Jack London
• She (1886) by H. Rider Haggard
• The Sheep Look Up (1972) by John Brunner
• The Short Stories of H. G. Wells (1927) by H. G. Wells
• Sirius (1944) by Olaf Stapledon
• The Skylark of Space (1946) by E. E. “Doc” Smith
• Strange Case of Dr. Jekyll and Mr. Hyde (1886) by Robert Lewis Stevenson
• That Hideous Strength (1945) by C. S. Lewis
• To-Morrow’s Yesterday (1932) by John Gloag
• Under Pressure (1956) by Frank Herbert
• Untouched by Human Hands (1954) by Robert Sheckley
• A Voyage to Arcturus (1920) by David Lindsay
• The Wanderer (1964) by Fritz Leiber
• War of the Newts (1936) by Karel Čapek
• The Weigher of Souls (1931) by Andrew Maurois
• Who Goes There? (1948) by John W. Campbell
• The Wind’s Twelve Quarters (1975) by Ursula K. Le Guin
• The Witches of Karres (1966) by James H. Schmitz
• Woman on the Edge of Time (1976) Marge Piercy
• The World Below (1930) by S. Fowler Wright

— James Wallace Harris – slightly revised from Worlds Without End.