time paradox n.

a paradox caused by an action of a time traveller which alters history so that the action is no longer logically possible, such as travelling into the past to murder a dictator which leads to a peaceful world from which the time traveller would have had no reason to depart; cf. grandfather paradox n., temporal paradox n.

Also time-travel paradox.

SF Encyclopedia


SF Criticism

Time Travel

  • [1929 C. Cloukey Paradox in Amazing Stories Quarterly Summer 390/2 page image Charles Cloukey bibliography

    Someone, sometime later than 2806, copied Dwar Smit’s earleist calculations and directions, traveled back through time, and left them in your friend’s mail box. Dr. Hawkinson could therefore copy a machine that was not really made until centuries after his death! It sounds almost incredible at first. It’s what you might call a paradox.]

  • [1931 ‘F. J. Bridge’ Via the Time Accelerator in Amazing Stories Jan. 919/1 page image Frank J. Brueckel, Jr. bibliography

    Once more I was confronted by one of the inexplicable paradoxes of time traveling. Here this man had learned my name before I told it to him; he had learned his own future before it transpired, through history books written half a million years before his birth.]

  • [ 1941 L. S. de Camp Best-Laid Scheme in Astounding Science-Fiction Feb. 115/2 page image L. Sprague de Camp bibliography

    My dear Collingwood,…don’t drive yourself crazy trying to resolve the paradoxes of time-travel. ]

  • 1942 Fantasy Circle in Astonishing Stories June 60/2

    Another topic of discussion among stf readers which never seems to die away is that of the time-travel paradox.

  • 1942 M. Jameson Anachron, Inc. in Astounding Science Fiction Oct. 63/1 page image Malcolm Jameson bibliography

    ‘No reconciliation of the supposed time paradox is necessary,’ he droned, ‘for no paradox exists.’

  • 1949 ‘D. W. Meredith’ Next Friday Morning in Astounding Science Fiction Feb. 137/2 page image D. W. Barefoot bibliography

    As for applause, I know I’m going to be too busy finding out things about all the time-travel paradoxes that have been plaguing the theory boys.

  • 1953 D. Knight Dissecting Table in Science Fiction Adventures Dec. 121 page image Damon Knight bibliography

    Cyril Kornbluth’s Dominoes and John Wyndham’s The Chronoclasm…are beautiful jobs of writing, but their time-paradox plots strike me as stale.

  • 1979 M. J. Edwards Time in P. Nicholls Encyclopedia of Science Fiction 605/1

    The exemplary form of time-paradox story is that which takes the closed loop and complicates it.

  • 1985 G. A. Effinger Nick of Time 34 George Alec Effinger bibliography

    ‘A time-travel paradox,’ said the small man. ‘There wasn’t any failure with the equipment. It wasn’t the hardware. You just ran into one of the basic laws of the universe, something we don’t know much about yet. Fortunately it was just a little paradox.’

  • 1989 C. S. Gardner Back to Future II 67

    It creates a time paradox!… A person can’t be both alive and dead at the same time! It violates the laws of physics!

  • 1995 D. W. Smith & K. K. Rusch Star Trek Voyager: Escape xxii. 225 Dean Wesley Smith Kristine Kathryn Rusch bibliography

    And this would not set up a time paradox.

  • 2003 N. Jones & N. McIntosh Battle of the Best-ofs in Interzone (#185) 60/2 page image Neil Jones Neil McIntosh

    We particularly enjoyed ‘From Here You Can See the Sunquists’ by Richard Wadholm, which, rather than sidestepping the old time-travel paradox of meeting yourself when you back into the past, confronts it head-on and builds the whole story around the premise.

  • 2016 SFX Oct. 113/1 page image

    If there’s an equivalent to the locked-room mystery within SF, it’s surely the time-paradox story…. Only a new and novel take on the subgenre is going to hold the attention, which is where the challenge lies. Enter Peter F Hamilton, whose time-paradox, crime-thriller novella [etc.].


Research requirements

antedating 1942

Earliest cite

Astonishing Stories

Research History
Looking for both 'time paradox' and 'time travel paradox'.

Jeff Prucher submitted a cite from a Malcolm Edwards article in a reprint of the Nicholls' "Encyclopedia of SF"; Mike Christie verified the cite in a 1981 reprint, and Rick Hauptmann subsequently verified it in the 1979 first edition.
Jeff Wolfe submitted a 1989 cite from Craig Shaw Gardner's "Back to the Future Part II".
Mike Christie submitted a 1953 cite from Damon Knight's book review column in Science Fiction Adventures.
Mike Christie submitted a 1949 cite from D.W. Meredith's "Next Friday Morning".
Mike Christie submitted a 1942 cite from Malcolm Jameson's "Anachron, Inc."
Ralf Brown located and Richard Horton submitted a 1985 cite from George Alec Effinger's "The Nick of Time".
Fred Galvin submitted a 1942 cite for "time travel paradox" from an anonymous feature article, "Fantasy Circle" in the June 1942 Astonishing Stories.
Larry Doyle suggested that a 1929 time-travel story by Charles Cloukey, "Paradox" (Amazing stories Summer 1929, reprinted in Amazing, Sept. 1968) might be a likely source for a cite; Jesse Sheidlower checked the original, and while it discusses classic time paradoxes, it does not use the term itself; he added a bracketed cite.

Last modified 2022-02-28 12:07:10
In the compilation of some entries, HDSF has drawn extensively on corresponding entries in OED.