Time is like quantum physics. Its observable reality is contradicted by scientific theory. We notice it pass moment by moment; we recognize that the present emerges from an unending succession of previous moments; we understand that more moments stretch ahead into the fog of the yet to come; and we talk to each other as if we shared a common experience. And yet scientists tell us that our perception of time is subjective and dependent upon what we’re doing at the moment and even how fast we are accelerating—that time does not exist as an independent reality and that the arrow of time can go backward as readily as forward. And yet we persist in trying to grasp it, to capture it in our memories, and calculate its future in our present decisions as if it were real instead of a consensual illusion.
Science fiction has seized the issue of time as one of its basic topics, in the same category as space travel, reality, and the future itself. All are useful as ways of exploring what it means to be human in a changing world. In the instance of time, realizations of the past as something tangible serve multiple purposes: to consider why the past happened the way it did, how the present emerged from it, whether it could (or should) have happened differently, whether the past could be changed either by design or by accident and how that would affect the present, whether there is a single past or alternative timelines created by critical events happening in different ways, and whether the human desire can succeed in correcting the past, a desire evident in human propensity to change its stories or even its memories to make them more admirable or more sympathetic. Explorations of the future, on the other hand, are attempts to guide or judge the present; if the past cannot be changed, at least the future is still dependent upon current decisions.
The first science-fiction explorations into the future and the past were stories placed there. For a good many generations, the only way imaginative literature could travel into the future or the past was through stories such as the anonymous The Reign of King George VI: 1900-1925 (1663) or Louis Sebastian Mercier’s Memoir of the Year Two Thousand Five Hundred (1771) and into the past by stories of cave men, like Stanley Waterloo’s The Story of Ab (1897). Jack London’s Before Adam (1906-1907), H. G. Wells’s “A Story of the Stone Age” (1897) and “The Grisly Folk” (1921), J-H Rosny’s The Quest for Fire (1911), down to William Golding’s The Inheritors (1955). Simply placing the story in the past or the future is still science fiction’s principal strategy for describing either; Washington Irving gave the process more plausibility with “Rip Van Winkle” (1819), about a man who falls asleep for twenty years and awakens to a changed world. That method of time travel was followed by a succession of authors, including Edward Bellamy with Looking Backward from the Year 2000 (1888), and even by H. G. Wells in his The Sleeper Awakes (1910), a revision of his earlier When the Sleeper Wakes. Reaching the future through a long sleep fell out of fashion until it was resurrected by the invention of cryogenics and the possibility of reviving frozen bodies or heads that came to be called “corpsicles.” Wells, though, offered a better option to sleeping-into-the-future and became famous with his first novel, The Time Machine (1895), which offered the first technological means for traveling through time, and made it seem believable with a description of the apparatus and the theory behind it (time as a fourth dimension), and used it as a means of criticizing current trends toward class division. Since then the notion of travel through time has been dominated by Wellsian machines but more often into the past, where Wells’s time traveler never ventured.
The chance translation into the past, with its possible interpretation as a dream, was an early strategy. Mark Twain used it in A Connecticut Yankee in King Arthur’s Court (1889), in which his pragmatic engineer gets a blow to the head and finds himself in King Arthur’s time where he attempts to reform the system by the introduction of modern technology. L. Sprague de Camp echoed Twain in his Lest Darkness Fall (1939): his hero gets struck by lightning and finds himself back in fifth-century Rome where he tries to save Italy from the Dark Ages. It was a tradition that Isaac Asimov would follow, though into a future empire, with his Foundation Trilogy (1942-1950) and Hari Seldon’s efforts to shorten a galactic Dark Ages with the help of “psychohistory,” a way to predict broad strokes of history through the use of the mathematics of probability. Later writers would transport their characters to earlier times through psychological methods such as hypnosis in Jack Finney’s Time and Again (1970). But time machines still dominated the field as purposeful voyages into the past with all its consequences and concerns, like Ray Bradbury’s “The Sound of Thunder” (1952) in which a tourist into the primordial past steps off a prescribed pathway, crushes a butterfly, and returns to a changed world (the “butterfly effect”). The use of machines to change the present by altering critical past events produced stories that ranged from the personal, like killing one’s own grandfather (the grandfather paradox), to world alterations, like assassinating Hitler or preventing his coming to power in various ingenious ways.
These kinds of treatments led to an entire category of stories that dealt with efforts to create or prevent alterations in history that would create presents or futures more desirable to individuals or groups. One of the earliest of these was A. E. van Vogt’s 1942 Astounding novella “Recruiting Station,” which was combined with two other stories in the 1950 Masters of Time, perhaps the first of the ChangeWar concept that imagines groups competing for control of the future by changing the past. It would be picked up by Poul Anderson in “Time Patrol” (1955) and continued for forty years in a series of stories and collections. Fritz Leiber would contribute to the ChangeWar theme with his “The Big Time” (1958).
All these stories assume the existence of alterable “timelines,” that alternative possible outcomes can be chosen by a judicious tinkering with an accessible past. That led to a category of stories in which events have happened differently without human intervention. Such alternate-history narratives became popular in the 1930s; a number of them were anthologized in J. C Squires’s If It Had Happened Otherwise (1931), which included a story by Winston Churchill, “If Lee Had Not Won the Battle of Gettysburg.” James Thurber satirized the trend in his New Yorker story “If Grant Had Been Drinking at Appomattox.” The category got new energy in 1950 with Ward Moore’s Bring the Jubilee, which imagined a world in which the South had won the Civil War; it retained the concept of the time machine by having a person in that dismal world in which slavery still existed by having its main character travel to the past and accidentally change the outcome of the Battle of Gettysburg before his return to his newly changed world of today’s reality. Philip K. Dick contributed to the rise of the alternate history with his The Man in the High Castle (1962), which assumed certain critical events that had happened differently resulted in the Axis powers winning World War II and the United States being divided between German and Japanese rule, a narrative complicated by the existence of a novel that described an alternate reality much like our own. Innumerable alternate histories have been published since, often focused on the outcomes of major wars, and finally became a category in its own right led by historian Harry Turtledove and even adopted by academic historians under the name of “counterfactuals.”
In addition to its speculative value about the way history turned out, the alternate history also raises questions about the fragility of the present, hinged as it is on events that could have turned out differently and thus the reader’s confidence in the solidity of his own reality. The more believable the author’s portrayal of the altered world, as in Bring the Jubilee and particularly The Man in the High Castle, the more accidental the world around us seems, not unlike our personal experience of the chance events or decisions that have shaped our lives.
Concerns about changing the past have motivated a number of television series such as “The Time Tunnel” (1966-1967), “Quantum Leap” (1989-1993), down to “Timeless,” as well as many films.
Another way in which concern with the past has evidenced itself in science fiction is through the possibility of observing it: what if we could see events as they actually happened rather than as they have been reported. T. L Sherred did a masterful job of considering the impact of that in his “E for Effort” (1947), in which a couple of inventors produce a camera that records the past and use it to explore the grim reality of past happenings before they get rich with films based on real history, including epics in which great battles can be included cheaply, and governments realize that the device can also film vital secrets and destroy civilization. Isaac Asimov’s “The Dead Past” (1946) raised another issue when the inventor finds that his grieving wife (and potentially a vast number of others) was using the device to obsess over her dead child; and the inventor decides to destroy it.
Einstein’s General Theory of Relativity offered new possibilities for stories about time with its consideration of the difference in its passage for people accelerating at different rates. L. Ron Hubbard (the later creator of Dianetics and Scientology) treated time dilation in his novel To the Stars (1958) in which interstellar space travelers, for whom time passes much slower than for those they leave behind, return to find the people they knew dead and their world changed. That concept also played a role in Joe Haldeman’s The Forever War (1974), and in Robert Heinlein’s juvenile novel Time for the Stars (1956) in which twins are separated and age differently (“the twins paradox”).
Frederik Pohl would treat a different aspect of Einsteinian physics in Gateway (1977), in which a character tries to cure his guilt feelings from leaving his lover in the event horizon of a black hole in which time passes so slowly that she is still dying after many years. Poul Anderson treated that concept earlier in “Kyrie” (1968) through the telepathic connection of a nun with an energy creature that sacrifices itself to save an expedition but falls into a black hole, and the woman must share its dying agonies for her entire life. I considered a somewhat different aspect in the central portion of my novel Gift from the Stars, in which travelers find themselves in a white hole where time does not exist and cause and effect are meaningless.
Finally, science fiction has explored the possibilities of the future influencing our present through the use of future technologies, a concept that gains more credibility by the likelihood that future scientists will be more advanced than those of today. Sometimes that works out in comic ways, such as the accidental transference of future devices into our time. William Tenn (Phil Klass) in “Child’s Play” (1947) imagined a “Bild-a-Man” kit falling into the life of a man whose use of it results in his own dismantling, and Henry Kuttner imagined a deadly monitoring device that looks like a television set in “The Twonky” (1942). Cyril Kornbluth had a more serious take on the possibility of an object from the future arriving in the present by accident in “The Little Black Bag” (1950) when a physician’s automated medical kit falls into the hands of a shady doctor who is finally doomed by his misuse of its miracles. Two of the most moving treatments of this concept came from Henry Kuttner and C. L. Moore in “Vintage Season” (1946) and “Mimsey Were the Borogoves” (1943). In “Vintage Season” an unusual group of people gathers in a small hotel and only at the end does the doomed contemporary character discover that they are visitors from the future who arrive just before catastrophic events when the world undergoes a “vintage season.” In “Mimsy Were the Borogoves,” a scientist in the far future tests a time-travel device by sending into our present several of his child’s toys. They fall into the home of a family with two children, a boy and a girl, who use the toys to train their minds to translate themselves into a different plane of existence (just as a previous experiment fell into the hands of Alice Liddell for whom Lewis Carroll wrote Alice in Wonderland—from which the story derived its title).
Perhaps the most influential novel about time since Wells published The Time Machine arrived in 1980 when astrophysicist and science-fiction author Gregory Benford produced Timescape, bringing his knowledge of theoretical physics to the service of imagining a means of transmitting messages to the past. The motivation was survival: an algae bloom in 1997 threatened the lives of everything on Earth, and scientists at Cambridge University were working on a project to alert scientists in the 1960s to the problem so that they could prevent the conditions that allowed the algae to become a worldwide problem. The answer was tachyons—theoretical particles that scientists speculate can only travel faster than light—which would allow the scientists to aim a message at a position in space where Earth would have been in the 1960s. But the 1997 scientists had to avoid sending complete information for fear the problem would be solved completely, their world would never exist, and therefore they could not have sent the message that saved Earth (the grandfather paradox). It was a novel of such impact that it gave its name to an entire science-fiction publishing line.
Tachyons may not exist, and if they exist we have no means of discovering them. That probably is true of time machines as well. Our best time machine for exploring the past may be memory, as faulty and as transient as it is. And our best time machine for exploring the future is science fiction and the imaginations of its authors and readers.
James Gunn, emeritus professor of English at the University of Kansas, is former president of both SFWA and SFRA, has received the top awards of both associations, and his latest novel is Transformation.