Future Times Three (original title Le Voyageur imprudent, i.e. "The Careless Traveller"), by René Barjavel, is a seminal novel about Time Travel and a cornerstone of French Science Fiction, first published between 1943 and 1944.
In the middle of World War II, young mathematician Pierre Saint-Menoux meets wheelchair-bound scientist Noël Essaillon (as well as his beautiful daughter Annette), inventor of the substance that allows time travel — Noëlite. Thankful to Pierre, whose mathematical work allowed the Noëlite breakthrough, Essaillon enlists him in the exploration of time, using Noëlite pills at first, then a special "time suit".
Written when Time Travel Tropes were not yet codified, Future Times Three has too many ideas to explore to remain confined to a single plot point. Consequently, the novel is organized as a series of Story Arcs: the introduction and testing of time travel; the exploration of the future, especially the collapse of society in 2052 and the unrecognizable world of the year 100.000; Pierre's attempt, after Essaillon's death, to escape wartime hardship by turning time travel to more practical (though dangerous and morally dubious) applications. What gets Pierre in the end, however, is his existential curiosity: he sets out to kill Napoleon to see if history can be changed, only to kill his own great-grandfather by accident and vanishing.
Concentrating more on the philosophical and existential consequences of Time Travel rather than the technical aspects, the book explores — and sometimes invents — many Time Travel concepts, such as the extent to which history can be changed, the ethics of saving someone who was supposed to die and whether people from the past count as "real" or not since they're already dead from your point of view. The novel is often credited with inventing the Grandfather Paradox, although this particular claim is debatable.*
Future Times Three provides examples of:
- After the End: Pierre spends some time visiting the year 100,000, and gets to see how the human race evolved after the disappearance of electricity caused the society to collapse in the 21st century.
- Apocalypse How: When he visits 2052, the protagonist witnesses a planet-wide societal collapse to pre-industrial levels, due to the mysterious "disappearance" of electricity.
- Artistic License – Biology: The world of the year 100,000 contains some impossibilities, such as humans with no anus because "they use 100% of the food they eat".
- Artistic License – Physics: Electricity disappears in the year 2052 without explanation. Any electrical device used after that time simply ceases to function.
- Exty Years from Publication: The end of civilization takes place in 2052, 110 years after the novel's setting in 1942. In fact, Pierre at first wanted to visit the future in 100 years; Essaillon convinces him to make it 110 to check a Nostradamus prophecy that's supposed to take place in that year.
- Genius Cripple: Essaillon, the inventor of Time Travel, is chair-bound because he lost his feet.
- Grandfather Paradox: This happens literally when Pierre tries to assassinate Napoleon Bonaparte before his rise to power: at the last moment, a soldier jumps to take the bullet and save Bonaparte. This soldier is of course the time-traveler ancestor. The time-traveler is then wiped out from existence. There is even an appendix explaining the paradox at length (including the fact that, for the time-traveler, there is no real ending — he is constantly oscillating between existing and non-existing. The ending of the novel however makes it clear he does not exist anymore — his fiancée is celibate, and the man he helped build the time machine in the first place is fruitlessly trying to make it work).
- Hive Caste System: Humans of the year 100,000 are split into different subspecies with different mansions: sexless workers who tend to farm animals, "eaters" who are little more than a stomach and a mouth, muscular Super Soldiers with Absurdly Sharp Claws, and so on.
- In Spite of a Nail: Despite Pierre accidentally erasing his neighbour, an eccentric architect, from history, a building the architect had designed still exists in the present day, have been designed by a different architect. This causes Pierre to wonder what would happen if he tried to cause a more important change to history.
- Just One Second Out of Sync: Essaillon's time machine includes a setting where the user quickly alternates between shifting one second into the future and into the past, making them invisible and intangible but still able to perceive the world around them.
- Mental Time Travel: Essaillon's prototype, the Noëlite pills, work like this: when you take them, you will "rewind" or "fast forward" to your body as it was (or will be) a set amount of time in the past (or future).
- Our Time Machine Is Different: The novel starts with pills that allow Mental Time Travel; a substance that allows to stop time and a suit that allows for "proper" Time Travel are invented later.
- Pineal Weirdness: Treated slightly more realistically than most examples. In the far future, a subspecies of humanity that specializes in improved eyesight has three eyes on stalks. One of them is the pineal gland, which has (re)gained full functionality as a visual organ.
- Ret-Gone:
- Pierre accidentally appears at his neighbour's parents wedding during one of his travels. The shock drives the bride mad and the wedding is cancelled, and Pierre discovers when he comes back to the present that his neighbour was never born.
- This is Pierre's eventual fate after he accidentally kills his grandfather.
- Ripple-Effect-Proof Memory: Downplayed. Pierre is able to remember for some time that the past used to be different after he accidentally changes it, but the knowledge soon fades from his mind.
- Science Is Bad: One of the underlying themes of the novel, like in most of Barjavel's works. Essaillon eventually comes to conclude that preventing his own death via time travel is sacrilegious, and accepts to die, along with his maid who they had similarly saved before. The future civilisation does not rely on technology anymore (although it can be debated on whether it can be considered a utopia or a Bad Future). Finally, Pierre's misuse of the time machine causes him to erase himself from history.
- Shared Universe: The future Pierre visits in 2052 takes place some time after the events described in one of Barjavel's previous novels, Ashes, ashes. A footnote invites the reader to check it to know what happened.
- Tele-Frag: A variant not exactly due to teleportation. At some point Pierre switches off the Just One Second Out of Sync setting of the time machine, which allows him to become ghost-like, while he goes through a cloud of smoke. The smoke merges into his blood and he barely survives from severe carbon dioxide poisoning.
- Time and Relative Dimensions in Space: The time machine allows to program the destination time, but only the time traveller's thoughts can decide where they will land, so Pierre needs to focus on a specific place as he switches the time machine. This requires some training as his first attempts cause him to appear either in the privy, the pantry, or Annette's bed. Later on, this has dramatic consequences when he lets his mind wander during a time trip and he ends up disrupting his neighbour's parents' wedding, erasing the poor guy from history.
- Timey-Wimey Ball: The novel handles inconsistently how people remember alterations to the past. Pierre remembers not meeting Essaillon's maid on his first visit because she was dead at the time before they resurrected her via time travel (and the maid herself somehow seems to know that she should be dead), and the main characters remember Essaillon's death before they change it via time travel (including Essaillon himself). On the other hand, characters that are Ret-Gone due to Pierre's changes to the past are forgotten, including eventually by Pierre himself. Then there is how the characters use Mental Time Travel to go back in time before the war to buy any supply they run out of in the present, which should mean that at one point in the past their cupboards must have been bursting with supplies.
- To the Future, and Beyond: Pierre visits both the year 2052 — where he witnesses the collapse of civilization — and later the year 100,000, where what's left of mankind has evolved into something nearly unrecognizable. Some reconnaissance trips between the two ages help him understand how this evolution took place.
