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What We Now Know to Be True

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Dr. Melik: This morning for breakfast he requested something called "wheat germ, organic honey, and tiger's milk."
Dr. Aragon: Oh, yes. Those are the charmed substances that some years ago were thought to contain life-preserving properties.
Dr. Melik: You mean there was no deep fat? No steak or cream pies or... hot fudge?
Dr. Aragon: Those were thought to be unhealthy, precisely the opposite of what we now know to be true.
Dr. Melik: Incredible.

So you've got this great idea for a science fiction story. There's just one problem: an element of the story is blatantly contradicted by a piece of actual science, and you don't want it to look like you honestly didn't know this.

But wait! Science Marches On, right? Science is always evolving, and sometimes what we thought was certain turns out to be incomplete or incorrect. So in a story involving people from the future, ahead-of-their-time scientists, or Sufficiently Advanced Aliens, one way of getting around a scientific inaccuracy is to mention the current theory... and then have one of the characters dismiss it as an outdated misconception.

This serves as a quick Lampshade Hanging which acknowledges the departure from the facts, and allows you to get on with the story. This kind of dialogue can also be used when the science itself is in a state of flux at the time of writing—the characters discuss the competing theories, and whichever one "was proven accurate" is the one taken as accurate in the story, whatever happens later in Real Life.


This trope can also be Played for Laughs, especially when the difference from real-world science is ludicrous: "People in the twenty-first century used to think that? They must have been really stupid!"

Compare Outgrown Such Silly Superstitions (for cases involving cultural or relgious ideas rather than scientific ones) and Necessary Weasel (for cases where ignoring some inconvenient real-world restriction has become a standard part of a genre).



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  • In Journey to the Center of the Earth, Axel expresses concern that the adventuring party will encounter great heat and pressure in the interior of the Earth, which will probably kill them. Professor Lidenbrock argues that the heat will not be great, and they will be able to acclimate to the pressure. He's right.
    • In fact, this was a popular theory in the days of Jules Verne: that the only thing that happened as you get closer to the center of the earth is that pressure continued to increase, until you would eventually get to a point where the pressure was so great that the air itself was forced into solid form, representing the core. It was based on this theory that he wrote the story.
  • Isaac Asimov:
  • In a Discworld book, Vetinari comments how centuries ago they thought the Disc was round, but now it's a scientific fact it's a disc on the back of four elephants standing on a giant turtle.
  • The advanced aliens in the Uplift universe have nothing but contempt for the Earth concept of the continuum, and thus for any science not based on discrete mathematics. This may be justified, since even some contemporary Earthlings regard the continuum as a useful shortcut that we can forget about once we have sufficient computing power.
    • Except this is just a trap for Galactic races, laid out by founders of this society - they didn't want to be bothered by children, so they limited they scientific abilities to make them unable to reach them.
  • Atlas Shrugged: Galt's engine is called out as working on a new principle and proving several laws of physics to be false. Unkind people have suggested it harnesses the power of Plot.
  • In one of the Animorphs books, the alien Ax is looking through the other Animorphs' text books and comments, "That's not how gravity works at all."
    • Although, modern physics is still working out how gravity works on a quantum level.
  • Many, many, many science fiction stories that have some form of Faster Than Light Travel will include some reference to (Scientist) who discovered the theory which superseded Relativity, and thus allowed faster than light travel.
    • To be fair, relativity does allow for particles called "tachyons", which would have imaginary mass (that is, their mass would be an imaginary number) and would always travel above the speed of light, never being able to slow down below it. Of course, there is no way to turn normal particles into tachyons or vice versa. Scientists don't take tachyons very seriously because their simple presence would cause huge amounts of Cherenkov radiation, which has never been found to occur outside particle accelerators.
    • This very fact is riffed in, of all places, a Donald Duck comic, where Gyro Gearloose has built an FTL-capable spaceship. (Something which happens somewhat regularly.) When asked how it works, he replies that it transforms the ship's particles into tachyons for the journey... prompting Hewey to mention that he thought the existence of tachyons to be merely theoretical. "Oh, they didn't exist until I invented them." was Gearloose's reply.
  • Oddly enough, this sort of reasoning is sometimes used in actual science textbooks (usually when the writer themselves hasn't checked the facts and is just repeating the popular view). A good example is in biology where this trope is that Pasteur "disproved" the theory of spontaneous generation. Technically, he only disproved that any form of life was spontaneously generating from non-life in his time. No one can scientifically "prove" or "disprove" that it ever has happened, since the statistically infinitesimal odds of abiogenesis occurring make it strictly a one-shot event that can't be replicated to be observed and studied, much like the Big Bang.
  • Done in Call Me Joe, where Jupiter turns out to have a solid surface.
  • Matthew Joseph Harrington uses this gag a few times in the stories he wrote for the Man-Kzin Wars series: lung cancer was discovered to be caused by a virus, not smoking, and the asteroid that killed the dinosaurs hit Iceland, not the Yucatan.
  • In The Giants Trilogy, we discover that conservation of energy isn't entirely true - there are ways to produce free energy.
  • The Frank Herbert novel The Dragon in the Sea was set on a futuristic submarine where vacuum tubes were a plot element. A named but unspecified 'effect' was used to justify their not having been replace by transistors.
  • The Hitchhiker's Guide to the Galaxy: Parodied. After an explanation on the nature of Magratheea, and how it's inhabitants routinely made planets, the Guide finishes this explanation with: "Of course, in these enlightened days, no-one believes a word of it."

    Live Action TV 
  • The Tollans, an advanced human civilization in Stargate SG-1, have studied quantum physics... "among other misconceptions of elementary science".
    • In the early days of quantum mechanics, many scientists (including the likes of Einstein) were convinced that, to put it simply, there had to be a logical explanation behind the mess that is quantum. Bell's theorem proved them wrong. Kinda. 
  • Doctor Who, "Shada":
    The Doctor: What? Do you understand Einstein?
    Parsons: Yes.
    The Doctor: What? And quantum theory?
    Parsons: Yes.
    The Doctor: What? And Planck?
    Parsons: Yes.
    The Doctor: What? And Newton?
    Parsons: Yes.
    The Doctor: What? And Schoenberg?
    Parsons: Of course.
    The Doctor: You've got a lot to unlearn.
  • Blake's 7 pulls a two-for-one example in the pilot episode, when the cast discover that their newly acquired spacecraft goes really, really fast:
    Blake: You mean we crossed the antimatter interface? That's impossible.
    Avon: That's what they said about the light barrier.
  • In an episode of The Outer Limits (1995), some visitors from the future arrive and meet some present-day scientists. When the one of present-day researchers mentions time-dilation to a visitor she's chatting with, he winces a bit, although he doesn't correct her assumptions because he can't afford to change history by telling her where her ideas are wrong.

    Newspaper Comics 
  • Monty: In one storyline, Monty spends the night in an old mansion and asks time-travelling Doc to accompany him. In the house, Monty reveals this is supposed to be a Haunted House but "As a man of science, [Doc] doesn't believe in ghosts, right?". Doc replies that ghost were actually proven to exist in 2078, at which point blood starts leaking from the nearest door.


    Western Animation 
  • Often played for laughs on Futurama:
  • Time Squad is set in a future where there's no more war, no more pollution, humans have cracked time travel and bacon is good for your heart.


Example of: