Mohs: Speculative Science

Speculative Science: Stories in which there is no "big lie" — the science of the tale is (or was) genuine speculative science or engineering, and the goal of the author to make as few errors with respect to known fact as possible.


Anime and Manga

Fan Fiction
  • Evangelion 303: This story makes a deliberate effort to be realistic. The science and engineering used is mostly pausible. Some of the technology (such like the anti-targetting field) is inexistent but feasible.
  • In Friendship Is Optimal, the only significant and most unrealistic change to technological progress is the invention of strong A.I. sometime around 2012. Much of the science is then extrapolated from current and theoretical future technology, albeit on a much faster scale since it's being done by an A.I. far more intelligent and capable than humanity.


  • The Martian by Andrew Weir is very accurate in regards to physics, chemistry, orbital mechanics, and botany, which is very impressive for an author with no background in an academic discipline.
  • The works set early in the timeline of Larry Niven's Known Space universe fall into this category, including Protector (which featured Bussard Ramscoops but no faster-than-light travel). The later in the timeline of Known Space you go, though, the farther the scale slides toward the soft side, with FTL, reactionless drives, inertialess drives, indestructible transparent hull material, and finally psychic luck all entering the fray.
  • Robert L. Forward's Rocheworld setting was quite hard through the first two books (it should be, he's a physicist). However, in the third and later books, the science softens to mush, including finding native coffee beans on the moon of a gas giant circling a red dwarf.
  • Dragon's Egg, also by Forward, takes the idea of life on the surface of a neutron star with extreme seriousness.
  • Robert A. Heinlein:
    • In The Moon Is a Harsh Mistress, except for Mike itself pretty much everything in the novel is already around, or could easily be put together in the next half-century (the book is set in 2075-2076). The only fly in jam here is that we had a moonbase for a minimum of thousands by the 90s.
    • The short story "The Menace From Earth" posits a sublunar colony that doesn't require a ton of future-tech but would be absurdly expensive to build with today's technology. Beyond that, the story sticks tightly to realistic extensions of the current technology. The protagonist is even engaged in drafting the design for a starship that anticipates engines that haven't been invented.
  • Charles Pellegrino's Flying To Valhalla and The Killing Star. The Valkyrie spaceships (and their alien equivalents) are a design seriously proposed by Pellegrino and Jim Powell. And, unfortunately, the major source of mayhem is pretty plausible too.
  • Steven Gould's Helm brings two major science-fiction elements: terraforming and technological brainwashing. The former is described in significant detail in an early chapter, and the terrain depicted of the book reflects the planet's history. The brainwashing is treated in less detail, but its mechanism of operation is convincing nonetheless.
  • John C. Wright's The Golden Oecumene trilogy, which has interstellar travel that respects the speed of light, and Count to the Eschaton, which is Space Opera set as hard an SF future as he could write.
  • The Quantum Thief-trilogy, written by Hannu Rajaniemi, an actual astrophysicist, tests the boundaries of the scale by applying the most advanced and uncertain theories in his field as well-known and practically applied everyday facts. Towards the end things start to get extremely crazy, as the possibility of using space-time itself as a quantum gravity computer is brought up. Breaking from the limits of causality and manufacturing new universes? Well, if some extremely exotic variations of the super string theory and the Many Worlds model are correct...
  • Most of the novels of Stephen Baxter, such as the Xeelee Sequence and Literature:Proxima, fall withing the softer edge of the spectrum, applying, similar to the Quantum Thief, advanced and uncertain theories in the field as well-known and practically applied everyday facts.

Tabletop Games
  • Quite neatly demonstrating that science fiction hardness is not perfectly correlated with plausibility: Car Wars. The only thing lifting it above Futurology on the Scale is the optional Body Backup Drive rules.

  • Person of Interest: The show is, for all intents and purposes, set in the present with the added existence of Artificial Intelligence, and as it goes on explores more and more the moral and geopolitical ramifications of its existence.

Video Games
  • I Miss the Sunrise is set far in the future, but doesn't rely on Applied Phlebotinum. Many of the technologies present are described in great detail and generally work according to real physics.
  • Most of Sid Meiers Alpha Centauri falls into this, with the technologies researched being based on genuine extrapolations and projections of current (theoretical) science; these are probably on the borderline with Futurology. The main exception is the Psychic Powers, but there are hints that there's a rational explanation for those, as well. Of course, all of this runs afoul of Gameplay and Story Segregation, but not that much.
    • The Alien Crossfire expansion pulls it further from this and towards Physics Plus: despite the fact that the Progenitors are Starfish Aliens, "resonance" is somewhat dubious as a possibility.

Web Comic
  • Deep Rise Almost everything is considered possible in principle by modern science.

Web Original
  • Orion's Arm falls at the softer end of this category. Things that are almost certainly impossible can be accepted but only so long as it is shown that they don't violate any known laws of physics. Wormholes that might violate causality undergo Visser collapse, extremely fast sub-light speed travel with Reactionless Drives has ridiculous amounts of math preventing violations of thermodynamics, brains the size of stars can be made but are subject to all the problems that come with it like light delay between different parts and the constant threat of turning into an actual star.

Futurology: Stories which function almost like a prediction of the future, extrapolating from current technology rather than inventing major new technologies or discoveries. Expect Zeerust in older entries.

Anime and Manga

  • Gattaca: Set in a very near future that introduces no really new technology but speculates on the advance of subtle human genetic manipulation and fetal selection and the ethical and social implications of a society that quickly relegates the non-engineered to second class status. The gamete selection technology portrayed in the movie is a reasonable extrapolation from technology that already exists; indeed, the furthest-out thing in the film is a manned expedition to Titan (and given an entire world population of geniuses, it's not much of a stretch except for the fact they don't wear spacesuits or seatbelts).

  • Red Mars by Kim Stanley Robinson, (as well as much of his other work) reads like genuine prophesy. Every single tool in Red Mars is carefully researched.
  • Given that The Machine Stops by E. M. Forster dates back to 1909, Zeerust is painfully evident throughout — but the idea of a globe-spanning information-processing system managing the delivery of food, operation of air travel, and aiding the dissemination of information is far from implausible, even if many of the details are distorted relative to what is now considered feasible.
  • Jules Verne did some of these, with Twenty Thousand Leagues Under the Sea and From the Earth to the Moon being the more oft-cited examples because major parts of their premises later came true, namely, the development of the submarine and the possibility to send space travelers to the moon through some sort of ballistic propulsion.
  • Stephen Baxter tends to write in this category, with books like Titan, about a mission to the moon using a combination of decommissioned Shuttle, ISS and Apollo technology.
  • Michael Flynn's Firestar series, a near-future setting about averting an asteroid that might otherwise hit the Earth.
  • Neuromancer, the William Gibson novel, falls on the hard side of the spectrum, largely because his vague depiction of Cyber Space has preventing it from aging too badly (although Zeerust abounds nevertheless). His description of the Freeside space colony is not too far off from what humans could realistically create in the near future, although it gets some of the details about Artificial Gravity wrong. Ironically, the most difficult thing in the novel to create in real life might be the AI itself that the title refers to.
  • Andy Weir's The Martian is extraordinarily hard sci-fi, with a focus on mechanical engineering, chemistry, NASA technology and procedure, and astrophysics.
  • In Outlander Leander, Nagdecht is a technologically advanced society, but almost everything they have could be recreated today or will be possible in the near future.

  • Max Headroom: Strongly related to its Twenty Minutes into the Future premise, though still spiced with the occasional TV commercial that makes people's brains explode. Which may be a comedic exaggeration of a Reverse Funny Aneurysm; certain TV shows have been known to trigger grand mal seizures.
  • ReGenesis: Set in the present, showcases bleeding edge biotechnology for its science fiction aspects (most of the technology featured are real or in the "theoretical possible but impractical/expensive/unethical stage of development)". Sometimes it's less science-fictiony than CSI.
  • TV docudramas about near-future space exploration, such as Space Odyssey Voyage To The Planets and Race to Mars.
  • Jupiter Moon, a British Sci-Fi series taking place on a decommissioned space vessel.
  • Star Cops, an earlier British series that, although not very successful with viewers or critics, remains one of the hardest TV SF shows ever written.

Tabletop Games
  • High Frontier aims to be a scientifically accurate simulation of the industrialization of the solar system in the near future. All the technologies available in the game are things that are feasible in the near future, and their statistics are as accurate as possible. An actual excerpt from the appendix:
To avoid the evaporation losses suffered by radiations that use liquid droplets in space, dust radiators use solid dust particles instead. If the particles are electrostatically charged, as in an electrostatic thermal radiator (ETHER), they are confined by the field lines between a charged generator and its collector. If the spacecraft is charged opposite to the charge on the particles, they execute an elliptical orbit, radiating at 1200 K with a specific area of 71 kg/m^2 and 213 kW_th/m^2. The dust particles are charged to 10^-14 coulombs to inhibit neutralization from the solar wind. Prenger 1982.

  • Deus Ex: Human Revolution revolves largely around the impact that cyborg technology would have on society and portrays such technology (and is socio-economic impact) rather realistically. Indeed what is most likely the series' most unrealistic point is the time frame; the series is set in 2027, while such technology in the real world will most likely take at least a decade more than that to develop.
  • Kerbal Space Program: Whilst largely based on existing technologies, the vanilla game does include plausible near-future tech such as single-stage-to-orbit Space Planes and manned interplanetary transport. There are many mods available, some of which push the tech level around the scale. Space Compression is used, but the proportions are accurate.

Back to Mohs Scale of Science Fiction Hardness.

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