List of science fiction themes
The following is a list of recurring themes in science fiction. Please note this list also includes themes you'd also find in other genres.
Overarching themes
- Cosmology
- Creation of the Universe
- The future
- History
- Alternate history
- Historical cycles: history repeating itself (either on long or short scales)
- Scientific prediction of the future (e.g. psychohistory)
- Secret history
- Horror fiction
- Language
- Alien languages (e.g. Klingon, Huttese)
- All humans speaking one language (possibly Esperanto)
- Current human languages evolving/splitting
- The Sapir-Whorf Hypothesis being strongly true (e.g. Babel 17 by Samuel R. Delany or The Languages of Pao by Jack Vance)
- Universal Translators (e.g. Babel fish)
- Military - strategy, weapons, ranks, technologies.
- Omega Point
- Quantum suicide and immortality
- Parallel worlds or universes.
- There is a space based civilization variant of this theme. This plot device allows writers to write soft science fiction while accounting for the lack of technological advancement and thus similarity to the present day.
- Religious ideas in science fiction
- Sci fantasy
- Sex (including gender roles, polygamy, sexuality and procreation)
- Sociology and sociobiology
- Space Opera
Types of beings
- Alternate intelligences
- Artificial intelligence
- Beings of pure mentality
- Hive minds
- Infomorphs - memories, characters and consciences of persons being uploaded to a computer or storage media
- Noosphere - the "sphere of human thought"
- Solipsism & Solipsism syndrome - a belief that the universe is entirely the creation of one's own mind
- Androids and Gynoids
- Characters
- The Absent-minded professor or Monomane & Eclecticism
- The Detective
- The God-Like Alien
- The Golem
- The Ignorant Friend
- Redshirt
- The Robot Clone
- The Robot Servant
- The Scientist
- The Mad Scientist
- The Amoral Scientist
- The Heroic Scientist
- The Lame Amoral Scientist
- The Wedge
- Clones
- Extraterrestrial life (see Extraterrestrial life in culture)
- Alien invasion
- Astrobiology
- Benevolent aliens
- First contact
- Principles of non-interference (e.g. Prime Directive)
- Living Planets
- Mutants
- Shapeshifters
- Superhumans
- Symbionts
- Uplifted animals - using technology to "raise" non-human animals to human evolutionary levels
Body and mind alterations
- Bio-implants
- Body modification, including genetic modification
- Bionics
- Cybernetics
- Intelligence amplification
- Invisibility
- Life extension, Biological immortality, Universal immortalism and immortality
- Artificial organs
- Cloning
- Cryonics
- The Organ Bank Problem - a proposed problem in which the reduced death rate caused by organ transplants would lead to a shortage of organs available for transplant
- Mind interfacing
- Memory removal/editing
- Mind control
- Mind uploading
- Neural implants to directly interface with machinery
- Molecular manufacturing & Nanotechnology (nanomilitary, nanomaterials, nanoecology, nanomedicine, nanocomputing, nanospace, nanoenergy)
- Psi powers and psychic phenomenon
- Paradise engineering
- Resizing (size-changing, miniaturization, magnification, shrinking, and enlargement)
- Shapeshifting
- Telepathy
- Teleportation
Possible futures
- Alien invasions
- Apocalypses or world wide disasters
- Post-apocalyptic life - new societies that develop after the event
- Posthumanism
- Race of the Future
- Ultimate fate of the Universe & Kardashev scale
Political structures
- Alien Contact
- Anarchism
- Anarcho-capitalism (see: Anarcho-capitalist literature and Libertarian science fiction)
- Assassination
- Astrosociology
- return to feudalism
- hive-like eusocial societies
- future caste systems
- Capitalism
- Dystopias and utopias
- Environmentalism
- Science fiction is used to raise awareness of environmental ideas. Lends itself well to dystopian futures. Frank Herbert and Kim Stanley Robinson are known for their serious concern with ecological issues.
- Economics
- Eugenics
- Fascism
- Galactic empires
- Interstellar federation of planets
- Legal personality
- Libertarianism
- Limited-franchise republic
- Militarism
- Mind reading and mind control
- National security state
- Nepotism
- Pacifism
- Plutocracy
- Proportional representation
- Racism
- Revolution
- Slavery
- Socialism
- Theocracy
- Totalitarianism vs. Libertarianism (see: Libertarian science fiction)
- Treason
- World government
- Zero population growth
Habitats
- Alien Reality Television, usually the protagonist discovers his life has been one big reality television show for aliens.
- Alien Zoo, a zoo where humans are kept as exhibits.
- Arcologies - enormous habitats (hyperstructures) of extremely high human population density
- Domed city
- Endemic
- Exploring alien habitats.
- Floating City
- Seasteading & Ocean colonization
- Space colonization
- Underground city
- Walking City
Travel
- Colonization of other planets, moons, asteroids, etc.
- Moving planets
- Space exploration
- Interstellar travel
- Faster-than-light travel and communications
- Much slower than Light
- Very nearly light speed
- Bussard ramjets
- Ursula LeGuin's NAFAL ships, and the Twin paradox
- Space stations
- Interstellar travel
- Time travel
- Alternate histories: time travel can be used as a plot device to explore parallel universes. While alternate history has its own category (see above), it often occurs in time travel stories as well.
- Anachronism
- The Grandfather paradox -- e.g. Can someone go back in time and kill his parents before they beget the killer?
- Travel to the Earth's center
Technologies
- Artificial gravity
- Artificial intelligence
- Singularity
- Star lifting & Stellar engineering
- Megascale engineering & Planetary engineering
- Technology
- Far advanced technology for the time.
- Alien technology being found and used by humans. Most of the time for selfish purposes, or is being used incorrectly (not how it's supposed to work)
- Virtual reality and simulated reality
- Weapons