Science fiction has a number of common concepts and themes that have been reused by numerous authors. Some have become cliches, and only truly novel treatments of them gain attention, whilst others have become "part of the furniture"—they can be included in a story without much explanation because readers are already familiar with the core concept.
ArcologiesAn arcology so far only existing conceptually (with experiments taking place at Arcosanti), is an extremely large building, sufficient to maintain an internal ecology as well as an extremely high human population density. Popular in science fiction, arcol
Artificial intelligenceThis article is about modelling human thought with computers,. For other uses of the term AI see Ai''. Artificial intelligence also known as machine intelligence is defined as intelligence exhibited by anything manufactured (i. artificial) by humans or ot
von Neumann machineA von Neumann machine is a model created by John von Neumann for a computing machine that uses a single storage structure to hold both the set of instructions on how to perform the computation and the data required or generated by the computation. Most mos
CloneThe term clone is derived from kappa;λω&nu the Greek word for "twig". In horticulture, the spelling clon was used until the twentieth century. The final e came into use to indicate the vowel is a "long o" instead of a "short o"; see the refers
TerraformingMichael Carroll) Terraforming (literally, "Earth-shaping") is the process of modifying a planet, moon or other body to a more habitable atmosphere, temperature or ecology. It is a type of planetary engineering. The term is sometimes used very broadly as a
CosmologyCosmology is the study of the large-scale structure and history of the universe. In particular, it deals with subjects regarding its origin and evolution. It is studied by Astronomy, Philosophy, and Religion. See also cosmogony. Subjects in cosmology incl
Science Fiction is used to raise awareness of Ecological ideas. Lends itself well to dystopian futures. Frank Herbert and Kim Stanley Robinson are known for their serious concern with ecological issues.
"Age of Greater Scarcity", often in connection with ecological or post-apocalyptic themes. In such dystopias, people are poorer and have fewer resources to draw on.
Post-"Age of Scarcity" (arguments over how to distribute resources are irrelevant since anyone can have anything they reasonably want). Examples include:
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.
Alternate history: time travel can be used as a plot device to explore parallel universes. While alternative history has its own category (see above), it often occurs in time travel stories as well.
