E X T E N S I O N SCIENCE FICTION General characteristics Stories which take place in the future or in which the contemporary setting1 is upset2 by an imaginary device, such as a new invention or the introduction of an alien, are the main themes of the literary genre called science fiction. When the novel was born (early 18th century), the possible worlds of literature became more or less the same as those of the real world of the reader, as opposed to the fantastic and unrealistic style of traditional romance3. in a way, science fiction makes use of the fantastic trend4 of literature. it creates a possible world based on logical principles which do not apply to ours. Sometimes, physical or biological laws may be different as well, as in the case of aliens, whose physical aspect and movement can be very different from humans. Science fiction often refers to scientific laws which are imagined rather than real, but in any case they reflect the role of science in modern culture. the main difference between fantasy and science fiction (see also extension 1) is that, while fantasy is usually set in a mythical past, science fiction is based on scientific and technological principles and takes place in a hypothetical future. 1. setting: location. 2. upset: disturbed. 3. romance: a prose narrative treating imaginary characters involved in events remote in time or place and usually heroic, adventurous or mysterious. 4. trend: tendency. 32