Aliens. Monsters. Robots. Spaceships. Superhuman powers. Time machines. Yup, we're talking science fiction. But just why are these ideas so perennially popular?

As scholars and creators of the genre told, many of sci-fi's common scenarios, which may seem to be escapist fantasy, serve to delve into complex themes that beholden-to-reality fiction and nonfiction cannot explore so readily.

By engaging in what-ifs that are either far-out and close to home, science fiction stories can challenge assumptions that otherwise would go unexamined. Sci-fi shows us through film, television and literature where our society might have ended up, for better and for worse, had things been different.

"On a basic level, sci-fi is so appealing across media because it's the premier storytelling form of modernity," said Lisa Yaszek, a professor of literature, communication and culture at the Georgia Institute of Technology who is current president of the Science Fiction Research Association.

"We live in a world so profoundly shaped by new sciences and technologies and the new realities they enable. Sci-fi is the one genre that has all these story and character types set up to explore these questions," she added. [Quiz: Are you a Sci-Fi Fan or Faker?]

Science fiction categories

Yaszek described three very broad categories of science fiction that together explore the thought experiment landscape of the genre: the creation story, the fantastic voyage, and what she calls the "domestic science fiction story." (Naturally, these themes often overlap in individual tales.)

The first category, as its name implies, runs the gamut from stitching together a quasi-human from corpse pieces (Mary Shelley's "Frankenstein") to building robots that have artificial intelligence ("Battlestar Galactica," among many examples).

The second basic type of sci-fi story, the fantastic voyage, often involves "brave, scientist-type explorers who go to where humans don't usually live," said Yaszek. Obvious instances include "Star Trek" and Jules Verne's "20,000 Leagues Under the Sea."

The third category, domestic science fiction, consists of stories "about our encounters with new science and technology in our daily lives," said Yaszek. "We can talk about spaceships all we want, but so many of our fantastic voyages begin in the home where most of us actually experience science and technology."

Examples of domestic sci-fi include stories found in the sub-genre of cyberpunk that emerged alongside personal computers in the early 1980s, epitomized by William Gibson's "Neuromancer" and seen more recently in "The Matrix" franchise. [Best Science Fiction TV Shows Ever]

Through the prism of sci-fi

In many instances, science fiction serves as a vehicle for controversial topics of an era, from industrialization's dehumanization and environmental toll in the late 19th century to the specter of nuclear war in the mid-20th century and to the "war on terror" over the past decade.

"Putting things in sci-fi tropes can enable you to do exactly the same end run that Aesop did in fables," said Diane Duane, an author of science fiction and fantasy books and teleplays. "You can distance the more controversial material you might be trying to deal with by pushing it 300 years into the future or into [the] past via a time machine, and you are more free to examine the material closely, and the reader doesn't feel as threatened."

Accordingly, science fiction can provide windows into social codes of conduct, Yaszek said. Characters may have to cope with, say, the cultures of extraterrestrials or the philosophical ramifications of sentient machines, or individuals with abilities and differences à la the X-Men. These works can say a lot about how people deal with those they consider "other," whether in dress, skin tone or morals.

For Nebula Award-winning author Jack McDevitt, this confrontation with the "other" inspires much of his work. "My prime interest in science and science fiction is aliens," McDevitt told "If we ever discover there is someone else out there, how do we react as a society?"

The alien in the mirror

Fans and creators share McDevitt's fascination: Some of science fiction's best-known stories, from H.G. Wells' "The War of the Worlds" to the silver screen's "The Day the Earth Stood Still" to television's "V," involve hostile alien visitations.

Other classics, from "Contact" to "Close Encounters of the Third Kind," put the protagonists face-to-face with benevolent beings from elsewhere in the cosmos.

For science fiction short-story writers, narratives involving first contact with extraterrestrials have been the surest route to publication, according to a review of nearly 2,000 pulp stories that appeared in American magazines between 1926 and 2000.

Those stories most likely to be reprinted, however, are those that take on headier themes, such as satirizing a dystopian society, according to Eric Rabkin, a professor of English and literature at the University of Michigan.

"Although the most frequently published science fiction stories are often interested in exploring a situation of newness, the science fiction stories with continuing value were less likely to be about confronting the 'other' than they were about fixing society," said Rabkin, co-leader of the Genre Evolution Project, which is studying pulp science fiction short stories as a complex adaptive system.

Given the pace of change enabled by science and technology in the last couple of centuries, it's little wonder that sci-fi has emerged as a genre that holds up a mirror to the present by looking ahead to the future.

Where we're heading

Science fiction is often predictive, or extrapolative. It will take certain aspects of the here-and-now and will project from them. Dealing with fertility and reproductive science, for example, the 1997 film "Gattaca" presents a future society that tinkers with the genetic code to produce designer babies.

In an introduction to her Hugo- and Nebula Award-winning 1969 novel "The Left Hand of Darkness," Ursula K. LeGuin argued against the stereotype of science fiction as merely predicting the future; rather, LeGuin dsid she saw the genre of science fiction (and all fiction, for that matter) as metaphor for things in our present era.

What sets science fiction apart from older forms of fiction, she wrote, "seems to be its use of new metaphors, drawn from certain great dominants of our contemporary life – science, all the sciences, and technology, and the relativistic and the historical outlook. Space travel is one of these metaphors; so is an alternative society, an alternative biology; the future is another."

Yaszek believes science fiction "ultimately is a positive genre; it believes rational humans can work together and use science and technology to improve the world."

In this way, even the dystopias common to science fiction – nuclear weapon-annihilated civilizations, warring human factions spread amongst the stars, machine overlords subjugating humanity – essentially have a positive role, Yaszek said, as "cautionary tales."

This article was reprinted with permission from

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