Science Fiction (Sci-Fi) is the genre that discusses and displays stories in alternate realities by presenting the author’s vision of answers to three questions:
1) What if? 2) What could happen? 3) Why and how? (optional)
First, by considering and answering the question of “what if,” the author provides the setting that differs from the daily reality to innovate or change one or multiple ordinary storytelling elements as time (when), place (where), species or characters (who and whom), and events (what) via techniques like defamiliarization and displacement. For example, tons of Sci-Fi works involve changing the setting of time, while Xeno works innovate new species, and these two also can happen simultaneously in one piece. Note that not all Sci-Fi works are about the future: Gravity’s Rainbow (1973) sets at the end of WWII, Counterpart (2017) mixes the present and the 1970s, and The Man From Earth (2007) is from 14,000 years ago to the present. Answers to this question are blocks constructing the foundation of alternate realities because they create preconditions and motivations for answering the second question.
Then, the author needs to develop and describe the consequences of innovative or changed elements: What could happen in 2049? –Humans could live with androids. What could happen if there were aliens? –They may plan to colonize Earth. In this way, stories in alternate realities are basically complete.
Furthermore, it is optional to answer the question of “why and how these could happen” by scientifically and rationally explaining the reasons for and causes of these consequences. If there are scientifically possible explanations of the principles and processes underlying the alternative setting and consequences, it is a hard Sci-Fi work; otherwise, it can be a soft Sci-Fi. Additionally, the categorization of many soft Sci-Fi works is controversial and confusing. For instance, it is hard to determine whether some works containing zombies or Cthulhu belong to Sci-Fi due to their insufficient logical explanations of the sources and causes of these monsters.
Therefore, Sci-Fi authors’ answers to these questions contribute to Sci-Fi’s key feature and charisma: the combination of the fantastic imagination of vivid scenarios and the logical development of alternate realities.