The genre of science fiction itself is difficult to define. Often science fiction contains the common themes of aliens, other nonhumans, time travel, artificial intelligence, humans destroying themselves, etc. Science fiction texts are usually based in reality, but they explore how far reality can be stretched. Science fiction is not fantastical, but deals with themes and plots that are plausible, even if far-fetched, and which push the limits of technological advancement. The genre invites questions about humanity and the world, and often raises moral and ethical issues.
Many science fiction texts are speculative. They do not necessarily push scientific or technological boundaries, but they still imagine different worlds. Station Eleven, for example, does not contain any aliens, time travel, or other "classic" science fiction components, but instead it takes place in our world as it is, but which has been radically altered by a devastating flu pandemic. The poem "The Quiet World" could also be considered speculative. It imagines a world which is entirely different from the one in which we live now because of actions by the government. Although these two texts do not have overtly "science-y" elements, they raise important questions about humanity which are prevalent and important in science fiction texts.
There are speculative components in all science fiction texts: theoretically, humans could develop a means of cloning one another for medical purposes (Never Let Me Go), humans could create humanoid robots which eventually develop intelligence greater than humanity's itself (Do Androids Dream of Electric Sheep?, Battlestar Galactica), or humanity could destroy itself entirely ("There Will Come Soft Rains," "The Monsters are Due on Maple Street").
Ultimately, whether described as science fiction or speculative fiction, these texts are interested in issues and themes which are perpetually relevant to humanity. Among those themes, which I engage with in this concept map, are survival, technology, memory, fear, agency, power, gender, and equality.