Happy National Science Fiction Day, celebrating, among other things, the birthday of the brilliant writer Isaac Asimov.
Science fiction is an incredibly rich field of thinking and mode of thought. "[T]he task of science fiction is not to predict the future," says Eileen Gunn. "Rather, it contemplates possible futures." Chris McKitterick, Director of the Gunn Center for the Study of Science Fiction (University of Kansas), writes, "[M]ore than just a literary mode, SF is an ongoing conversation."
SF isn't merely a conversation about future, either (as McKitterick also notes). It's a thriving, dynamic conversation that regards multiple directions at once. Through SF, we envision, reimagine, and reconsider the past, present, and future. Speculation and social commentary are not restricted to any one point of what we might call our timeline. And that's one of the many beauties of science fiction.
For a great illustration of enduring SF themes in action — and just a really great way to celebrate a proper Science Fiction Day — take a look at the outer space voyage in one of the earliest Proto-SF works, Lucian's True History.