Those who don’t understand SF think it’s about robots, aliens, space travel, time travel, and other stuff of childish dreams that bear little relation to reality. I could write pages about how much past SF is infused into our very real present, but other writers have done it well already. And anyway, SF is about dreams—a very good thing.

SF is the most hopeful fiction there is.

SF is the fiction of human potential. It celebrates the extraordinary skills and abilities that the human species commands, which raise us above the level of other creatures. Old thinkers and empire builders acted as if our great abilities meant that humans were destined to subdue and dominate, but SF writers know the universe is too big a place for that. Instead, SF is about reaching barriers and overcoming them, one at a time, using every one of the gifts our race can muster. It’s about flights of technological fancy that we will someday make real, yes, but also about the drawbacks of those technologies and how we will overcome them.

When real life is dull and the immediate outlook is bleak, SF imagines bright futures in which problems have been solved, and continue to be solved through our ingenuity, energy, and sheer persistence. Often our own cherished scientific research presents us with doors that seem closed to us: the airless vacuum of space, the speed of light, the sheer size of the universe. But SF imagines keys to open those doors, or sometimes simply trusts that humankind will find a way as we’ve done so many times before. That’s hope.

SF can take us to some very dark places, often of our own creation: future worlds poisoned by our excesses, overrun by engineering run amok, dehumanized by dependence on technology, stifled by political bureaucracy at its hellish worst. Yet even these stories revolve around the human characters’ refusal to accept defeat and destruction. They are stories about invention, courage, self-sacrifice, and above all: hope. Even when they don’t end happily, their very existence as stories testifies to the writer’s hope that humanity can recognize such warnings and use our gifts to avoid the danger.

Occasionally SF even forecasts the end of humankind—at least, as we know it—whether because we change ourselves into something very different, artificial intelligence supersedes us, or some other species takes over. But still, SF is optimistic about Life itself, and its triumph over the dead matter of the cosmos.

SF educates, agitates, advises, and inspires. An article I read recently proposed that science fiction is important because it motivates great innovators to think big and to make imagined technology real. It also illustrates “the big picture”: the social implications of these new innovations, and where they might take the human race. If you want to understand the need for such inspiration to fuel human progress you should check out Project Hieroglyph, an online space “for writers, scientists, artists and engineers to collaborate on creative, ambitious visions of our near future.”

SF is important because it celebrates the human determination to overcome all obstacles. It’s about potential. It’s about hope. And who doesn’t want to be part of that?