Still, what’s wrong with dreaming, right? In one sense, nothing. But in another, it matters how people with a lot of money dream. Bezos, Allen and Musk all have talked about their love of science fiction as part of their inspiration for investing in space. Bezos spent his summers reading authors such as Isaac Asimov and Robert A. Heinlein. Allen so loved his boyhood science-fiction collection that when he discovered that his mother had sold his books, he had the entire collection re-created.

As a former science-fiction geek myself, I can only sympathize. At its best, though, science fiction is a brilliant vehicle for exploring not the far future or the scientifically implausible but the interactions among science, technology and society. The what-if scenarios it poses can allow us to understand our own societies better, and sometimes that’s best done by dispensing with scientific plausibility. For example, Ursula K. Le Guin’s brilliant book The Left Hand of Darkness imagines an envoy from Terra (our Earth) to Gethen, a planet without fixed boundaries between genders. Through the hero’s encounter with an “ambisexual” species, we end up interrogating our own cultural norms around masculinity and femininity—groundbreaking for a book published in 1969.

Science fiction is sometimes denigrated as escapist literature, but the best examples of it are exactly the opposite. For me, it’s not the scientifically implausible part of science fiction that is most interesting. It’s what the expanded imagination allows us to discover about ourselves and our societies—and then to make them better.

Science and art have always been somewhat funded through the eccentric interests of the wealthy, and the combination has always been a mixed bag. One thing about being a billionaire is that it’s probably not hard to find people who will encourage you to spend money chasing space operas that either will not happen because of scientific constraints or will end up in disaster.

But more important, tech billionaires can shape our lives today, through how their companies operate, by repaying their obligations to society through taxes on their enormous wealth (at the moment, fairly little), and through their investments in solving the problems that threaten us. Doing that requires imagination. It’s just not the kind depicted on the covers of science-fiction books I, too, read as a child; it’s the kind that takes us to expanded universes only to have us think harder about how to understand the one inhabitable place for us in this vast universe—our fragile, pale blue dot—and make it a better place to live.