Back in 2003, I noted that when future-setting sf characters refer to “an ancient Terran word,” they nearly always mean “a 20th-century American English word.”
I've been meaning for some time to expand that observation to cover more than just words.
For example, when sf characters refer an “an old Terran tradition,” they're generally talking about a 19th- or 20th-century upper-middle-class white American or British tradition.
When they mention an “old Earth religion,” it's usually Christianity, generally Catholicism or a mainstream Protestant denomination.
When they quote an “ancient human writer,” it's usually a famous British poet or playwright of the 16th to 19th centuries. A “philosopher from Old Earth” might be one of the American Founding Fathers.
Or sometimes they refer to Classical mythology and stories, but only the stuff that's widely known in modern American culture, like the Trojan Horse.
Or once in a while, as a joke, the thing that's referred to is some piece of current pop culture—the interstellar civilization of the future is a big fan of Friends or American Idol or something. Or science fiction; the Great Ancient Philosopher they're talking about might be Heinlein.
In other words: the remnants of human culture that survive into the far future are generally the things that modern white upper-middle-class American science fiction writers think of as currently famous or well-known or influential.
So, writers (especially white American writers, who I suspect are the ones most prone to this): next time you're going to have your future-sf characters refer to something from old Earth history, consider drawing from sources other than the kinds of sources mentioned above. You could have them quote the Ramayana and the Mahabharata, for example. Or the Eddas. You could draw on famous Chinese thinkers or famous Russian writers. If you want a joke reference to modern TV, you could refer to telenovelas. You could mention an ancient Terran religion that comes from Africa, or an Old Earth tradition that derives from Israel.
This is, of course, all a subset of the general topic of making your futures multicultural, which is a subset of the even more general topic of Writing the Other. And it's a tiny minor thing, and it doesn't come up all that often. It's probably not worth the verbiage I'm devoting to it.
But I think part of why it jumps out at me is that it is such a small thing. It's usually just a throwaway line in passing. So to some degree it has the potential to be an easy way to start to lend your story a little bit of multicultural depth.
I mean, if your future culture is 100% modern American in all other ways, then this won't help. But broadening your story's cultural references might be an easy first step toward opening the doors to some other possibilities.
(Wrote this entry in October of 2011, but never published it.)