I was teaching Kim Stanley Robinson's wonderful novel Icehenge this week--it really is one of the great books. (Actually, I also--in another class--started teaching Samuel R Delany's Stars in My Pocket Like Grains of Sand, also from 1984--both books may well be better than Gibson's Neuromancer, but no matter how you slice it, it was a remarkable year for sf.) So, anyway, there at the end of the middle section, the narrator, Hjalmar Nederland, quotes the line that I've used as the title of this post.
One step ahead of (some of) my students, I typed it into Google, and found out it was the final phrase of this poem, by Rainer Maria Rilke. Now Hjalmar Nederland, in Robinson's book, is a sorry figure of a man, an academic archeologist incapable of having a successful human encounter. And he believes that archeology is the only route of action for a real, angry revolutionary like him, even while he's carrying on an affair with the spokesman for the Committee, which is who Nederland wants to overthrow with his archeological radicalism. And he busily searches the archives to prove the case he wishes to make, falls in love with a woman he knows only from a 300-year-old autobiography, goes on a solo expedition to the Martian outback to try to find her, and nearly kills himself in the attempt. And he comes back and quotes Rilke to himself: "You must change your life."
And, as far as we ever know, he never manages to change his life. And I certainly hope I'm not a Hjalmar Nederland (medievalist vs. archeologist--no comparison!). But man, changing your life. That's a tall order, archaic torso of Apollo.