“Present Shock” is one of those invaluable books that make sense of what we already half-know. Playing on the title of Alvin Toffler’s influential 1970 “Future Shock,” which sounded an alarm about what Mr. Toffler called “a personal perception of too much change in too short a period of time,” Douglas Rushkoff analyzes a very different phenomenon. The future arrived a little while ago, he posits — maybe with Y2K, maybe with Sept. 11. Now it’s here. And we are stuck with “a diminishment of everything that isn’t happening right now — and the onslaught of everything that supposedly is.” Mr. Toffler warned that we would be unready for this onslaught. Mr. Rushkoff is more analytical than alarmist. He divides his thoughts into five sections addressing five kinds of profound change, and his biggest illustration of present shock has to do with the actual book itself. Because the present is more full of interruptions than the past was, it took him extra time to write. Because its ideas aren’t glib, he says, “here I am writing opera when the people are listening to singles.” And he realizes that data-swamped readers may take longer to finish books now. Coming from him the phrase “thanks for your time” has new meaning.

“Present Shock” begins by simply describing how we have lost our capacity to absorb traditional narrative. It goes on to explain what we have used to replace it. There was a time, Mr. Rushkoff says, when everything had narrative structure, even TV ads. Captive audiences sat through commercials that introduced a protagonist, presented a problem, then pitched a product to solve it. The little story ended well, at least from the advertiser’s point of view. But now viewers may be more angry than bored at such intrusions. They know that “someone you don’t trust is attempting to make you anxious,” so they ditch the ad before it’s over.

The ancient Greeks learned about the hero’s journey from Homer’s narratives. We’ve gotten decades of Homer Simpson, who “remains in a suspended, infinite present,” while his audience moves from one satirical pop-culture reference to the next. Citing “Forrest Gump” as a film that failed to combat late-20th-century feelings of discontinuity and “Pulp Fiction” as one wild enough to usher in a new era, Mr. Rushkoff moves on to what came next: the video game open-ended structure that keeps TV drama in the eternal present. About “Game of Thrones” he says, “This is no longer considered bad writing.” Changes to news presentation are even more dramatic. This book describes the present shock of politicians who — thanks to the 24/7 coverage ushered in by “the CNN effect” that began in the 1980s — “cannot get on top of issues, much less get ahead of them.” He notes that both the political left (MSNBC, with its slogan “Lean Forward”) and right (conservatism devoted to reviving traditional values) share this goal: They’re trying to escape the present.