Remember Douglas Adams’s 1979 novel “The Hitchhiker’s Guide to the Galaxy”? It began with some technology snark, dismissing Earth as a planet whose life-forms “are so amazingly primitive that they still think digital watches are a pretty neat idea.” But that was then, in the early stages of the information technology revolution.

Since then we’ve moved on to much more significant things, so much so that the big technology idea of 2015, so far, is a digital watch. But this one tells you to stand up if you’ve been sitting too long!

O.K., I’m snarking, too. But there is a real question here. Everyone knows that we live in an era of incredibly rapid technological change, which is changing everything. But what if what everyone knows is wrong? And I’m not being wildly contrarian here. A growing number of economists, looking at the data on productivity and incomes, are wondering if the technological revolution has been greatly overhyped — and some technologists share their concern.

We’ve been here before. “The Hitchhiker’s Guide” was published during the era of the “productivity paradox,” a two-decade-long period during which technology seemed to be advancing rapidly — personal computing, cellphones, local area networks and the early stages of the Internet — yet economic growth was sluggish and incomes stagnant. Many hypotheses were advanced to explain that paradox, with the most popular probably being that inventing a technology and learning to use it effectively aren’t the same thing. Give it time, said economic historians, and computers will eventually deliver the goods (and services).