"The Age of Surveillance Capitalism," Shoshana Zuboff, Public Affairs, 691 pages, $38.

In "The Age of Surveillance Capitalism," Shoshana Zuboff warns against mistaking the soothing voice of an Alexa or Google personal assistant for "anything other than the exploitation of your needs."

She likens the big tech platforms to elephant poachers, and our personal data to ivory tusks. "You are not the product," she said. "You are the abandoned carcass."

Zuboff, a professor emerita of Harvard Business School and the author of "In the Age of the Smart Machine" (1988), has a dramatic streak that could come off as simply grandiose if she didn't so painstakingly make her case in this extraordinarily intelligent book.

So many people take care to calibrate their privacy settings just so, sharing certain things with friends and keeping other things hidden, while their data still gets collected and shared among apps for possible monetization now or later.

Google and Facebook might not call to mind the belching smoke stacks and child laborers of the Industrial Revolution, but Zuboff argues that they are run by people who have turned out to be just as ruthless and profit-seeking as any Gilded Age tycoon. Instead of mining the natural landscape, surveillance capitalists extract their raw material from human experience.

Silicon Valley promotes an extreme form of entrepreneurial capitalism, unencumbered by any substantive responsibility to the communities that it purports to serve. Zuboff can get overheated with her metaphors, but then maybe reflexive discomfort only indicates an acclimation to the world that surveillance capitalists have created.