But buried in Songdo’s millions of sensors is more than the promise of monitoring energy use or traffic flow. The city’s “Ambient Intelligence,” as it is called, is the latest iteration of a ubiquitous computing revolution many years in the making, one that hopes to include the human body among its regulated machines. More than a decade ago, Philips Electronics published a book called New Nomads, which described prototypes for wearable wireless electronics, seamlessly integrated into clothing, which would effectively turn the human body into a “body area network.” Today, researchers at M.I.T.’s Human Dynamics Lab have developed highly sensitive wearable sensors called sociometers that measure and analyze subtle communication patterns to discern what the researcher Alex Pentland calls our “honest signals,” and Affectiva, a company that grew out of M.I.T.’s Media Lab, has developed a wristband called the Q sensor that promises to monitor a person’s “emotional arousal in real-world settings.”

Now we can download numerous apps to our smartphones to track every step we take and every calorie we consume over the course of a day. Eventually, the technology will be inside of us. In Steven Levy’s book In the Plex, Google founder Larry Page remarks, “It will be included in people’s brains ... Eventually you will have the implant, where if you think about a fact it will just tell you the answer.” The much-trumpeted release of the wearable Google Goggles was merely the out-of-body beta test of this future technology.

Now that we feasibly can embed electronics in nearly any object, from cars to clothing to furniture to appliances to wristbands, and connect them via wireless signals to the World Wide Web, we have created an Internet of Things. In this world, our daily interactions with everyday objects will leave a data trail in the same way that our online activities already do; you become the person who spends three hours a day on Facebook and whose toaster knows that you like your bagel lightly browned. With the Internet of Things, we are always and often unwittingly connected to the Web, which brings clear benefits of efficiency and personalization. But we are also granting to our technologies new powers to persuade or compel us to behave in certain ways.

TECHNOLOGY IN PRACTICE is nearly always ahead of technology in theory, which is why our cultural reference points for discussing it come from science fiction rather than philosophy. We know Blade Runner and not Alfred Borgmann, HAL and not Heidegger. We could even view the city of Songdo through the lens of “The Life and Times of Multivac,” Isaac Asimov’s story, from 1975, about a supercomputer that steps in to run society smoothly after human missteps lead to disarray. But our tendency to look to fictional futurist extremes (and to reassure ourselves that we have not yet overstepped our bounds) has also fueled a stubbornly persistent fallacy: the idea that technology is neutral. Our iPhones and Facebook pages are not the problem, this reasoning goes, the problem is how we choose to use them. This is a flattering reassurance in an age as wired as our own. In this view, we remain persistently and comfortably autonomous, free to set aside our technologies and indulge in a “digital Sabbath” whenever we choose.