That innocent experience of the software upgrade—the relinquishing of control to something one does not understand or want to understand, consenting to a back-seat ride on sheer faith—is now a normal part of being a smartphone user, so normal that we scarcely notice it any longer. It is the sort of asymmetrical expertise one typically associates with a visit to the doctor—and it’s no surprise that apps hope to mediate that relationship as well.

How did we come to believe the phone knows best? When cultural and economic historians look back on the early 21st century, they will be faced with the riddle of how, in little more than a decade, vast populations came to accept so much quantification and surveillance with so little overt coercion or economic reward. The consequences of this, from the Edward Snowden revelations to the transformation of urban governance, are plain, yet the cultural and psychic preconditions remain something of a mystery. What is going on when people hand over their thoughts, selves, sentiments, and bodies to a data grid that is incomprehensible to them?