Sometime in the summer of 2020, I noticed an occasional, searing pain shooting up my right forearm. It soon became clear this was a byproduct of a gesture that had become as commonplace as breathing or blinking that season, if not long before: scrolling. This was how I spent most of the day, it seemed. Smartphone welded to my palm, thumb compulsively brushing upward, extracting content out of the empty space beneath my phone charger port, pulling an endless succession of rabbits out of hats, feverishly yanking the lever on the largest and most addictive slot machine in the world. The acupuncturist I saw to help repair my inflamed tendon implored me to stop, so I did, for a while—I just awkwardly used my left index finger instead.

Of course, it wasn’t always this way. While a desktop computer has its own hazardous ergonomics, the experience of being online was once far more “embodied,” both literally and conceptually. Interfacing with a screen involved arms, hands, and fingers all in motion on clacking keyboards and roving mice. Accordingly, the first dominant metaphors for navigating digital space, especially the nascent World Wide Web, were athletic and action-oriented: wandering, trekking, and most of all, surfing. In the 1980s and ’90s, the virtual landscape of “cyberspace” was seen as just that, a multidimensional “frontier” to be traversed in any direction one pleased (with all the troubling colonial subtext that implies), echoed in the name of browsers like Netscape Navigator and Internet Explorer. As media scholar Lev Manovich argues in his 2002 book The Language of New Media, by the early 1990s, computer media had rendered time “a flat image or a landscape, something to look at or navigate through.”

But when the screens became stowaways in our purses and pockets, this predominant metaphor, however problematic, shifted. Like the perspectival evolution that occurred when frescoes affixed to walls gave way to portable paintings, shrinking the screen down to the size of a smartphone altered the content coming through it and our sense of free movement within it. No longer chairbound behind a desktop, we were liberated to move our actual bodies through the world. Meanwhile, that sense of “surfing” virtual space got constrained to just our fingertips, repeatedly tapping a tiny rectangle to retrieve chunks of content.

A user could “scroll” through l...