The subtitle of The Shallows, “What the Internet Is Doing to Our Brains,” introduces the focus of the text: the impact of the Internet on cognitive processes. Carr establishes precedent for intellectual technology’s influence on cognition through the examples of cartography, mechanical time keeping, and literacy. According to Carr, the development of the map and the clock had the same kind of transformative effect on cognition that the internet has today: “Every intellectual technology […] embodies an intellectual ethic, a set of assumptions about how the human mind works or should work” (45). New intellectual technologies don’t just serve as aids to thought; they actively change how humans think. Carr chronicles the long history of literacy technology—from cuneiform to typesetting—analyzing the shift from oral culture, with its focus on collective, experiential knowledge, to literary culture, with its focus on individual logic and reasoning. Alongside these shifts in culture are scientifically documented shifts in cognition. Widespread deep reading—uninterrupted reading of long printed text—encouraged widespread deep thinking, expanding people’s capacity for abstract, reflective thought. 

Carr argues that as the next evolution in intellectual technology, the Internet has a transformational effect similar to those of the book, clock, and map before it.