Over the last few millennia, we've invented a series of technologies … that have made it progressively easier and easier for us to externalize our memories, for us to outsource this fundamental human capacity.

Foer is pointing to a long historical arc in which tools—from writing and books to photographs, computers, and networked search—shift memory from an internal, trained skill to something stored outside the mind. The quote frames “outsourcing” memory as both a convenience and a cultural trade-off: as external records become more reliable and searchable, individuals may feel less pressure to practice recall, potentially changing how attention, learning, and identity work. Implicitly, he invites readers to ask what is lost when remembering becomes a matter of retrieval rather than reconstruction—whether cognitive resilience, depth of understanding, or the personal meaning that comes from holding knowledge in one’s head.