Physical Memories in a Digital World

On the paradoxical blend of permanence and impermanence in digital documents

The more than 7,200 pages now extant probably represent about one-quarter of what Leonardo actually wrote, but that is a higher percentage after five hundred years than the percentage of Steve Jobs's emails and digital documents from the 1990s that he and I were able to retrieve.

—Walter Isaacson, Leonardo da Vinci

This was a striking line from Walter Isa…