Twenty-three hundred years ago, the legend goes, King Ptolemy I of Egypt asked his court adviser to assemble a comprehensive collection of the world’s written works. Ptolemy, who had served under Alexander the Great, envisioned a library that would safeguard the sum total of humanity’s knowledge. His successors inherited this mandate. Royal forces ransacked every ship that arrived at Alexandria, searching for scrolls. These were stored at the Mouseion, a shrine to the Muses modeled after Aristot