Direct Descent Lib/E by Herbert, Frank

A library planet: the greatest treasure, the deadliest weapon

Earth has become a library planet over the last several thousand years, a bastion of both useful and useless knowledge-esoterica of all types: history, science, politics-gathered by teams of pack rats who scour the galaxy for any scrap of information. Knowledge is power, knowledge is wealth, and knowledge can be a weapon. As powerful dictators come and go over the course of history, the cadre of dedicated librarians is sworn to obey the lawful government-and use their wits to protect the treasure trove of knowledge they have collected over the millennia.