Created by thousands of scholars and sold by door-to-door salesmen, a good set of encyclopedias once conveyed a sense of absolute wisdom on its reader. Now these huge books gather dust and sell for almost nothing; instead, we get our information from our phones and computers, apparently for free. What have we lost in this transition? Ranging from ancient Greece to Wikipedia, Simon Garfield candidly assesses how encyclopedias have reflected our changing attitudes towards sexuality, race, and technology, and considers mankind's quest for complete knowledge.