Let's start with this simple observation:
That literature is fundamental to our cultural heritage and our shared patrimony is a given. The Greeks have their Iliad and Odyssey, the Chinese their Tao te Ching, the Indians their Mahabharata, the Italians their Divine Comedy, the Spanish their Don Quixote, and each of these works is a literary masterpiece that is transcendent, every one an epic in the most fundamental sense of the word. Even among cultures that have not survived to our time, great works that helped define who these people were live on - the Mesopotamians with their Gilgamesh, the Persians with their Shahnameh, the Anglo-Saxons with their Beowulf, the Romans with their Aeneid, the Maya with their Popol Vuh, to cite just a few examples. But books not only define lives, civilizations, and collective identities, they also have the power to shape events and nudge the course of history, and they do it in countless ways. Some of them are profoundly obvious, as in the case of Harriet Beecher Stowe's Uncle Tom's Cabin, the 1852 novel that, some believe, moved Abraham Lincoln to remark, "caused this great war," or Rachel Carson's Silent Spring, an eloquent condemnation of the pesticide DDT issued in 1962 that questioned the sureness of technological progress and ushered in the environmental protection movement.