Having read all the magazines I brought along to New Orleans, I was forced to purchase something for the trip home, Fortunately, I found The Swerve: How the World Became Modern by Stephen Greenblatt, which won the 2011 National Book Award for Non-Fiction.
Though Greenblatt tells his story in a much more engaging manner, I'll put this in a chronological order I can understand:
Building on the work of Democritus, who died a century before, Epicurus (d. 270 BC) founded a school of philosophy (Epicureanism) that is based on atomism, the idea that the universe is built from fundamental and invisible building blocks of matter flying through the void. (This some two millennia before the ideas could be tested in any form.)
Based on random "swerves," these atoms come together and apart to form everything from stars and planets to animals and humans. Nothing is eternal except these atoms, and no one form -- say, humankind -- is more important than another. They are not controlled by any external forces; i.e., gods. Thus, the gods -- though they may exist -- don't concern themselves with human actions and they do not reward and punish good and evil, which leaves humans to choose for themselves how best to live. For Epicurus this meant to seek pleasure and avoid pain, not in a hedonistic sense but by living a good and just life.
Jump forward a couple hundred years to Lucretius (d. 55 BC), who is basically known for one long Epicurean poem, De rerum natura, or On the Nature of Things. Almost nothing else is known of Lucretius's life or works, though his poem is held in high regard by his contemporaries.
The ideas in Epicureanism and On the Nature of Things are not held in high esteem as the world turns toward Christianity, and many classic works are forever lost both through suppression and neglect. The Christian authorities discredit Epicurus and Lucretius, inventing scandalous stories and creating the idea that Epicureanism entails an immoral quest for pure pleasure, a connotation still attached to the word 'epicurean'. In turn, the works are not copied by scribes and most of them disappear, their only existence brief mentions in other ancient works.
Jump now again to the early 15th Century, when the scribe and classicist scholar Poggio Bracciolini leaves his post as the pope's secretary in order to pursue his obsession: scouring the deteriorating libraries of European monasteries to find the few remaining works from Greek and Roman authors and arrange for their copy and distribution, thus helping to promote humanism. Poggio is the hero of The Swerve, but some of Greenblatt's stories are conjecture -- he possibly visited this monastery and likely spoke with that friar and probably found On the Nature of Things there, perhaps not even recognizing its importance.
It's this importance that Greenblatt wants us to understand, because he sees On the Nature of Things as a key work to spark the Renaissance, infecting the essays of Montaigne and possibly the plays of Shakespeare. Lucretius's beautifully written philosophy, you see, imagines a world free from religious fear, and entreats us to enjoy a pleasant life of good works, unconcerned with a highly scripted afterlife of eternal pain or reward. It is a signal work to help us break from years of church oppression and appreciate the universe in all its splendor, a place of beauty and art and ideas and happiness. Greenblatt even posits a link to Thomas Jefferson, who owned several copies of Lucretius and managed to write (the pursuit of) happiness into the Declaration of Independence.
Along with the journey of On the Nature of Things into the modern psyche, we learn about the life of Poggio, his navigation of some nasty politics in a time of three warring popes, the work of a medieval scriptorium, Poggio's importance to modern lettering style, even the construction of papyrus rolls and codexes. It's a great trip, and Greenblatt makes it an engaging tale.