"One of the world's most celebrated scholars, Stephen Greenblatt has crafted both an innovative work of history and a thrilling story of discovery, in which one manuscript, plucked from a thousand years of neglect, changed the course of human thought and made possible the world as we know it.

"Nearly six hundred years ago, a short, genial, cannily alert man in his late thirties took a very old manuscript off a library shelf, saw with excitement what he had discovered, and ordered that it be copied. That book was the last surviving manuscript of an ancient Roman philosophical epic, On the Nature of Things, by Lucretius — a beautiful poem of the most dangerous ideas: that the universe functioned without the aid of gods, that religious fear was damaging to human life, and that matter was made up of very small particles in eternal motion, colliding and swerving in new directions.

"The copying and translation of this ancient book — the greatest discovery of the greatest book-hunter of his age — fueled the Renaissance, inspiring artists such as Botticelli and thinkers such as Giordano Bruno; shaped the thought of Galileo and Freud, Darwin and Einstein; and had a revolutionary influence on writers such as Montaigne and Shakespeare and even Thomas Jefferson."

Interviewer: Describe how you came upon the central text on which The Swerve is based, Lucretius' poem "On the Nature of Things."

Stephen Greenblatt: I came upon the poem quite by accident, randomly browsing through the bins of marked-down books at the end of the year in my college bookstore. I paid 10 cents for it — I have the paperback still.

Interviewer: What drew you to the material?

SG: I was initially drawn by the cover image, a startling detail from a painting by the surrealist Max Ernst. But I was immediately struck by the poem's intensity, by its eerie modernity, and by its therapeutic words about the fear of death.

Interviewer: You mention in the book that Bracciolini's letter describing his account of finding the poem was lost. How did you go about reconstructing that event, and why did you feel it was necessary?

SG: The letter about that particular discovery is lost, but many other letters between Poggio Bracciolini and his humanist friends survive. Those were a great help, along with the results of several centuries of intensive research by dedicated scholars and bibliophiles. I also personally visited monasteries in Italy, Switzerland, and Germany. Why? Because the recovery of the lost poem is both an instance and an emblem of everything we mean by the term "Renaissance."

Interviewer: How did you go about weaving together the stories of Lucretius and Bracciolini (and, to some degree, your own narrative)?

SG: This was in fact a great challenge and took a crazy amount of work. The principal problem was balance, and I wound up — for the first time in my writing life — throwing out quite a lot that I had labored to research and to write.

Interviewer: Lucretius was a poet who thought deeply about science. How do you think Lucretius would have reacted to the refutation of his ideas that "worms were spontaneously generated from the wet soil," and "the sun circled around the earth"?

SG: Lucretius and the philosophical school of which he was an adherent were dogmatic about the existence of atoms and emptiness and nothing else. But they were not dogmatic about their speculative scientific explanations of particular phenomena — earthquakes, for example, or lightning, or plague. What was important for them was to understand that such things had natural causes — that they were not the results of divine punishment. At several points Lucretius concedes that he does not fully understand the natural cause, but he insists that one exists. I think then that he would have accepted the refutation graciously. He would, I suspect, have had more trouble dealing with "dark energy" and "dark matter." But then I don't know what to make of these myself!

Interviewer: "On the Nature of Things" argued for the pursuit of joy by the living, and was suppressed after it was rediscovered by Bracciolini. What are your thoughts on how ideas survive despite campaigns of idea suppression, book burnings, and the like?

SG: The "pursuit of joy by the living" is one of the principal motives of existence — it springs up naturally in the most uncongenial environments, as the grass springs up in the cracks of the sidewalk. Suppression and burnings were focused principally on those Christian contemporaries who embraced for themselves ideas deemed heretical — the simple existence of those ideas in works by pagans who lived before the time of Christ was not the object of active persecution. Thus even in times of inquisitorial fervor the ideas could circulate beneath the surface of orthodoxy, as the objects of scholarly interest or of artistic appropriation. For me the most startling early reception of Lucretius is in the art of Botticelli and the writing of Montaigne.

Interviewer: Do you feel a modern poet could generate the kind of cultural influence that Lucretius did with one poem?

SG: It seems unlikely, but who knows? The world is full of surprising shifts in unexpected directions and from unanticipated causes: that is the nature of what Lucretius called the swerve.

Interviewer: The Swerve recounts an important moment in cultural preservation in which a scholar reaches for a manuscript. In the digital age, how are we to preserve our cultural inheritance?

SG: We have in effect exchanged long-term durability — the legibility of the parchment after centuries — for instant access. The access is a magnificent achievement; I marvel at it every day. But it comes at a high risk, and I do not know what we would do if, as it were, the plug were ever pulled. The Swerve is a story of recovery, but most of the cultural inheritance of that ancient world was in fact lost, and Lucretius himself was hanging by a thread.

Interviewer: You are a Shakespeare expert. Has the writing of this book influenced your view of Shakespeare's work?

SG: I think that Shakespeare's sensibility was fundamentally secular and believe that there are traces of the revival of Epicureanism in his work. But I am more struck by the parallel between the cultural significance of Lucretius and the cultural significance of Shakespeare. Here are two artists who changed the world. To put it a different way: can you imagine what it might have been like to lose Shakespeare for a thousand years and then, all at once, to recover his work?