The Swerve: How the Renaissance Began by Stephen Greenblatt – review

This concise, learned and fluently written book tells a remarkable story. It may not quite tell us "how the Renaissance began", as the subtitle rather rashly promises, but the episode it describes is certainly resonant. Highly skilled, close-focus readings of moments of great cultural significance are Stephen Greenblatt's speciality, whether in "new historicist" studies such as Marvellous Possessions, about the European encounter with the New World, or in his more populist biography Will in the World: How Shakespeare became Shakespeare.

The story begins at a monastery in central Germany – almost certainly the Benedictine abbey of Fulda. At its gates, in the first weeks of 1417, arrived an itinerant Florentine scholar by the name of Poggio Bracciolini. A slight, genial man in his mid-30s, he had served as a papal secretary but was currently unemployed owing to the deposition of Pope John XXIII. Today Poggio is best remembered for his vituperative controversy with Lorenzo Valla (a "war of wits" much savoured by Elizabethan comic writers such as Thomas Nashe) and for his salty joke collection, the Facetiae, whose frequent obscenities are rendered in flawless humanist Latin.

But while these later levities give us a feel of the man – droll, engagé, faintly disreputable – his more far-reaching contributions lay elsewhere. A brilliant Latinist and an ardent bibliophile, he was dedicated to recovering the literary and philosophical masterpieces of the classical world, which had been lost and scattered during the so-called dark ages. He was, as Greenblatt puts it, a "book-hunter", and his arrival at Fulda was not as a pilgrim but as an ingenious and tenacious literary detective in search of treasures within the abbey's rich library of manuscripts.

He had already made some important discoveries. A couple of years earlier, in Cluny, he had turned up a codex containing seven orations by Cicero, two of them previously unknown. These works were lost "through the fault of the times", he wrote on his own handwritten copy of the codex, until "by repeated search through the libraries of France and Germany, with the greatest diligence and care, Poggio the Florentine all alone brought them out of the sordid squalor in which they were hidden and back into the light." This dramatic metaphor of imprisonment and rescue is even stronger in Poggio's account of discovering a manuscript of Quintilian's Institutes, "filthy with mould and dust", lying neglected in the monastic library of St Gall, as if in "a sort of foul and gloomy dungeon… where not even men convicted of a capital offence would have been stuck away". Here, Greenblatt notes, Poggio's language echoes certain comments he had made a few months earlier, after witnessing the trial and subsequent burning of the Hussite heretic Jerome of Prague.

But it was in Germany in 1417, very probably at Fulda, that he found his biggest prize – a ninth-century manuscript copy containing the entire 7,400-line text of De Rerum Natura ("On the Nature of Things") by Lucretius. This extraordinary philosophical epic poem, composed in Rome around the middle of the first century BC, was at this point known only by name. It was a missing celebrity of the kind Renaissance book-hunters dreamed of finding. Distant hints of its initial impact could be heard in a letter of Cicero's of 54BC, which spoke of its "brilliant genius"; in Ovid's commendation of "the sublime Lucretius"; and in Virgil's lines from the Georgics, "Blessed is he who has succeeded in finding out the causes of things, and has trampled underfoot all fears", the latter phrase echoing a line of Lucretius's – "religion is trampled underfoot" – which would send a shiver through 15th-century Europe.

Of the poet himself, Titus Lucretius Carus (c 99-55BC), almost nothing was known, which remains more or less true today. A brief biographical sketch by St Jerome, written sometime around 400AD, says he killed himself at the age of 44, "after a love-philtre had turned him mad", and that his poetry was written "in the intervals of his insanity". This is undoubtedly, as Greenblatt cautions, a polemical spin by a church father with "an interest in telling cautionary tales about pagan philosophers".

The poem is powerfully ranged against spiritual and supernatural beliefs. It posits a solely material world in which everything is composed of minute particles, the "seeds of the things" – the world of "atoms" previously proposed by Democritus, though Lucretius does not himself use that word. Among the dangerous ideas elaborated from this (as summarised by Greenblatt) are that the universe was not created by divine power; that the soul dies with the body; that there is no afterlife; that all organised religions are superstitious delusions; and that the highest goal of human life is the enhancement of physical happiness in the here and now. In short, it offered a highly charged, poetic exposition of Epicureanism, that philosophy of upbeat fatalism which the church had feared and condemned ever since.

This was the incendiary, anti-religious manifesto, ironically preserved for posterity in a monastery library, which Poggio Bracciolini released anew into the world. Greenblatt pursues with gusto the ramifications of the "Lucretian challenge" in the Renaissance, from the symbolism of Botticelli's La Primavera to the radical cosmology of Giordano Bruno. His title, The Swerve, is itself Lucretian, being a translation of the Latin clinamen, used by Lucretius to describe the unpredictable movements by which particles collide and take on new forms. The rediscovery of Lucretius, it is suggested, was a kind of "swerve" which helped to create the new cultural forms of the Renaissance.

The actual Lucretian codex found by Poggio has since disappeared, as has the direct copy of it done for him by a German scribe, but the beautiful transcript made by his friend Niccolò de' Niccoli survives today; its concluding folio is shown here among the colour plates, a ravishing archival pin-up.

This is a superb essay on the transmission of ideas, but it is also a kind of eulogy to the power and tenacity of manuscripts – a chain of remembrance, a drama of survival. It celebrates the scribal skills of men such as Poggio and Niccolò, whose exquisite, flowing, italic script was the model for early printing fonts designed by Aldus Manutius and others. It also gives insights into the work of those unnamed medieval monks who toiled in the monastic scriptoria, in a spirit of penance as much as of craftmanship, and whose discreetly inserted grumbles – "Thin ink, bad parchment, difficult text" – sometimes remain on the pages they produced.

In 1987, a team headed by a Neapolitan curator and a Norwegian papyrologist succeeded in deciphering and identifying 16 scraps of charred papyrus found at Herculaneum. They proved to be fragments of an early copy of De Rerum Natura – possibly a copy made during the author's lifetime, certainly one in circulation before August AD79, when Herculaneum was engulfed in the eruption of Vesuvius. Without the copyists and book-hunters like Poggio Bracciolini, these tiny textual remnants might have been all that was left of this visionary poem.

Charles Nicholl's Traces Remain: Essays and Explorations will be published by Allen Lane in December