Roger Bacon: the Opus maius, the Brazen Head and the Voynich

In 1267 an English Franciscan friar sent Pope Clement IV a great treatise in seven parts, accompanied by two complementary works. The author was Roger Bacon, born between about 1214 and 1220 and who died around 1292, and the treatise was the Opus maius, a programme for reforming learning that gave a central place to languages, mathematics, optics and what he called scientia experimentalis.

The Opus maius and Experimental Science

Bacon had studied and taught at Oxford and Paris before entering the Franciscan order around 1257. The pope, who had known him before his election, had asked him to send his writings. The result, besides the Opus maius, was the Opus minus and the Opus tertium, written in haste and partly overlapping, which reveal an ambitious thinker, often scornful of the scholars of his day.

In the Opus maius Bacon argues that knowledge of nature must be tested by experience and grounded in mathematics. He devotes famous pages to optics, refraction and the rainbow, and calls for the direct study of Greek, Hebrew and Arabic. For him science served faith and the Church rather than opposing them: a point often forgotten by his modern admirers.

The Letter on the Secrets of Art and Nature

Bacon's name is also linked to the Epistola de secretis operibus artis et naturae, et de nullitate magiae, a letter describing the wonders that human art can achieve without resorting to magic. It imagines ships without rowers, carts moving without animals and flying machines. The authorship of the text, at least in the form in which it has come down to us, is debated, and some parts appear to be later additions.

The message of the Epistola is clear: many things the common people believe to be magical are in fact natural or artificial effects, and the magic of enchanters is empty. Paradoxically, the very text that denied magic helped to turn its supposed author into a magician, because it spoke of secrets, deceptive mirrors and substances capable of marvels, in deliberately allusive language.

The Brazen Head and the Voynich Manuscript

In the sixteenth and seventeenth centuries the legend of Friar Bacon was enriched with fantastic episodes. The best known is that of the talking brazen head he supposedly built to protect England with a wall of brass, made famous by Robert Greene's comedy Friar Bacon and Friar Bungay, staged around 1589, and by prose tales popular with readers of the time.

In the twentieth century his name was associated with the Voynich manuscript, the illustrated codex in an unknown script bought by the bookseller Wilfrid Voynich in 1912. Voynich believed the author was Bacon, and some attempts at decipherment started from this idea. Radiocarbon analyses carried out in 2009 dated the vellum to the first half of the fifteenth century, effectively ruling out the attribution.

The historical Bacon and the legendary one share only their curiosity. The first was a learned friar who believed in the unity of wisdom and faith and in the power of mathematics; the second, a magician invented by later readers. It is no accident that John Dee, in the sixteenth century, devotedly collected his manuscripts, seeing in him a model natural philosopher and a forerunner.