From Magus: The Art of Magic from Faustus to Agrippa, which will be published next month by Harvard University Press.

In the sixteenth century, opinions of the famed Doctor Faustus varied. Many considered him a charlatan, but some witnesses spoke in more than one key about his magic. One critic, the Lutheran reformer Philip Melanchthon, glossed his critique of Faustus with an almost admiring remark about the magician’s supernatural patron: “The devil is a marvelous artisan. For by a certain art he can achieve things which are natural, and which we do not know. For he can do more than man.” Here Melanchthon describes the devil’s art as that of a supremely inventive craftsman, a “mirabilis artifex” who could draw out the “occult virtues” of nature as no human could.

Most of Faustus’s actual practices went unrecorded. But one episode connects him to a world of marvelous craft. He lectured publicly on Homer at the University of Erfurt, where he briefly held an academic post. He described the heroes of Homer’s epics—King Priam, Hector, Ajax, Ulysses, and Agamemnon—in vivid detail, “each as they had appeared.” Excited students demanded more wonders. Faustus agreed to grant their desire in the next lecture hour. When a swarm of eager listeners showed up, more than before, he brought the Homeric characters in “one after another.” Each hero “looked at them and shook his head as if he were still in action on the field before Troy.” Finally, he introduced Polyphemus, the red-haired, bearded, ferocious cyclops—who entered with a man’s legs dangling from his mouth, frightened the students, and refused at first to leave but instead “hammered on the floor with his great iron spear.”

Faustus knew how to stage a show. In this case, he staged a particular kind of demonstration, one that others had been developing for more than a century. A fifteenth-century natural philosopher and inventor, the Padua-educated Giovanni Fontana explained how to project images. A vivid, partly inaccurate illustration represents a learned man, dressed in the robes that reveal his status, holding a transparent lamp. The light of a candle transforms a tiny image of a devil armed with a sphere, inside the lamp, into a vast, frightening projection. Faustus used his own expert knowledge of optics, light, and shadow to project large-scale images of Greeks and Trojans on a sheet, which a
confederate shook so that the figures
seemed to move.

Almost all engineers of the time connected their practice, implicitly or explicitly, with the powers of magic. They accomplished this in different ways. Sometimes they simply claimed to practice both arts. The German military engineer Konrad Kyeser, for example, described and illustrated not only wheeled carts but also magical practices, which he portrayed with equal enthusiasm. Along with the ancient planetary gods, an unclassical spirit named Salathiel appeared in Kyeser’s work. According to Johannes Hartlieb, writing half a century later, the masters of the art of hydromancy—or divination by water—believed that God had not created water because the Book of Genesis described the spirit of God as hovering over the waters. “They hold,” he added, “that there are special spirits that dwell in the water. These, they believe, can reveal all things, future and past. And they call the greatest and most powerful of these spirits Salathiel.”

Texts of the period often cast magic and engineering in strikingly similar keys. One of the Italian polymath Taccola’s curious inventions involved a dog tied by a long line to a bell at the top of a tower. The dog’s desperate efforts to reach food and water left just beyond his range would make the bell ring, creating the illusion that a deserted fort was still occupied. Taccola suggested that this illusion would enable a lone soldier to leave the fort, obtain food and water, and return to it before the enemy realized he was gone.

Both magicians and engineers claimed that they could create powerful illusions—and saw the task as a significant part of their art. The theatrical style that magic and engineering assumed in this period would persist for centuries.

When Thomas Cromwell dissolved the English monasteries, he and his allies seized on every piece of evidence they could to portray the monks as charlatans who had long exploited the simple piety of the English. One of the most prominent was the Rood of Grace, a crucifix from Boxley Abbey that featured a likeness of Jesus that could move its eyes, shed tears, and turn its head. When the crucifix was removed from its position on the wall, Geoffrey Chamber found “olde roton stykkes in the backe of the same, that dyd cause the eyes of the same to move and stere in the hede thereof lyke unto a lyvelye thing; and also the nether lippe in lyke wise to move as thoughe itt shulde speke.” The news of its exposure circulated rapidly among Protestants of different stripes, who witnessed the downfall of Dagon with enthusiasm.

But it is not certain what the monks of Boxley claimed or thought about the Rood. Did a few of them know and keep its secret? Did they expect their visitors to suspend disbelief while they marveled at the figure’s movements, while knowing that they were mechanical? The antiquarian William Lambarde, who examined Kent’s antiquities in granular detail, recorded a tradition that the Rood had been made by a clever English craftsman while he was in captivity in France, “so that now it needed not Prometheus fire, to make it a lively man, but onely the helpe of the covetous Priestes of Bell, or the ayde of some craftie College of
Monkes, to deifie and make it passe for
a very God.”

Across Europe, in Naples decades later, the Dominican friar Tommaso Campanella reviewed the varieties of magic. Artificial magic, he explained, “either uses things made by art or uses things made by nature in an artful way in order to produce unusual effects, whose causes are unknown.” Any device that inspired wonder and whose workings weren’t understood counted as an “artificial miracle.” This “clock that indicates the hours is a miracle, at this time, to the Chinese, for both reasons, but not to the Italians, who are used to them and understand their mechanism. Custom has made them less miraculous even for our peasants, who do not understand how they work.” The first cannon in Italy, Campanella argued, possessed magical effects, though these traits had been lost over time; so had the first guns used by the Spanish in the Americas, whose inhabitants took them for gods.

Campanella explained that magic of this sort could take two forms: “deceptive” or “real.” “Real artificial magic,” in his terms,

produces real effects, as when Archytas made a wooden dove that flew, and recently at Nuremberg, if we may credit Botero, they made an eagle and a fly of this kind. Archimedes used mirrors in combination to burn a fleet that was far away. Daedalus made statues move with weights or quicksilver.

Only after Campanella had described this sort of magic did he move on to those that transformed elements or organisms, or that used talismans and characters to produce their effects. Mathematical magic was a solid foundation on which much of the edifice of learned magic now rested.

From a discipline that once challenged the magi and their art, mathematics had become a central part of magic, and it would continue to have that status even as machines became the principal sources of wonder for erudite natural philosophers.