Book on the Secrets of Alchemy of Constantine of Pisa, relied heavily on the fourth book of the Meteorologica, which included Aristotle’s theory of metals.7 Likewise Paul of Taranto, a Franciscan lector, authored early alchemical treatises that lean on Aristotle and his commenters.8 Paul (under his own name as well as that of “Geber”) also transmitted a theory on the generation of metals that linked them to the heavens. Contemporary astrological theory held that terrestrial objects were governed by heavenly bodies for which they had an affinity. For metals, the sun was related to gold, the moon to silver, and, predictably, Mercury to mercury. The Book of the Secrets of Alchemy includes this idea, but also holds that the celestial bodies were the origin of these metals.9 The idea was that heavenly rays penetrated the earth and congealed within it as metals, helping to explain the affinity between celestial and terrestrial.10 The celestial-terrestrial relationship would prove fertile ground for future alchemical speculation.
Roger Bacon and Inestimable Glory
In 1268, Bacon completed his Opus tertium (The Third Work), as part of a hastily written collection of texts that responded to a 1266 command of Pope Clement IV. The Opus tertium was a recension of the Opus minus (The Lesser Work), itself a recension of the Opus maius, a hastily written but voluminous tome he had sent to the pope probably in 1267. In this third work, Bacon writes that, for fear of alchemical secrets falling into the wrong hands, he has consigned some of the most vital secrets to his aide, John, from whom the pope can have this knowledge transcribed.11 He also says that in addition to what John can convey verbally, there are two other sections Bacon had written obscurely, one in code (enigmatas) and the other in philosophical language so that a reader would assume Bacon was discussing medicine or natural philosophy rather than alchemy.12
We should not take this to mean that Bacon is short on detail or secretly skeptical about alchemy. In the short period since he had written the Opus maius after promising the pope he had already completed it, Bacon seemed more sanguine about alchemy, a notion bolstered by his later writings.13 In fact, he had taken a cautionary tone regarding alchemy in his Opus maius. Speaking about the medicinal use of alchemical gold, a substance Constantine of Pisa believed might be capable of halting the spread of leprosy, Bacon opined that the gold produced by alchemists was not of a particularly high grade.14 Interestingly, however, he said the same thing about gold found in nature, allowing that certain scientific arts might allow for the production of an even higher grade of gold. No doubt one of the reasons Bacon felt the need to create the Opus minus and Opus tertium was his evolving notion of alchemy.
In the Opus maius, Bacon had yet to align the practice of alchemy with what he called scientia experimentalis, troublingly translated with the cognate experimental science. By the time he wrote the Opus tertium, however, Bacon had divided the practice of alchemy into what he called “speculative” and “operative” alchemy. Operative alchemy was practiced, but not (fully) theorized. Operative alchemists could be skilled practitioners, but they did not comprehend the primary goal (finem principalem) of alchemy.15 Speculative alchemists, of whom Bacon said there were but a handful, understood the uses to which alchemy could be put in regard both to inanimate matter, such as metals, dyes, and tinctures, but also to animate or living matter. Living matter, chiefly the human body, was the province of the speculative alchemist.16
Living matter corresponded to inanimate matter, but was more complex.17 Like other Aristotelians, Bacon understood the four basic elements as arising from the four primary qualities (cold, dry, hot, wet).18 From the elements come the simple humors, which correspond to the standard humoral model: phlegm, choler, melancholy, and blood. The simple humors have “conjoined natures” (conjungentes naturae) of the elements, that is, one element and its particular qualities (cold and dry, hot and dry, cold and wet, and cold and dry) dominate.19 These humors, however, are not the same as bodily humors. The bodily humors are themselves a combination of simple humors. Each is dominated by one of the simple humors. So, bodily phlegm is a secondary humor, made up of four primary or simple humors, with primary phlegm dominant. Bacon’s system, then, makes animate bodies more complex expressions of humoral interaction than those found in inanimate bodies.20 To make true blood, one had to purify bodily blood of the other simple humors mixed within it.
Given the relationship of humors to elements, Bacon considers alchemy one of the essential fields of knowledge for understanding living things, so long as it is married to scientia experimentalis.21 Jeremiah Hackett has distilled Bacon’s description of experimental science into three “prerogatives.”22 The first is the rigorous application of logic to observation and experience. The term “experience” is, in fact, closer to the meaning of experimenta than is the cognate “experiment.” Bacon argues that observation of phenomena can teach us new truths and even refute truths supplied by reason alone, as long as we apply our critical faculties to what is being observed. The second aspect of experimental science is the creation and manufacture of tools, weapons, and medicines. For instance, in addition to the elixir, Bacon proposes using experimental science to create giant mirrors capable of incinerating enemies at a great distance.23 Finally, Bacon believes that experimental science can supply a reliable source of divination for knowing things of the past, present, and future. This generally relates to the observation of astrological phenomena, but his writings on the elixir suggest that human beings may be able to gain such knowledge instantly.24
This is a good indicator that Bacon meant something rather different from experimental science by scientia experimentalis. In the Opus tertium he even calls certain branches of scientia experimentalis “magical (magicus).”25 In one sense, this is atypical of Bacon’s work, since he generally uses the term “magic” to describe deceits.26 On the other hand, the breadth of sciences Bacon recommends includes a number of practices that are defined, certainly today and often in medieval culture, as magical. Divination and the utterance of “words of power” are just as much a part of Bacon’s program as geometry. Thus, Bacon’s use of the term “magic” tends to have ethical and religious overtones. The medieval approach to magic was to define it in opposition to religion. Modernity retains the tendency to define magic as part of a binary, but the modern definition tends to contrast it with science.27 The problem here is that, well into the early modern period, the magic-science binary was not distinct, given the conviction that, as Michael Bailey has put it, “the natural world was conceived as a direct manifestation of the supernatural order.”28
Bacon is quite aware of the problem of terminology. One of the reasons he advocates so strongly for scientia experimentalis is that too many of its practices have been discarded as magical or sorcerous, when they should belong to the natural philosopher.29 Bacon argues that the application of scientia experimentalis, especially critical observation, can help sort out what is magical and what is not.30 Bacon uses the example of a magnet to prove this point. People are easily fooled, he argues, when a fraudulent magician uses a magnet to attract iron. By uttering incantations or scrawling sigils on the ground, the magician makes people think that these activities move the iron, when it is in fact the natural property of the magnet.31 On the other hand, Bacon does not reject magical words or symbols wholesale, griping at one point that women and demons have “abused characters and incantations written by the wise.”32 Therefore, scientia experimentalis enfolded a wide variety of practices, linking them through a particular methodology.
One linkage in particular bears special mention, namely, the relationship between astrology/astronomy and medicinal or speculative alchemy. As noted in the prior section, the connection between celestial bodies and terrestrial bodies (of any kind) was understood to be quite strong. Bacon himself was a fierce defender of the merits of astrology and reinforced the link between celestial bodies and human physiology.33 The effect of celestial motion on the human changed from moment to moment, and intersected with a person’s humoral make-up,
