optics required the mathematics of lines, figures, and angles. Grosseteste was, thus, one
of the first to link mathematics directly to the study of natural phenomena beyond the
movements of the heavenly bodies.
Grosseteste wrote Commentaries on the Physics and the Posterior Analytics of
Aristotle and produced some original treaties on optics. Perhaps no one, however, better
expresses the impact of the full corpus of Aristotle’s works (and their Arabic
commentaries) made available by the 12th- and 13th-century translations than Albert the
Great. His voluminous writings include detailed commentaries on Aristotle’s physical
and biological treatises, to which he added extensive examples of his own observations of
flora and fauna gained on his travels on foot in Germany, France, and Italy. What
characterized Albert’s approach to science and set him apart from many of his
contemporaries was his continuous insistence on his own observations and on the need to
return to what in Latin is experimentum. The term “experiment” cannot be understood in
the modern sense. More often than not, the term indicates a careful, scrutinizing process
of observing, describing, and classifying. At the same time, natural magic was considered
a branch of science: the science that dealt with “occult virtues” (or hidden powers) within
nature. God acts through natural causes in the case of natural phenomena, says Albert;
and while we would not presume to investigate the causes of the divine will, we are free
to investigate—in detail and specifically—the natural causes that are instruments of the
divine will. It is in the spirit of what Albert reads in Aristotle (and in pseudo-Aristotelian
texts) that he seeks concrete, specific, detailed, accurate knowledge of everything in
nature. There are many powers of stones and plants that are learned by experience, and
magicians, as well as natural philosophers, investigating these powers, work wonders
with them.
Albert’s reputation for magic was probably based on two things: 1) there are many
references to magic scattered throughout Albert’s writings, many of them expressing
approval, and some include explicit treatments of the special case of magic, astrology;
and 2) the prodigious accumulation of factual (and reportedly factual) knowledge of the
natural world, including the medicinal powers of herbs, the folklore about the powers of
stones and minerals together with theories of the structure of natural substances and the
organization of the universe: all contributed to a Faustian characterization of this one man
of the 13th century to be called “Great.”
The association of science and the magical arts is evidenced in several ways. The
Libellus de alchimia, for example, lists several (“scientific”?) precepts for the alchemist
to follow:
1) the alchemist/scientist should work silently and secretly; if many know
what he is doing, the secret will not be kept and when it is divulged, it will
be repeated with error; 2) the scientist should have a laboratory—a special
house away from the sight of others in which to carry out his procedures;
3) the scientist must observe the time and the seasons; 4) the scientist
must be sedulous, persevering, untiring—a constant worker; if he begins
and does not persevere, he will lose both materials and time; 5) in all
procedures, the scientist must have and follow a protocol; 6) all vessels
should be made of glass; 7) the scientist should stay away from
administrators; if you are committed to your work, they will bother youMedieval france: an encyclopedia 1632