the topic of natal astrology, while Tractatus de imbribus et aeris mutationibusdeals with
astrometeorology.
Like most ancient and medieval texts on astrology, Bonatti’s book has some-
thing to say about character analysis, but little about psychology. The emphasis is on
the objective behavior of the native and others in the native’s life, with an eye toward
predicting the external events (the accidents of the native) rather than the subjective
response to them or to their alleged significance. The Liber astronomicusis concrete in
its interpretations. The author is direct and does not mince words. He is usually forth-
coming in his appraisal of his sources. He regards Abu ̄ Ma‘shar as a prince of astrology
and usually accepts the Persian astrologer’s opinion on most subjects. Bonatti general-
ly arranges his discussion of astrological procedures by first presenting the reader with
a detailed description of the astrological method and then bringing forward special
cases and the opinions of the ancients. The fate of Bonatti’s Liber astronomicusis the
fate of western astrology.
In the Renaissance, due in part to political and military realities following the
fall of Constantinople to the Muslim Turks, and to Turkish occupation of the Balkans,
there was considerable fear in western Europe that Christendom would fall under the
Muslim Turkish control. An intense anti-Islamic response ensued in which all things
Turkish, Arabic, and Islamic were repudiated. The intelligentsia, among whom the
astrologers were to be counted, turned towards scientism, in particular to Copernicus’s
heliocentricity, abandoning the geocentric astronomy of Ptolemy and Aristotle that
had become by this time embedded in the Catholic worldview. Bonatti’s astrology,
which had entered Western Europe as part of the “New Science” in the twelfth centu-
ry, was now regarded as typical of the old Catholic cosmology by contemporary critics
who sought a new New Science 300 years after the last “renaissance.”
As a result of the Turkish threat, the Reformation, the Thirty Years’ War, and
the beginnings of the Scientific Revolution of the seventeenth century, western Euro-
pean intellectuals turned increasingly toward Greek science, secularism, scientism,
and rationalism. Greek science, astrology, and mathematics were regarded as superior
to their Arabic counterparts. As western philology demonstrated the adulteration of
pristine Greek texts of Ptolemy’s Tetrabiblos,for instance, the Arabic astrology was
increasingly regarded as corrupt.
Repudiated by the intellectually superior and educated, bona fide astrology à la
Bonatti’s Liber astronomicuswas ignored on the continent, as was the entire subject of
astrology until the “Occult Revival” of the nineteenth century. Perhaps because it was
used for propagandistic purposes during the English Civil War (1642–1646) and dur-
ing the Commonwealth (1649–1660), astrology was preserved in England. Neverthe-
less, it was not the “papist” medieval astrology that survived, but a “reformed” and
simplified astrology intended to make the science of the stars popular and, thus, politi-
cally useful. Later, in the eighteenth century, the almanacs made astrology accessible
as entertainment to the partially educated.
Bonatti’s Liber astronomicusis an important resource for the practicing
astrologer. From the point of view of the history of science, it may be viewed by some
as an example of superstitious protoscience or pseudoscience. From the theological
THEASTROLOGYBOOK [93]
Bonatti, Guido