Monica Azzolini. The Duke and the Stars. Astrology and Politics in Renaissance Milan. Cambridge: Harvard University Press, 2013. xiii + 370pp, b&w figures, general index.

Ugo Baldini and Leen Spruit, eds. Catholic Church and Modern Science: Documents from the Archives of the Roman Congregations of the Holy Office and the Index - 16th Century Documents 4 volumes. Rome: Libreria Editrice Vaticana, 2009. xli + 3380pp., b&w ill., name index. Fontes Archivi Sancti Officii Romani, series Archivi Congregationis pro Doctrina Fidei, 5.

Fabrizio Bònoli, Giuseppe Bezza, Salvo de Meis, and Cinzia Colarita. I prognostici di Domenico Maria Novara. Florence: Olschki, 2012. vii + 317pp., b&w figures, name index.

Mary Quinlan-McGrath. Influences. Art, Optics, and Astrology in the Italian Renaissance. Chicago: Chicago University Press, 2013. xi + 284pp., b&w ill., color plates, general index.

The Roman Inquisition against Heretical Depravity, also known as the Holy Office (HO), established in 1542, and the Congregation of the Index of Prohibited Books (CI), announced officially in 1572, undertook to protect Italy from ideas and practices that menaced the authority of the Roman Catholic Church in this world and the salvation of its members in the next. This grandiose public-health program required trained and dedicated thought police to receive and evaluate alarms from the public and, when business was bad, to seek out sources of infection themselves. The resultant records of accusations, investigations, trials, condemnations, expurgations, and exceptions, if extant in its entirety, would go far to fill the nave of St. Peter’s. Time has so withered the records, however, that it is now practical to consider a printed edition of all the documents pertaining more or less to natural knowledge created by the HO and the CI from their establishment in the sixteenth century to the suppression of papal government by Napoleon in 1808.

1. The Police Records

The inquisitorial records among which Ugo Baldini and his collaborators have selected documents related to “science” represent only a fraction of the paper created by the HO. Many records disappeared in the destruction of its offices by a Roman mob in 1559. Others it burnt itself to prevent their capture by invaders. The greatest loss occurred during the removal of the HO’s papers to Paris by Napoleon and their subsequent return to Rome. The papal agent charged with repatriation sold off many tons as waste paper to help pay the transportation costs of the rest. Additional losses occurred during the Italian political crises of the nineteenth century. The seriously depleted archive of the HO and the largely intact records of the CI now reside in the Archive of the Congregation for the Doctrine of the Faith. Although the CI’s papers suffered far fewer depredations than the HO’s, they amount in bulk to only a twelfth of the 610 running meters of material from which Baldini and his collaborators have chosen their documents.

The selection criteria though vague are judicious. Baldini applied neither the meaning of scientia at the time the documents were produced nor that of “science” in our own time, but a combination and mutual limitation of both. The result is the inclusion of all science in the modern sense, pure and mixed mathematics, general physics, psychology, natural theology, biblical exegesis, chronology, astrology, natural magic, and divination. Here an important distinction in the jurisdictions of the Holy Office and the Congregation of the Index is useful. Although both could prohibit books, the HO attended to people, the CI to written material. Consequently, Catholic Church and modern science presents most of its documents as files devoted to individuals. The files vary in size from an item or two to the 79 documents, covering 440 pages, dealing with Girolamo Cardano. In the laborious years of transcribing and checking the documents, Baldini had the collaboration of Leen Spruit. But the concept and design of the project and the necessary negotiations with Cardinal Joseph Ratzinger (Pope Benedict XVI), who presided over the Archive of the Congregation for the Doctrine of the Faith when the project began, were the work of Baldini.

The four volumes of Baldini and Spruit contain much more than transcriptions and annotations of documents. They also offer accounts of the workings of the HO and the CI, and the background and content of the sixteenth-century Indexes; extensive summaries of the general inquisitorial documents pertinent to alchemy, astrology, magic, medicine, and natural philosophy; résumés of the files of 86 individuals in whose science the Inquisition took an interest; and requests for licenses for keeping and reading prohibited or unexpurgated material. From these requests Baldini and Spruit have determined the relative popularity of banned authors and found Cardano to have been the favorite. Their fourth volume contains an imposing scholarly apparatus of biographical sketches and bibliographies. An index of names allows access to quantities of information to users patient enough to look through dozens and even hundreds of undifferentiated references. The surveys, summaries, and apparatus are in serviceable English, occasionally made challenging by such Italianisms as “contrast” for “oppose” and “relevant” for “important.” The documents are in Italian or Latin.

Reading Baldini and Spruit’s commentaries and leafing through the documents can inspire sympathy for the conscientious censor. He faced an impossible task. Not only did his assignment require that he hunt out all ideas inimical to the faith and find some way to block them, he operated on a constantly expanding field with goal posts that jumped with almost every change of pope. In more than one case, a pope suppressed his predecessor’s index before it could be promulgated, whence the odd category of prohibited indexes of prohibited books. Paul IV’s Index of 1559, issued by the HO, consulted efficiency as well as safety by prohibiting all books by Protestant authors on all subjects whatsoever. Unfortunately, some of these books contained information important for the faithful to know. In such cases, competent censors might remove the dangerous parts and pass the innocuous remainder. The Tridentine Index of 1564 made provision for this sort of expurgation. Thereafter, the system lurched from permissiveness to severity and burdened its personnel with endless reading, purgation, and enforcement. As will appear, shifting policy toward astrology left readers and censors alike uncertain whether books about it were allowed or not.

Among the most interesting files published by Baldini and Spruit is that of Girolamo Borro (or Borri), Galileo’s professor of philosophy at the University of Pisa. Borro suffered the hospitality of the Holy Office in four separate affairs. Most of the inquisitorial documents referring to them report decisions of the cardinals of the HO in response to appeals or explanations by the accused. The decisions in Borro’s cases ran from no action, which left him incarcerated, through release on bail. When bailed and sometimes when not, Borro had to submit to detention in habitats that ranged from a private house to all of Tuscany and the Papal States. Nothing was too small for the inquisitors’ examination. One document requires bail against misuse of the knife, glass, and other household utensils that the HO lent Borro during one of his stays in its full-service accommodations, and against breaking, or causing to be broken, the walls or entrance of his cell (p. 846).

Why did the Inquisition take so keen an interest in Borro? Unfortunately, the documents seldom even hint at the charge. Most of their content is formulaic: on this date these cardinals met at this place to discuss these cases of which one concerned Girolamo Borro, whose petition in the case under consideration, having been read and understood, the cardinals decided that. To supply the motivations for the prosecution of Borro, Baldini and Spruit turn to other inquisitorial papers, particularly of the Pisan Inquisitor. From them we learn that Borro suffered because of accusations that he taught the Aristotelian doctrine of the mortality of the soul; that one of his accusers was his own brother; and that, in the last case against him, he and other professors from Pisa and their students had to answer charges that they customarily read banned books and discussed harmful ideas. The archival evidence concerning the case includes letters from professors begging the head of the Holy Office to grant bail to their sons, one of whom, who was only 16, had been in jail for eight months.

The dire treatment of the errant Pisan academics, which descended to torture of one of the professors, occurred halfway through Galileo’s student years at Pisa. He could not have been ignorant of the episode as even Borro, who knew the ways of the Holy Office, was shaken by the experience. Perhaps Galileo narrowly missed being implicated himself. The chances of being compromised by a zealous or jealous colleague were enhanced not only by uncertainties in the rules, but also by competition among overlapping inquisitorial jurisdictions. The Pisan academics obtained licenses to read books from the Inquisitor of Florence when refused by his colleague in Pisa, but nonetheless ended in prison in Rome. Changes in staff and policy made it difficult to secure fireproof protection. The episode of the Pisan academics very probably fed the caution with which Galileo treated the Copernican system before his telescopic discoveries turned him into its apostle.

2. Varieties of Astrological Practice

Among the products of astrologers to which the Holy Office and the Congregation of the Index had to attend, the most widely distributed were printed annual forecasts or prognostici. Some of these came from high and informed sources, since by contract many university professors of mathematics or astronomy had the obligation to issue them. The prognostici of Domenico Maria da Novara, professor of astronomy at the University of Bologna from 1484 until his death at fifty in 1504, have special interest because Copernicus studied, assisted, and lived with Novara during this period, from 1496 to 1500. Many historians have conjectured about connections between Novara’s teachings and Copernicus’ reform. The latest is Robert Westman, who proposes that Copernicus’ main concern, developed during his time with Novara, was to improve astrology by finding the true order and distance of the planets. With this information, so Westman’s argument goes, the relative strengths of the planetary influences could be calculated rationally and the mighty attack on astrology mounted in Giovannni Pico della Mirandola’s posthumous Disputatio adversus astrologiam divinatricem (1496) be refuted.1

No works by Novara seem to be extant apart from his prognostici from which his response to Pico can be inferred. However, a marked shift in the content of the preambles to the prognostici occurred after Pico’s intervention: whereas the earlier ones concern technical details, like a charge of inaccuracy against the Alfonsine Tables and, remarkably, the discovery of a spurious shift in the direction of the earth’s axis, the later ones are defensive. They concede that reason can block the action of the stars (though, to be sure, not easily) and answer such objections as the impossibility of accurate determination of planetary positions and the implausibility of assigning continuing human actions to fleeting heavenly conjunctions. Westman makes good use of the almanac of 1499 to suggest the nature of Novara’s defense of astrology. But there is little if anything in the almanacs to show that Novara worried about the dimensions of planetary orbits. His predictions required angles (aspects), angular velocities (duration of eclipses), and the accepted rules, both Greek and Arabic, for defining the strengths and competences of the planets and luminaries in their mundane and celestial environments, but not planetary distances.

I prognostici prints transcriptions of all of Novara’s almanacs known to Bònoli et al. Curiously they missed one in plain sight, the prognostico of 1499 discussed by Westman. Curiously also, Westman had failed to find the prognostico of 1489 when Bònoli et al. had already discovered it. Both the 1489 and the 1499 reside in the same library! Habent sua fata libelli! In all, Bònoli located 32 almanacs, 17 in Latin and 15 in Italian, representing 12 of the 20 years of Novara’s professorship. For each of the 12 years (1484, 1487, 1489–1490, 1496–1497, 1500–1504), I prognostici prints one version in each language if both are available. Bònoli and Cinzia Colarita made the transcriptions, to which several prefatory essays give easy access. Bònoli writes judiciously about Novara’s life and work; Giuseppe Bezza helpfully analyzes the astrological principles on which Novara based his interpretations; and Salvo De Meis painstakingly recalculates planetary, lunar, and solar positions wherever Novara provided enough information to make comparison with modern values and the Alfonsine tables possible. It appears that Novara deserved his reputation as an authoritative astrologer and accurate calculator.

As annual forecasts, Novara’s prognostici work with celestial configurations defined by criteria plausibly related to the current year. He chose usually to follow the Greek way, which took the circumstances of the planets and luminaries at the syzygy immediately preceding the vernal equinox as the clue to the year’s vicissitudes. (Ptolemy, Tetrabiblos 4.10 recommends the more laborious process of examining the syzygies preceding both the equinoxes and both the solstices.) Sometimes, however, Novara followed the Arabic way, which privileged the place of the last grand conjunction appropriately “progressed” to the current year. In either case, Novara followed the usual rules of astrological dominance to determine the lord or lords of the qualifying configuration, and to predict general happenings like wars, harvests, illnesses, and other widespread afflictions, and also the likely experiences of the natives of the several planets, the inhabitants of major Italian cities, kings in general, and the dreaded Turks. Novara expressed himself vaguely and cautiously enough to be not wrong most of the time.

Foreknowledge of general events allows the individual to take effective countermeasures, such as avoiding areas scheduled for war or famine, or refusing drinking water predicted to be contaminated. General indications did not suffice, however, for those who feared the stars and could afford to pay for bulletins about their danger and for professional help in deflecting it. The Sforza dukes of Milan in the later fifteenth century had good reason to worry about their safety and ample resources to engage the best astrologers. The resultant consultations left an extensive archival deposit, which Monica Azzolini has mined with evident delight. She begins by trying to define a corpus astrologicum, or standard curriculum, for aspiring astrologers, and succeeds in obtaining one with the same mix of Greek and Arabic techniques that appears in Novara’s forecasts. However, her main contribution is not a rehearsal of astrological apparatus, but accounts of the different tones, intensities, and purposes of the Sforzas’ astrological commitments.

One of these purposes was political. Dynastic marriages might be made in accordance with the harmony of horoscopes of the betrothed and dissolved if convenient by a fresh analysis of their progressed birth charts that revealed incompatibilities or medical problems. In this way the first Sforza duke, Francesco, who came to power in 1460, made and cancelled the marriage contract between his son Galeazzo Maria and a daughter of the Gonzaga rulers of Mantua in the hope of a more advantageous French connection. The Gonzaga worried in turn about Galeazzo’s sexual appetites; the Sforzas’ astrologers could reassure them that the boy’s lust, being a consequence of the place of Venus in his birth chart, was perfectly natural. When he became duke, Galeazzo Maria consulted astrologers frequently and collected predictions made by experts advising his enemies; for whether he believed in their forecasts or not, he knew that others did, and might act on the news that a certain ruler would soon die. He therefore strove to keep his name from the almanacs and threatened astrological warfare against the Este of Ferrara for allowing their astrologers to spread rumors of his impending death.

Galeazzo Maria’s heir, Gian Galeazzo, was a sickly boy of eight when his father fell to assassins in 1476. The evil uncle Ludovico il Moro, acting as guardian, treated Gian Galeazzo with the utmost consideration by immuring him in a castle under the care of the best doctors. The doctors administered to the boy with strict regard to the rules of astrology. Their frequent correspondence with Ludovico, who believed in its every jot and tittle, reveals the practice of astrological medicine in minute detail. The adverse influences in Gian Galeazzo’s horoscope, and also his illness, made his marriage to Isabella of Aragon, a granddaughter of the King of Naples, difficult to consummate. Seeking to break the celestial inhibition, the King sent two women appropriately experienced to instruct the young couple. Although they failed, Gian Galeazzo eventually managed the trick his father performed so well and created a daughter who had a colorful career. But he never recovered from his ailments. He died at the age of 26, a martyr to the medicines required by his horoscope, or, as some said, to the poison administered by his keepers on the instructions of his uncle.

Ludovico Sforza would not start on a journey, appoint an official, fight a battle, or bed his wife without the advice, which he followed almost slavishly, of his chief astrologer, Ambrogio Varesi da Rosate. Ludovico’s demand for forecasts about bizarre situations beyond the empirical basis of astrology, which earned the scorn of moderate astrologers like Cardano, no doubt gave Varesi many a headache; but he was prompt with optimistic advice about big political decisions like alliances between Milan and Charles VIII of France and the Holy Roman Emperor Maximilian I. The emperor laughed at Varesi’s rosy predictions and at Ludovico’s belief that he could contain Charles. Although Varesi had a number of big hits to his credit—he predicted the death of Innocent VIII to within two weeks—his forecasts of military support from Maximilian and of victory over the French were wide of the mark. In 1499 he and his lord, having received the advice of independent astrologers that they could not hold out, fled Milan. Ludovico took up with a new astrologer and no doubt followed professional advice when trying to regain his duchy in 1500. He misread the stars and spent the rest of his life in a donjon in France.

The subjects of astrological inquiry so far considered—war, famine, disease, political intrigue—might suggest that the science was more dismal than economics. No doubt it was safer to predict disasters than delights. But some sunny astrologers developed an optimistic practice by designing attractive talismans by which to strengthen the beneficent influences in a birth chart. These talismans incorporated materials adapted to receive, retain, and reradiate celestial power. More speculatively and dangerously, wealthy clients could surround themselves with correctly wrought pictures and images depicting the characters or personae of the planets and zodiacal signs whose good qualities they desired to trap. The authority in this business, the Neoplatonist philosopher Marsilio Ficino of Florence, recommended sleeping in a purpose-built chamber richly decorated with figures and colors and, when awake, remaining there to meditate about Jupiter and other good things.

Mary Quinlan-McGrath develops Ficino’s ideas in detail and extends them to explain the artistic programs of several celebrated ceilings. Of these the most representative and best known is the vault painted by Baldassare Peruzzi around 1511 in the villa he designed for the very wealthy Roman banker Agostino Chigi. Nine decades ago Aby Warburg identified Peruzzi’s beautiful depictions of planetary deities and zodiacal creatures as a clever presentation of Chigi’s horoscope, and since then other art historians, including Quinlan-McGrath, who is an expert on the subject, have added importantly to the analysis.2 She now goes further by applying Ficino’s ideas to Peruzzi’s paintings more literally, perhaps, than either of them would have done. According to her, we are to appreciate the paintings not only for their beauty and cleverness, but also, and above all, for their talismanic properties. She believes that Chigi, Peruzzi, and their knowledgeable contemporaries took the paintings to be reservoirs of celestial influence, and that they would benefit or suffer from exposure to the re-radiation of this influence according to whether their horoscopes harmonized or conflicted with Chigi’s. By making the vault both beautiful and complicated, Peruzzi forced Chigi’s guests to examine it minutely. Their prolonged exposure to the paintings improved or damaged them in proportion to the agreement of their characters with his. The author is certain about it. “The patrons of the major horoscope ceilings must have seen their images in this way” (p. 200).

In support of this far-fetched theory, Quinlan-McGrath devotes most of her book to describing pieces of Neoplatonic natural philosophy and the related concept of the multiplication of species found in Roger Bacon and his followers. There are also bits from the Christianized Aristotelianism of Saint Albert and Saint Thomas, who would be surprised at Quinlan-McGrath’s renditions of the concepts of form and matter basic to their philosophy. “Aristotelians did not believe that the heavens had materiality” (p. 128). Quinlan-McGrath is given to bold assertions. Some of them, like the one just quoted, are breathtaking (“the red light of Mars […][was] considered observable,” p. 146); others are nonsensical (“together the North Star and Algol defined the meridian over Siena at 9:30 pm on November 29, 1466,” p. 176). She is quite right, however, in identifying Albert and Thomas as strong opponents of the idea that images and symbols can add efficacy to the natural powers of talismans and amulets, which derive in their view from the manifest and occult qualities of their material composition. Seals, sigils, scenes, and shapes have significance only to intelligent beings. Consequently, they can enhance the power of a charm only through the collaboration of a demon, and, almost certainly, an evil one. According to Quinlan-McGrath, Ficino achieved a “stunning upset” (p. 159) of this sound and saintly teaching with his physics and chemistry of talismans.

Underlying Quinlan-McGrath’s analysis is the assumption that there existed uniform or standard beliefs and degrees of belief among people who consulted astrologers and consumed forecasts. As the variety of subjects and practices so far considered suggests, the assumption is not very plausible. Among the capital sources of disagreement were the problems of necessity (do the stars force outcomes or only bring pressure to bear?) and physicality (do they exert force and pressure directly or merely advertise outcomes produced by other means?). The multiplication of species on which Quinlan-McGrath relies supposedly impresses an exact image of celestial appearances on terrestrial receptors or talismans. But owing to the precession of the equinoxes, a planet that, astrologically speaking, occupies the midpoint of a zodiacal sign remains among the stars of the constellation belonging to the previous sign. Thus the astrological “sun in Leo,” where it is particularly strong, corresponds to the astronomical sun, the real sun, in Cancer, where the moon has its home.

One way used to overcome this awkwardness was to interpret the astrological information as signs, not causes, and to claim that the physical evidence favors signs over constellations. But then the species from the constellations have no direct bearing on astrological outcomes. Although this scruple does not seem to have weighed with Quinlan-McGrath, it bothered believers at the end of the fifteenth century. Pico devotes many pages of his encyclopedic attack on astrology to exposing the contradiction between a theory of physical influence, such as Ficino taught, and a practice of artificial signs, and to enlarging upon the “utmost stupidity or great malice” of astrologers who refused to acknowledge the difficulty.3

3. Thought Policing

Since the purpose of the HO and the CI was to combat new and threatening heresies, they do not bother with fifteenth-century books. The only person mentioned earlier in this review who figures in the inquisitorial documents is Ficino. But although his De vita coelestis comparanda (1489) contained many things animadversione digna (p. 238) and appeared on several unofficial lists together with his Opera omnia among suspect or confiscated books, he never secured a place on a Roman Index. Apparently the censors considered him a classic author, like Ptolemy or, closer to home, the poet Giovanni Pontano, whose writings on astrology replied to Pico from a position close to Ficino’s, and so was grandfathered out of the indexes. However, like many other authors, his position was shaken by Sixtus V’s thunderbolt Coeli et terrae creator (1586), which prohibited all astrology, and conscientious owners of astrological works gave them up. One of these former owners petitioned to read them on the unpersuasive ground that “he had no taste for other studies” (p. 2762).

Astrology proved particularly difficult for the thought police. The strict constructionist who hoped to eliminate “judicial” astrology—predictions of the fates of individuals via horoscopes and elections—faced the difficulty of purging it from books rich in such “natural astrology” as applications to navigation and agriculture (through weather forecasts) and medicine (through anticipations of plague). The intricacy of the problem appeared especially when the predictions of the two sorts of astrology gave coherent outcomes, as in the judicial specification of the death of an individual in a plague “naturally” foreseen. Physical astrology in the form promoted by Ficino complicated the situation further, since it claimed to be natural; yet it dealt with the fates of individuals and also, and perhaps more worrisome, challenged the Christianized Aristotelianism on which the Church founded its theology.

Paul IV thought to cut through these several knots by banishing all books dealing with judicial astrology. The protests his tough stand caused forced the replacement of the general proscription by actions against individual books until the Council of Trent issued a subtly qualified ban as Rule IX of its Index of 1564. The rule addressed judicial astrology together with geomancy, chiromancy, necromancy, incantations, auguries, and so on; but whereas it prohibited all writings on these subjects, and also writings on judicial astrology that “dare to affirm with certainty [certo] the outcome of a future event dependent on human will,” the insertion of certo appeared to allow predictions that restricted themselves to tendencies and probabilities. This was to retire to something close to the standard scholastic position, astra inclinant non necessitant.

Rule IX remained in force for over two decades before Sixtus issued his Bull prohibiting judicial astrology absolutely. He died before he could promulgate the new Index in which he incorporated his Bull; luckily his successor, Urban VII, immediately quashed it (“without doubt the most significant deed during the ten days of his pontificate,” p. 463) and so kept the Tridentine Index in force until the Clementine Index (1596) firmly established Rule IX. Sixtus’ Bull also stood, however, creating the administrative mess mentioned earlier, until Urban VIII reaffirmed it in his Inscrutabilis of 1631. This could hardly have stopped the practice of judicial astrology. As everyone knew, Urban, who was almost as besotted with astrology as Ludovico Sforza, freed Tommaso Campanella from an inquisitorial dungeon to shield the papal apartments from a solar eclipse using procedures recommended by Ficino. Because of the confusion surrounding the status of judicial astrology, its practitioners brought before the Holy Office could plead ignorance of the state of affairs as a defense, and escape with an admonition, fine, or brief exposure in the stocks.

The vagaries in the official attitudes towards astrology can be followed in the many documents devoted to Cardano, who began his career as a forecaster in 1534 with an almanac in the style of Novara. As a native of Milan, he naturally offered astrological reassurance of a long reign to the current Sforza duke, the Habsburg puppet Francesco II. That was a bad guess: Francesco died the following year, bringing the surviving semblance of Sforza rule to a definitive conclusion. Nonetheless, Cardano became famous as a specialist in medical astrology. He collected and analyzed the birth charts of celebrities to improve the empirical basis of his art. He entertained Neoplatonic and magical notions akin to Ficino’s. In short, he practiced astrology in the round and wrote about it voluminously.

The censors found much to criticize in Cardano’s books. Many of the documents printed by Baldini and Spruit are censurae, detailed consultants’ reports specifying offending passages; but, since Cardano’s clientele included many cardinals, his works escaped censure until the 1570s, long after most of them had been published. And even then the censors only placed them on unofficial lists to be banned donec corrigantur. Subsequent negotiations for corrections to be made by Cardano himself identified 122 serious errors, to which he did not respond adequately; and all his works apart from medical books alighted on the Clementine Index still in need of correction. Because of strong pressure from people wishing to read them, the censors made an effort to purge the books, but no officially sanctioned emendations ever appeared. As Baldini and Spruit observe, the mass of censurae concerning Cardano’s books makes “a kind of experimental garden” (p. 1037) for anyone interested in the thorny struggle between ecclesiastical censorship and early modern thought.

The documents about the natural magic of Giovan Battista della Porta make a good addition to the garden of inquisitorial delights. He first came to the attention of the Holy Office in 1574 during its examination of the charges against the Neapolitan astrologer Vincenzo Vitale. Two years later the HO sentenced Vitale to life imprisonment, which it soon commuted (as was customary) to detention in his hometown. Meanwhile, Della Porta was in and out of jail, and in 1578 the inquisitors prescribed a little light torture to move the case along. Somehow they divined without recourse to the rack that he did not practice necromancy and released him after a purgatio canonica, which required only an oath that he was innocent of the charges leveled at him. Later the Inquisition called him in over his Magia universalis. The trial again ended in a whimper. Magia naturalis was allowed but only in one edition, that of 1583, and then only if its owner crossed out a recipe for a salve that gave its users the sensation of participating in a demonic Sabbath.

Although it contains no astrology, judicial or otherwise, it would be negligent not to report the views of the sixteenth-century censors about Copernicus’ De revolutionibus (1543). It seems to have attracted censorial authority primarily when bound together with its synopsis, the Narratio prima (1540), whose author, Georg Joachim Rheticus, had the misfortune to be a heretic. However, although both books received nominations for expurgation, and an alert Dominican censor in Naples observed that Scripture did not describe a Copernican universe, nothing happened. Another consultor, Benedetto Giustiniani, a Jesuit, answered that Scriptural passages could be read variously, and recommended leaving the problem of world systems to the disputes of philosophers. Giustiniani’s answer has the peculiar interest that, when acting as a consultor to the HO in 1616, he joined his colleagues in judging the Copernican system to be contrary to Scripture and absurd in philosophy. No doubt there is an episode worth exploring here.

There are reasons to think that Baldini and Spruit’s work of supererogation has not received the study it deserves in the Anglophone world. WorldCat gives no location for it in London. Isis, the main English-language journal for the history of science, did not review it until three years after its publication.4 An article on della Porta and the Inquisition that just appeared in the British Journal for the History of Science does not mention his compromising association with the astrologer Vitale, or his several incarcerations before and during his trial.5 The author could have enriched his article, which emphasizes diversity of opinions within the censorial apparatus, with details of the punishments proposed for Vitale. The recommendations, listed under the name of each consultant, were: torture, abjuration, and banishment to the galleys; torture, abjuration ex vehementi, beating, galleys or perpetual imprisonment; abjuration, perpetual imprisonment (the opinion of two consultants); and the worst punishment available. The cardinals, more lenient than most of their consultants, settled on abjuration ex vehementi and perpetual incarceration, that is, banishment to his hometown. In the case of Mario Cioffi, arrested with della Porta but without a whiff of necromancy, kinder consultants recommended abjuration ex levi; release with abjuration and an obligation to give alms; release after salutary penance (three opinions); the same, plus a charitable contribution; the same, plus an admonition to stay clear of “such suspects” (as della Porta?)(pp. 1541–1542).

It is no punishment to read through the volumes reviewed here. Azzolini’s stories are instructive, Quinlan-McGrath’s ideas provocative, and Novara’s predictions as useful as they ever were. The treasure-trove of inquisitorial documents is both an inspiration to scholarship and a monument to the grandiose and generous program of collecting, classifying, correcting, and controlling the world’s literature for the general welfare. Every society, even open ones, has an interest in suppressing books and ideas it considers dangerous. But then, responsible regulators of the marketplace of ideas must operate under rules flexible enough not to stultify the minds they are intended to protect. With more money, more censors, more expurgators, the CI might have been able to produce a corpus catholicum, a list of reading matter fit for the faithful. An unofficial but influential anti-Index of this sort, the influential Biblioteca selecta, was compiled by a Jesuit, Antonio Possevino. It outdid the strictest official censors by examining such minutiae as printers’ devices and rubricated letters for hints of heresy. It is now fashionable to say that the Devil is in the details. Works like Possevino’s Biblioteca and the inquisitorial documents in the Archive of the Congregation of the Doctrine of the Faith are promising places to look for him.



Robert Westman, The Copernican Question (Berkeley: University of California Press, 2011), 56–61, 87–93, 529.


A brief history of the decipherment of the ceiling from Warburg to Quinlan-McGrath may be gathered from the editor’s notes to Fritz Saxl, La fede negli astri, ed. Salvatore Settis (Turin: Boringhieri, 1985), 478–483.


Giovanni Pico della Mirandola, Disputationes adversus astrologiam divinitricem, 2 vols., ed. Eugenio Garin (Florence: Vallechi, 1948–52), vol. 2, book viii, chaps. 2–3, pp. 238–239.


Paula Findlen and Hannah Marcus. 2012. “Science under Inquisition: Heresy and Knowledge in Catholic Reformation Rome,” Isis 103: 376–382.


Neil Tarrant. 2013. “Giambattista della Porta and the Roman Inquisition: Censorship and the Definition of Nature’s Limits in Sixteenth-Century Italy,” British Journal for the History of Science 46 (Dec): 601–625, esp. 619–621.