Reading Health in the Stars Politics and Medical Astrology in Renaissance Milan* MONICA AZZOLINI In fifteenth-century Italy (much as now) the election of a Pope was a momen- tous event, one that could be predicted with the help of one of the most com- mon prognostic practices of the time: horary astrology. On 20 July 1492 Ludovico il Moro, then the acting duke of Milan, wrote to his most promi- nent court astrologer to make inquiries regarding the health of Innocent VIII, a Genoese pope unsympathetic to the Milanese Duchy. Ludovico wrote to his personal astrologer Ambrogio Varesi da Rosate asking him to foretell if the Pope’s illness would result in death or not. For want of a nativity chart (genitura), Varesi cast a horoscope for the time of the inquiry, and reported to Ludovico that the position of the planets in the sky indicated that Innocent VIII was likely to die either on August 3, or sometime between August 10 and 11.1 * I wish to thank H. Darrel Rutkin and Nancy Siraisi for their valuable comments on an early draft of this essay. My research on the Sforza manuscripts housed at the Bibliothéque Nationale de France, Paris, has been made possible by a Fieldwork Fellowship from the Australian Academy of the Humanities and a grant from the Faculty of Arts and Social Sciences at the University of New South Wales. I wish to thank these two institutions for their support. 1 Archivio di Stato, Milano (henceforth indicated as ASMi), Autografi, Medici, cart. 219, Ambrogio Varesi da Rosate to Ludovico, Milan, 20 July 1492: Illustrissimo et Excellentissimo Signore, per satisfare ala domanda del pontefice quale la excellentia vostra per una soa me fece e fume presentata heri circa 21 hora, dale quale in qua con piu dilligentia et studio ho saputo, ho considerato et revoltato il sito de li corpi celesti in cello e loro influxo alhora de la domanda, che fu laltro heri a doe hore de note quando g[i]onseno le lettere et insiema examinato la interrogatione sua perche me ignota la nativitate de es[s]o pontefice, rivoltando insiema ancora el signatore grande del pastore e principale dela fede christiana in la revolutione de li anni del mondo, quali secondo alchuni astrologi sono il Sole con Marte, et secondo altri Mercurio con Iove et il Sole, insoma ritrovo, si havendo respe[c]to alhora de la interrogatione de la excellentissima signoria vostra, in la quale Marte fu significatore cum Iove per essere Marte in el caso suo et Iove ancora sotto li rag[g]i del Sole, la Luna sotto Terra, coniuncta per generale aspecto al sole signore del la casa de la infirmitade et Iove signore de lo as[c]endente adusto, et fra 25 di coniuncto cum Marte in la interrogatione signore de la casa de 184 Monica Azzolini Innocent VIII died on July 25, earlier than predicted, but neither Lu- dovico nor his brother, Cardinal Ascanio, questioned the reliability of their source. Rather, Ludovico relied on Varesi’s reassurances in the same letter that the next Pope would be favorable to the Sforzas.2 A week later, however, Ludovico was far more cautious. He reported to Ascanio that Varesi’s further investigations at the time of Innocent VIII’s death suggested that their plans for the election of the new Pope could be jeopardized because of avarice or disloyalty.3 Accordingly, he encouraged his brother to be liberal towards la morte, es[s]o pontefice dovere morire. Il medesimo si denota per la interrogatione per essere stato Venere sua significatrice alhora de la revolutione combusta et coniuncta con lo significatore dela morte, quale in el presente anno che denotava la morte. Il medesimo ritrovo per la revolutione de li anni del mondo quale incominzo ad 10 de marzo, in la quale fu il significatore del pastore dela fede christiana insiema con Venere damnati per adustione del Sole in la casa de infermitade, per la quale cossa si denotava la morte del pastore de la fede chiristiana. Il quando mo debia morire, ritrovo per la presente interrogatione che debe sequire la morte aut fra 22 di che sara ad 10 o 11 de Auosto [i.e. Agosto] per la coniunctione de Marte con Iove in la domanda, aut fra 15 di per il quarto aspe[c]to dela Luna ad Venera signora in la domanda dela casa dela morte, in modo che per via dela domanda me si demostra non possa pervenire insino ala fine de Auosto, che cosi el nostro signore dio per la soa clementia permetta et conceda si per il bene publicho chomeo per il privato. (Transcription mine, with some addi- tions and modernized punctuation for ease of reading.) This letter is also transcribed in full in Gabotto 1889, 382f. (with some minor differences in the transcription of the original). Gabotto interprets the astrological prognostication as having been re- quested by the Pope himself. Given the often tense relationship between Milan and the Papacy, the delicate nature of astrological prognostications of this kind, and the reference to the fact that Varesi could not draw the nativity chart of the Pope (and thus did not have essential information for the accurate prognostication of his death) it is obvious that what Ascanio and Ludovico were doing was to probe the stars in the hope of anticipating the Pope’s death, a highly illicit practice. For the more fa- mous case of the prognostication of Pope Urban VIII’s death, and the trial that en- sued, see Dooley 2002. As is well known, in 1631 Urban VIII issued a long bull against astrological prediction later published under the title Inscrutabilis. On Varesi, see Cuomo 1987, and Azzolini 2004. 2 Ibid.: Quanto ad la intelligentia et amicitia, quale ha ad seguitare con lo succesore del pontefice, respondo che la Illustrissima Signoria Vostra sara bene amata et gli parturera comodo pero che partendosse la Luna ultimatamente da Iove, fu recepta dal Sole da sestile aspecto da casa propria del Sole, che denota la Excellentia Vostra dal successore essere amato chomo uno amico o vero parente quale alogiasse in casa uno altro per farli conzo et servitio. Et questo e quanto in questo poco tempo ho potuto cavare per la virtute del celo et corpi celesti in queste cosse inferiore. De quale natura et quale conditione habia ad essere questo successore per la brevitate del tempo non ho ancora potuto comprendere; non perdero tempo per considerare et intendere questa parte, et trovato habia alcuna cossa, subito daro avisso ala Illustrissima Signoria Vostra a la quale humiliter me richomando. (Transcription mine, as are all translations in this article, unless otherwise noted.) 3 ASMi, Sforzesco, Potenze Estere, Roma, cart. 106, Ludovico to Ascanio, Vigevano, 28 July 1492: ne l’hora in la quale è scripto che ’l pontefice è manchato ascendeva  Reading Health in the Stars 185 other cardinals and cautious in choosing his allies. Confident in the influence of the stars, Ascanio exerted his political power among the Roman curia and succeeded in getting Rodrigo Borgia elected as Pope Alexander VI. Varesi’s prognostication is only one of many examples of astrological practice that can be traced in contemporary sources. Such stories reveal a worldview in many ways alien to our own, and reveal much more besides.4 They show how in the Renaissance politics was played at various levels, not only by making alliances and strengthening diplomatic ties, but also by using predictive arts such as judicial astrology (of which horary astrology was one mode of practice), which were believed to rest on sound ‘scientific’ princi- ples.5 Among other things, therefore, this account is a story of the role of as- trology in fifteenth-century political life. Varesi’s interrogation reveals how horary astrology was skillfully exploited in political circles and suggests that, far from being irrelevant to our understanding of Renaissance Italy, astrology played an important role in shaping its history. This paper explores some of the ways astrology played a political role in the lives of early modern elites. Judicial astrology was not the only branch of astrology employed to investigate somebody’s health by studying the position of the stars and the planets in the heavens. Different competing astrological practices intersected in the Renaissance, all of which were employed to varying degrees in fif- teenth-century Italy. The link between medicine and astrology had been es- tablished in classical times, and physicians since had relied on medical Cancro, quale è ascendente de la Reverendissima Signoria Vostra, e che in la revolutione de li anni del mundo el medesimo Cancro era in mezo del celo, che è la casa regia; le quale due cose portendeno felicità alla Reverendissima Signoria Vostra in questa creatione. È vero che ne l’hora de la interrogatione mia dice che Saturno era in aspecti col significatore de la Reverendissima Signoria Vostra; la quale cosa fa che si possa dubitare che la Signoria vostra possa essere offesa o per avaricia o per infedeltà. For the context of this letter and the events surrounding the election of Cesare Borgia as Pope Alexander VI, see Pellegrini 2002, esp. I: 375- 403. I rely here on Marco Pellegrini’s transcription. Ludovico’s letter is quoted at p. 376. 4 On the long durée of astrology as a body of knowledge, and qualifications as to its relevance in contemporary society, see the perceptive remarks of Anthony Grafton in Grafton 2000, 70-83. 5 Judicial astrology comprised natal, horary, and electional astrology. Natal astrology included the practice of ‘annual revolutions’ in which the astrologer calculated the client’s prospects for the coming year on the basis of their birth chart; see Thomas 1973, 338f. In the Middle Ages and the Renaissance there was considerable confu- sion between interrogations and elections. The two were originally interrelated but distinct practices. Interrogations were used to determine the outcome of specific questions in terms of a figure (horoscope) drawn up for the moment when the ques- tion was formulated. Elections, on the other hand, studied the planetary positions in order to establish the most suitable time for beginning an activity. See Page 2002, 30-35, and Burnett 1996, 369-382, esp. 375f. 186 Monica Azzolini astrology to treat their patients.6 This is true also of Renaissance physicians, who turned to astrology in order to offer both a prognosis of a patient’s ill- ness and a remedy for their malady, as well as to explain the disease causally. Although not all rulers and doctors embraced the practice of astrology uncritically or to the same degree, the existence of contemporary critiques of astrological practice and medical astrology does not seem to have convinced many physicians and their patients to reject medical astrology.7 This essay seeks to explore the way in which Renaissance elites relied upon astrological prognostication in matters of health. In doing so, it seeks to illuminate the role of medical astrology within the private and political spheres of Italian Renaissance courts, and put renewed emphasis on the vitality and importance of this tradition. My analysis will concentrate on the practice of astrological medicine among one of the most important fifteenth-century European political elites: the Sforzas. I will approach this question within the context of ideas concern- ing the relationship between the stars and the human body that had emerged in the period 1200–1500. In attempting to explore this complex topic, I will first offer a concise overview of the major tenets of medical astrology and a brief outline of some of its key texts. I will then investigate this tradition by comparing university learning and court culture in Renaissance Milan. This comparison will reveal similarities and continuities between the university curriculum and the theoretical body of knowledge in the possession of the court physician-astrologer. I will then conclude my essay with a case study of 6 The first important ancient author to draw attention to the analogies between medi- cine and astrology was Ptolemy: in representing astrology as a stochastic techne, that is, an art which had carefully developed rules of conjecture, he said that it was like medicine. See Ptolomy 1940, I.2, especially pp. 13-19. 7 As Anthony Grafton and Nancy Siraisi warn, generalizations about medical astrol- ogy in the Renaissance are hazardous. See Grafton and Siraisi 2001, 110. Only fur- ther research on court astrology will be able to establish to what extent the Italian elites and their doctors relied on medical astrology. The fact that in the late fifteenth century there were a number of authors who openly contested the reliability of medical astrology seem to suggest that medical astrology was reasonably popular. This seems also testified by the rich manuscript and printed tradition. The most powerful critique of medical astrology was arguably that of Pico della Mirandola in his Disputationes adversus astrologiam divinatricem, first published in 1496, which dedicated a number of chapters to the topic. See Pico della Mirandola 1946, espe- cially pp. 322-363. The debate generated by Pico’s work certainly contributed to the renewal of medical astrology and engendered debate over the Galenic theory of the critical days. In relation to Pico, see Bellanti 1498, quest. 14, art. IV (An critici dies a luna sint). For an example of later debates see Fracastoro 1538 and Turini 1542. Turini was the archiatra of Pope Paul III. See also Steven vanden Broecke’s essay in this volume for two seventeenth-century examples: Giovanni Antonio Magini and Andrea Argoli. For a useful discussion of the some of the medical literature of the time and some ensuing debates, see also Grafton and Siraisi 2001, 69-131, esp. 77- 92.  Reading Health in the Stars 187 Gian Galeazzo Maria Sforza’s illness that will illuminate the practice of medical astrology at court. My analysis will exemplify the uses to which as- trological medicine could be put among leading elites. But before discussing the specific case of Milan, I will provide a general overview of the classical and medieval background to Renaissance medical astrology. 1. The Long Life of Medical Astrology The literature on medical astrology has a venerable tradition that cannot be fully explored in the space of a short essay.8 This medical literature formed part of the flowering of astrology in Renaissance Italy more generally, and has been transmitted down to us in hundreds of different manuscripts and printed sources. The basic principle behind medical astrology was that the stars and planets exerted a noticeable influence on everything on earth, in- cluding plants and stones (Grant 1987; North 1987). A corollary to this the- ory was the principle that each part of the human body was influenced by a different sign of the zodiac and that each of the ‘openings’ of the body were influenced by one of the planets (Burnett 1996, 376). This theory was often visualized in medieval and Renaissance texts through drawings such as the “zodiac man” and the “microcosmic man.”9 Theories of influence were par- ticularly significant for the practice of phlebotomy as well as surgery, and could be extended to the administration of medicaments. As medication was composed of herbs and minerals, the relative influence of the signs of the zodiac and the planets on the medication’s ingredients was another factor for the physician to consider when administering the treatment. 8 To the best of my knowledge there are no studies in English that address systemati- cally the genre of medical astrology. Although single texts, or groups of texts, have been studied to some degree, medical historians have paid relatively little attention to this genre, and both the manuscript and printed traditions of the late Middle Ages and the Renaissance still await a major study. For illuminating studies on specific aspects of the topic (largely restricted to England), see Mooney 1984; Carey 1994; French 1994; French 1996; O’Boyle 1991; Grafton and Siraisi 2001. Ficino’s De vita libri tres is arguably one of the most significant works of medical astrology of the Italian Renaissance. The literature in German is more extensive. See Weisser 1981; Weisser 1982; Müller-Jahncke 1985; Schadewaldt 1988; Welker 1988. 9 A survey of the iconographic tradition goes beyond the scope of this study. For a very popular example of a zodiac man, see Ketham 1491. The vernacular edition of Sebastiano Manilio is printed in Ketham 1493. For an example of microcosmic man see Page 2002, 52. See also Clark 1979. 188 Monica Azzolini One last aspect that pertained to medical astrology was the theory of critical days, which was related to solar and lunar cycles.10 It was believed that these cycles determined the days when crises would occur in an illness; for this reason, the manifestation of certain symptoms on certain days would allow the physician to make a more accurate prognosis as to the outcome of the illness. Because it was related to predictable cycles and cohered with the main tenets of astronomy, natural philosophy, and humoral theory, the theory of critical days proved particularly popular, and as such can be traced in medical and non-medical writings alike. As a specific genre of medical writing, the literature on critical days can be further subdivided into two categories: one includes texts that are solely devoted to the theory of critical days; the other comprises texts where the authors embrace elements of this theory in their treatment of specific ill- nesses. As a classical example of the first category, one can mention the nu- merous commentaries or texts based closely on Galen’s De diebus criticis, one of the most important and popular texts of medical astrology. Pertaining to the second category, one can look, for instance, at the numerous treatises on fevers that employ the theory of critical days in prognostication, as well as medieval and Renaissance commentaries on Hippocrates’s Prognostica, ps- Hippocrates’s De medicorum astrologia, and some of the aphorisms included in ps-Ptolemy’s Centiloquium.11 In addition to the transmission of these texts from classical antiquity, the Middle Ages inherited a rich tradition of Arabic and Jewish medicine that incorporated the theories of critical days within its theory and practice. Among the most influential Arabic works that propounded the theory of criti- cal days, one should mention Avicenna’s Canon, Averroes’s Colliget, and Arabic commentaries on ps-Ptolomy’s Centiloquium, while significant con- tributions were also offered by the Jewish tradition of the De luminaribus et de diebus criticis of Abraham ibn Ezra, and the Liber de febribus of Isaac Israeli.12 10 The study of the phases of the moon seems to have predated classical times and is common in popular lore. Lunaria, namely predictions or recommended activities for each day of the moon, as well as zodiologia, namely predictions based on the sign of the zodiac in which the moon falls at a given time, had wide circulation. For the Latin tradition, see Svenburg 1963. For the medieval tradition see Means 1993. 11 For an excellent survey of some of these texts, see dell’Anna 1999, I: 9-11. The ps- Hippocratic De medicorum astrologia was widely available in Pietro d’Abano’s translation. For a printed edition, see d’Abano 1485. On this text, see Thorndike 1960; and Kibre 1978. On medical prognosis in the Middle Ages see also the recent article by Demaitre 2003. Demaitre, however, questionably argues for the minor role of astrology in medical prognostication. 12 See Avicenna 1555, Liber IV, fen. 2, tract. 2 (De diebus crisi et horis eius), cap. 1- 10, fols. 449r-451r; and Averroès 1574, Liber IV, cap. 40 (De diebus criticis), fols. 76v-77r. For an extensive treatment of the Arabic tradition of the critical days see dell’Anna 1999, I: 10 [n. 15-16], and 83-153. Abraham ibn Ezra and Isaac Israeli  Reading Health in the Stars 189 Despite the striking variations between authors and within different medical traditions (classical, Arabic, and Jewish), some elements of these astrological theories remained common to all. For instance, the passage of time as determined by the position of the planets in the heavens was an essen- tial element of medical prognosis. The theory of critical days hinged on the relationship between the macrocosm (the heavens) and the microcosm (hu- man beings), expressing a close connection between illness, time, and the position of the luminaries and planets. According to one of its basic princi- ples, for example, acute fevers were due to the movements of the moon, while chronic fevers were due to those of the sun.13 The popularity and lon- gevity of these theories within medical circles is attested not only by the nu- merous extant medical manuscripts, but also by the fact that the theory of critical days became one of the favorite topics of seventeenth-century aca- demic prolusions and disputations (dell’Anna 1999, I:11). Having offered a brief overview of medical astrology’s main tenets, I shall now move to the investigation of its study at university and its use at court. draw more extensive connections between astrology and the theory of the critical days. See Ibn Ezra 1507, fols. 71v-75v (with the title Liber luminarium et est de cognitione diei critici seu de cognitione cause crisis), and Israeli 1515, fols. 203v- 226. For the manuscript tradition of Isaac’s treatise on fevers see also Richards 1984. Isaac’s Theorica in the same volume contains further references to the theory of the critical days and astrological medicine (Isaac 1515, Liber X, cap. 1-13). 13 Avicenna 1555, IV, fen 2, tract. 2, cap. 2 (De causa dierum crisis et periodorum eius), fol. 112vb states: Plures quidem homines posuerunt causam in mensuratione temporum crisium egritudinum acutarum ex parte lunae, et quod virtus eius est vir- tus incedens in humiditates mundi causans in ea species alterationis & adiuvans ad maturandum & digerendum: aut ad contrarium secundum praeparationem materiei [sic]. Et significant in hoc per dispositionem fluxus aquarum & refluxus & augu- mentationem cerebrorum cum augumentatione luminis in luna & velocitate matura- tionis fructuum, arborum & herbarum cum plenilunio eius, seu apparitione eius. Et dicunt quod humiditates corporis patiuntur a luna quare diversificantur dispositio- nes earum secundum diversitatem dispositionum lune. Haly’s commentary to ver- bum 60 of ps-Ptolomy’s Centiloquium notes that: [Ptolomeus] dixit quod esse solis in morbis prolixis sit sicut esse lune in acutis: quorum maius tempus erit orbis lune et in prolixis orbis solis. On the action of the sun and moon in relation to the theory of critical days, see also Ysaac 1515, Theorica, Liber X, cap. ix, fols. 54r-55r (De diversitate diei cretice secundum numerum et cursum lune). See also dell’Anna 1999, I:124. 190 Monica Azzolini 2. Reading Health in the Stars: From the University to the Courtly Library In Italian universities, the teaching of astrologia (by which we should under- stand both astronomy and astrology) seems to have been foundational for the three major disciplinary areas in which the university curriculum of a student in ars et medicinae was structured: mathematics, natural philosophy, and medicine.14 Lectures in astrology were certainly part of the curriculum at Pavia, the Studium of the Duchy of Milan, and the Rotuli of the university generally indicate at least two teachers of astrology in any given year.15 2.1. Astrological Medicine at Pavia Although we have a reasonably complete list of the names of the professors who taught at Pavia, unlike those of Bologna, the Pavia statutes of the Col- lege of Arts and Medicine do not provide much information regarding the texts studied. From the high mobility of the students and professors at Pavia, we can presume, however, that their course of study must have been similar to that of other universities such as Bologna, Padua, Pisa, and, to some ex- tent, Paris.16 Before the Studium at Pavia was established, the citizens of the Duchy of Milan who wanted to pursue a university degree had no choice but to study ‘abroad,’ often choosing Bologna and Paris as their preferred institu- 14 For a discussion of the importance of astronomy/astrology in these areas, see Rutkin 2002, 1f.; ch. 2 (on astrology and natural philosophy); and ch. 3 (on astrology, medicine, and mathematics). 15 To give only some random examples: the Rotuli of 1399–1400 indicate the follow- ing: M. Blazio de Parma legenti Philosophiam moralem, naturalem et Astrologiam, Magistro Iohanni de Catelonia legenti Astrologiam, and M. Francisco de Crispis legenti Astrologiam. See Majocchi 1905–1915, I: 421f. The Rotuli of 1425 report under the rubric “Ad lecturam Astrologie”: M. Petrus de Montealcino, legat in die- bus festivis, and M. Antonius de Bernadigio, legat astrologiam cum salario flor. XL. Bernadiggio appears also on the same Rotuli as teacher of phisica, while Pietro da Montalcino also taught ad lecturam extraordinariam Pratice. See Majocchi, II/1, 221f. By 1439 Bernadiggio had risen considerably within the academic ranks and received 300 florins for his teaching ad lecturam ordinariam Medicine, but he was also still teaching astrologia. Pietro da Montalcino does not appear in the Rotuli, whereas a Stephanus da Faventia also taught astrologia together with Bernadiggio; Majocchi 1905–1915, II/1, 395. 16 It would be a mistake, of course, to assume uncritically that these universities did not have their own specificities. This, however, should not prevent us from assum- ing that the basic teachings were similar. One should also mention that despite the regular bans issued by most cities forbidding their citizens from studying at other Studia, this ban was often ignored or circumvented, at least partially. Often students spent time at another university before returning to Pavia to graduate, as in the case of the physician-historian Paolo Giovio; see Zimmerman 1995.  Reading Health in the Stars 191 tions (Pesenti 1990, esp. 460f., and 467-470).17 Considering that in its early days some of the most influential professors of medicine had previously trained at Bologna, it seems safe to assume that the curriculum at Pavia was modeled to some extent on that of Bologna. For our purposes, it is particularly significant that the Bolognese medical students had to study all three books of Galen’s De diebus criticis during their first three years, and that as part of their training in astrology in their third and fourth year they studied medico-astrological texts such as ps- Ptolemy’s Centiloquium with Haly’s commentary and Guillelmus Anglicus’s De urina non visa.18 Although we cannot compare the Pavia and Bologna curricula in their entirety, at least for astrology there is substantial evidence that the curriculum at Pavia may not have differed considerably from that of Bologna.19 Evidence in support of this thesis can be gained by examining the 17 In the initial pages of this article, Tiziana Pesenti examines the early teaching at the University through two prominent teachers: Albertino Rinaldi da Salso and Gio- vanni Capitani da Vittuone. Here Pesenti argues that from Albertino da Salso on- wards, because of his training at the University of Bologna, the University of Pavia showed a marked non-astrological character: “Da Albertino in poi la fisica soppi- antò decisamente, nella produzione dei maestri pavesi, l’astrologia. Questa rimase la scienza della corte, mentre i professori dello Studio cominciarono da allora ad affiancare agli autori medici testi di filosofia naturale.” And later, “L’interesse di Albertino per problemi di una fisica del tutto aliena da valenze astrologiche derivava dalla sua formazione bolognese ed anche la tendenza che egli esercitò sulla scuola pavese, isolando la tendenza astrologica rappresentata da Maino [Maineri], va inquadrata in un ambito più generale di relazioni tra Pavia e Bologna” (Pesenti 1990, 468f.). Although Nancy Siraisi (quoted by Pesenti) has drawn attention to the different medical models offered by Pietro d’Abano and Taddeo Alderotti, respec- tively the two most significant representatives of the universities of Padua and Bo- logna in the Middle Ages, one should be cautious to draw the conclusion that these medical models were mutually exclusive. Furthermore, Pesenti seem to see astrol- ogy as one monolithic practice, a concept that fails to recognize the complexities of this discipline, and ignores its profound relationship with medicine in the theory of the critical days. As I will discuss below, one could hardly argue that astrology was not part of the Bolognese curriculum. On Bologna, see Federici Vescovini 1998, I: 193-223. On Paris, see Jacquart 1992, 121-134. The astrological teachings in the Bolognese curriculum have been recently contexualized in Rutkin 2002, ch. 3. Rut- kin presents a cogent and persuasive argument in favor of the centrality of astrology within the Bolognese curriculum. Although he does not address the issue of medical astrology in detail, his argument reaffirms the centrality of astrology within the Bolognese curriculum. On Astrology in the curriculum of Italian Renaissance uni- versities, see now Grendler 2002, 415-426. 18 For the medical curriculum of Bologna, see Malagola 1888, 274-276. 19 “In astronomia primo anno legantur algorismi de minutis et integris, quibus lectis, legatur primus geometriae Euclidis cum commento Campani. Quo lecto, legantur tabulae Alfonsi cum canonibus. Quibus lectis legatur theorica planetarum. In secundo anno primo legatur tractatus de sphera, quo lecto legatur secundus geometriae Euclidis, quo lecto legantur canones super tabulis de linerijs. Quibus lectis, legantur tractatus astrolabij Mes[sa]chale [sic]. In tertio anno primo legatur 192 Monica Azzolini notebook of Giovanni Battista Boeri, a medical student who also studied as- trology at Pavia in the years around 1484.20 Among other things, his notebook contains passages from a number of Arabic astrological texts, including Mesahalah’s (Māshā’allāh’s) De revo- lutione anni mundi and Haly Abenragel’s Tractatus de electionibus; a prog- nostico by the Milanese court physician Gabriele Pirovano for the year 1484;21 a hypothetical exercise on how to cast a nativity; some unidentified medical rubrics of clearly practical orientation, such as “Electio pro sanguine missione” and “Electio pro pharmacis recipiendis”; drawings of the division of the phases of the moon after Sacrobosco’s Sphera; Johannes de Lineriis’s Canones (Canones primi mobilis Johannis de Lineriis); a treatise on physi- ognomics; Guillelmus Anglicus’s De urina non visa (De urina non visa et de concordia astrologiae et medicine et caeterae); a rubric entitled “De prog- nosticatione morborum per crisim et alia signa”; a section that illustrates as- trological aphorisms from the Liber Almansoris in the translation of Plato of Tivoli (Explicantur amphorismi in astrologia ab almansore saracenorum rege editi de arabico in latinum a platone tiburtio translati);22 some other nativities, and some medical recipes. Sacrobosco’s Sphera, John de Lineriis’s canons on the Alphonsine ta- bles, and De urina non visa correspond to texts set for the second and fourth year in the four-year astrology course at Bologna.23 From this manuscript we can infer that these astrological and medical texts were studied at Pavia. We can also speculate that Arabic texts such as Almansor’s Aphorisms, Mesaha- Alkabicius, quo lecto legatur Centiloquium Ptolomei cum commento haly [sic]. Quo lecto legatur tertius geometriae, quo lecto, legatur tractatus quadrantis. In quarto anno primo legatur quadripartitus totus, quo lecto legatur liber de urina non visa. Quo lecto legatur dictio tertia almagestj” (Malagola 1888, 276). 20 British Library (henceforth BL), Arundel 88. On this manuscript, see also Thorndike 1923–1958, IV: 542, and Kristeller 1963–1996, IV, 127a. I plan to dis- cuss this and other astrological manuscripts extensively in a forthcoming study on medicine and astrology at the court of Milan. 21 BL Arundel 88, fol. 29v: Explicitus iudicium de 1484 editum a clarissimo artium et medicine doctore Ducali medico scriptum autem ab originali primo per me Johan- nes Baptistam Boerium artium et medicine studentem, nec non etiam astrologiam audientem. At fol. 39v repeats a similar explicit adding that he is from Tabia (most likely modern Taggia, a small Ligurian town) and the son of “doctor domino Leo- nardi”. The manuscript was compiled largely in 1484. Elsewhere in the manuscript he says that he is “profugus a Papie” because of the plague and resided in the Lig- urian city of Valenza. 22 This section seems to correspond loosely to BNF Ms Lat. 7307. Capitula d’Almansor, Latin trans. of Plato of Tivoli (XIII sec), fols. 18r-21v. This manuscript was in the possession of the duke of Milan; see discussion below. 23 “In secundo anno primo legatur tractatus de sphera, quo lecto, legatur secundus geumetrie Euclidis, quo lecto legantur canones super tabulis de linerijs. […] In quarto anno primo legatur quadripartitus totus, quo lecto, legatur liber de urina non visa” (Malagola 1888, 376).  Reading Health in the Stars 193 lah’s De revolutione anni mundi, and Haly Abenragel’s Tractatus de elec- tionibus may have found their way into the curriculum of medieval universi- ties. A number of these texts, furthermore, had obvious practical applications in medicine proper. Texts like the De urina non visa and other anonymous rubrics such as the “Electio pro sanguine missione,” the “Electio pro pharma- cis recipiendis,” and the “De prognosticatione morborum per crisim et alia signa” are all clearly related to the practice of medical astrology, and were therefore particularly significant for Boeri. So far I have illustrated the kind of astrological medicine that in all likelihood was taught at Pavia, and indicated that some of these texts coin- cided with those in the Bolognese curriculum. This in itself can help us gain a clearer understanding of the training of a Lombard physician after concluding his studies at the Studium of Pavia. In order to gain further insight into the intellectual and professional background of Lombard physicians, I wish to turn now to the duke’s private library. 2.2. The Duke’s Private Library A comparison of the texts listed in the Bologna statutes with the astrological and medico-astrological texts housed in the ducal library at the Castle of Pavia shows a significant overlap. Among the texts listed in the Bolognese astrology curriculum,24 the following volumes also appear in the inventories of the ducal library: one copy of Johannes de Sacrobosco’s Algoritmus minutis et integris;25 two copies of Campanus’s commentary on Euclid’s Ge- 24 See note 19 above. 25 Pellegrin 1955, 166. Bibliothéque Nationale de France (henceforth BNF), Ms Lat. 7363, Consignatio A, n. 409. Pellegrin’s study is based on three inventories, dated 1426 (Consignatio A), 1459 (Consignatio B), and 1469 (Consignatio C, which in- cludes only the texts owned by Galeazzo Maria Sforza that were added to the ducal library). Two other inventories have recently been discovered in the notarial ar- chives at Pavia. These two inventories date to 1488 (inventory D) and 1490 (inven- tory E). On these inventories, see Albertini Ottolenghi 1991; and Cerrini 1991. Inventory D and E both list 947 items. Inventory A, which lists 988 books, offers a very detailed description of the books, often describing the colour and material of the cover, the kind of supporting materials (parchment or paper), their size and other precious details (damaged binding, illuminations, etc). It also includes, quite unusu- ally for the time, both incipits and explicits of most of the books. All these details have contributed to the identification of a number of books in French and European libraries. Unless stated otherwise, I refer only to Inventory A in this article. It is in- teresting to compare this manuscript’s content with Ms A. 51, sec. XIV, in the Bib- lioteca Comunale Archiginnasio, Bologna, which includes: Sacrobosco’s Tractatus de algorismo, Tractatus de sphere, and Tractatus de arte quadrantis; Robert Gros- seteste’s Tractatus de computo; the anonymous Cautelae in divinationum computa- tione and Tabulae de computo, and ps-Boetius’s Tractatus de doctrina scholarium. 194 Monica Azzolini ometry;26 The Toledan Tables;27 multiple copies of Johannes de Sacrobosco’s Sphera;28 a copy of Robertus Anglicus’s Tractatus quadrantis;29 a commen- tary on Alcabitius’s Liber introductorius ad magisterium iudiciorum as- trorum;30 a copy of ps-Ptolemy’s Centiloquium;31 and a copy of Ptolemy’s Almagest in the translation of Gerard of Cremona.32 Among the texts ex- pounding the theory of critical days in the ducal library at the Castle of Pavia we can count an Isagoge Ioannini et de diebus cresitis [sic],33 and a text by Galen entitled Super de crisi (that could have contained either Galen’s De crisibus or the De diebus criticis, or possibly both).34 Additional works rele- vant to the practice of medical astrology include: Tabula medicorum ad in- veniendam lunam in signis gradibus et minutis mediocris voluminis coperti 26 Pellegrin 1955, 130. A n. 255 and n. 256, respectively Campanus super geometria Euclidis copertus corio pavonacio levi ad modum parisinum, and Euclidis ge- ometria cum planisphero Tholomei copertus corio rubeo levi (now BNF, Ms Lat. 7214). This second manuscript not only contains Euclid’s Geometry with Cam- panus’s commentary, but also Messahala’s Libellus interpretationum de interroga- tionibus, Thebit ben Corat’s De motu octave sphere, and Ptolomy’s Planispherium. 27 Pellegrin 1955, 166. A n. 410 (BNF, Ms Lat. 7409: Liber tabularum tolentinarum parvus copertus assidibus cum fondo rubeo). 28 Pellegrin 1955, 136f., 166, 287. A n. 290 (BNF, Ms Lat. 7267); n. 409 (BNF, Ms Lat. 7363); n. 971 (BNF, Ms Lat. 7400). 29 Pellegrin 1955, 137. This text is also part of A 290, BNF, Ms Lat. 7267, entitled Alfreganus cum tractatu in spera et Alberto de mineralibus copertus corio rubeo. Other astrological texts included in this manuscript include an anonymous Liber de iudiciis in astrologia (possibly Haly’s text); Canones in motibus super celestium corpora (possibly De Lineriis’s Canon); Thebit ben Corat’s De recta imaginatione spherae coelestis; and Alfraganus’s Liber de aggregationibus scientiae stellarum. 30 See Pellegrin 1955, 136. A n. 287: Scriptum super Alchibizio cum quibusdam tabulis astrologie in papiro forme magne non ligat. cum assibus. The inventory of 1459 (Consignatio B) adds the name of the commentator John of Saxony, leaving no doubt that we are dealing with Alcabitius’s Introductorius and not any other work by the same author. 31 Pellegrin 1955, 129. A n. 251 (BNF Ms. Lat. 7307). The Centiloquium with the commentary of Haly (Ali Ibn Ridwan, ca. 998-1067) became one of the most influ- ential texts within this tradition. For a list of manuscripts in the major European li- braries, see dell’Anna 1999, 137 [n.2]. For the first incunabulum, see Opera astrologica varia (Venetiis, 1493), which contains the Centiloquium together with other Arabic and Jewish astronomical texts. This printed edition, whose contents mirror to some extent Ms 7307, must have been based on a manuscript of the kind analyzed in Pesenti Marangon 1978. For a discussion of this manuscript, see also Rutkin 2002, ch. 3, 139f. For a modern critical edition of the Greek text, see Pseudo-Ptolomei fructus sive centiloquium, in Boer 1952. 32 Pellegrin 1955, 138. A. n. 292 (Ms Lat. 7258). Almagestum Tolomei copertum corio rubeo levi. 33 Pellegrin 1955, 170. A n. 431. Possibly now BNF, Ms Lat. 7038, a manuscript ver- sion of Taddeo Alderotti’s commentary on the Isagoge. On its content, see dell’Anna 1999, 17f. 34 In the Middle Ages the main tenets of these two texts are often combined in the Aggregationes de crisi et creticis diebus; see O’Boyle 1991.  Reading Health in the Stars 195 carta,35 Tabule pulcherrime pro contemptu de sole et luna,36 and Tabula quedam de luna,37 together with numerous other Arabic and medieval texts that included medico-astrological concepts such as Avicenna’s Canon, Averroes’s Colliget, and Razes’s Liber Almansoris.38 The ducal library obviously constitutes a privileged source of infor- mation on texts the court physicians may have consulted. The comparison with the Bolognese curriculum, however, reveals much more. It indicates those texts that in all likelihood were also at the core of the curriculum of medicine and astrology at Pavia. The correspondence between the holdings in the ducal library and texts studied and taught at Northern Italian Studia should not be surprising. Some of the most esteemed court physicians held positions at the University of Pavia. Furthermore, the duke himself heavily influenced the politics of the Studium. The constant intervention of the ducal authority in the life of the Studium is well documented, not only regarding the appointment of profes- sors to the Studium, but also in relation to litigation between members of the university, regular impositions upon a collegium to accept a new member, or upon the Studium to confer a degree.39 Additionally, during Ludovico il Moro’s rule, Ambrogio Varesi da Rosate, his most famous court astrologer, was put in charge of university hires, most likely strengthening any astrologi- cal leaning at the Studium (Cuomo 1987, 28). Clearly there was no sharp separation between university and court medicine, and there is substantial evidence demonstrating that a number of prominent physicians moved com- fortably between these two spheres.40 3. Physicians at the Bedside: The Practice of Prognostication So far I have examined the perceived importance of astrological medicine within the university curriculum of Pavia as well as at the Sforza court. It was in everyday practice, however, that the full political implications of medical 35 Pellegrin 1955, 136. A n. 288. 36 Pellegrin 1955, 294. B n. 103. 37 Pellegrin 1955, 294. B n. 105. 38 See Pellegrin, 1955. There were multiple copies of all these texts: Avicenna’s Liber Canonis, A 481, 487, 489 (?), 491, 801, 802; Averroes’s Colliget, A 436, 484; Razes’s Liber Almansoris, A 455, 490. 39 The University of Pavia is the sole Italian university to maintain a collegiate system to the present day. For the intervention of the duke, see Sottili 1994, 146f., and pas- sim; and Sottili 1982. 40 See Azzolini 2001. See also Crisciani 2003, and, on Italian physicians more gener- ally, Palmer 1981 and Pesenti 1997. 196 Monica Azzolini astrology emerged. It is therefore time to turn to private correspondence that bears witness to the practice of medical astrology in fifteenth-century Milan. As noted before, one of the staples of astrological medicine was the theory of critical days. In what follows I will concentrate on one particular incident, in which we can observe the practical application of the theory of critical days and other types of medical astrology. My case study centers on the illness and death of Gian Galeazzo Maria Sforza (1469–1494), duke of Milan from 1476–1494. The various phases of the illness were characterized by persistent fevers that eventually led to his death in 1494. In reading the thick web of correspondence between the physicians and courtiers attending the duke, his wife Isabella d’Aragona, and his uncle Ludovico, we can gauge the personal and political implications of the duke’s health. Only at his death in 1494 did Gian Galeazzo’s uncle and custodian, Ludovico il Moro, offi- cially receive the title of duke of Milan. And it seems no coincidence that it was in 1494 that France, with the support of Ludovico, invaded Italy, occu- pied Naples, and finally—in an unexpected turn of events—attacked its erst- while ally Ludovico.41 From the correspondence it is evident that the disease, which never fully abandoned the young duke from an early age, followed a regular cycle. References to the day of the illness are very common in the correspondence. In addition, the fevers alternated between cold and hot. Furthermore, while the disease was progressing, reference was often made to the expulsion of excess humors. All these elements are present in the treatment of fevers in Galen’s De diebus criticis. Additionally, one can presume that Gian Galeazzo’s physicians erected a celestial figure (or horoscope) at the time of the onset of the disease, its decumbiture.42 It is therefore worth following some of this correspondence. Gian Galeazzo often wrote personally to his uncles Ludovico and As- canio to inform them about the progress of his illness. In the fall of 1483, for example, Gian Galeazzo himself informed his uncle Ascanio of his poor health with the following words: As I wrote to you in other letters, today—which is the fourth day—a certain alteration (al- teratione) appeared, which was accompanied by cold and hot fever. All day yesterday and tonight we felt very sick and unwell until the 9th hour, to the point that it was too much for our complexion and young age. Nonetheless, around the 9th hour it started to get better and we have been feeling quite well for the remaining part of the day. For this reason we rest our hopes in the divine clemency that we will sail to a safe harbor and be free from this condi- tion. And to reassure you we wanted to inform you, so that if you have read otherwise you 41 On the events preceding the invasion of Italy, see the numerous essays in Abulafia 1995a. The full political implication of Gian Galeazzo’s death and his relationship with Ludovico (including Ludovico’s alleged poisoning of Gian Galeazzo) are ex- plored fully in a forthcoming article. 42 For an illuminating analysis of this practice in the late sixteenth century, see Grafton and Siraisi 2001, esp. 69-72.  Reading Health in the Stars 197 can have some peace of mind and you can communicate this to the illustrious duke of Calabria [Alphonso of Calabria, later Alfonso II, King of Naples; father of Gian Galeazzo’s future wife Isabella].43 The following day Ludovico wrote to his brother Ascanio with more news on the health of their nephew. Gian Galeazzo was still sick, but the physicians were hopeful he would soon recover: Around the 17th hour this Illustrious Lord started feeling cold, and then hot, and this condi- tion persists up to now, the 24th hour. The paroxysm has been much less significant than that of the day before yesterday and although the matter expelled (materia peccante) is of such a nature that shows the illness to last a few more days, nonetheless the doctors hope to bring His Excellence to a safe port. They have not yet ordered to give him the remedy as they are waiting for Nature to take its course, which so far has been very successful, and to let the present conjunction pass, because, as the moon is [in conjunction] with Mars, this would negatively affect the remedy (faria furere la medicina).44 As noted earlier, astrological medicine was also associated with the admini- stration of herbal treatments. Within this framework, some medications needed to be administered at certain times and not others so as to ensure maximum efficacy and the positive influence of the stars. The unfavorable conjunction of the moon with Mars would have had a negative effect on Gian Galeazzo’s health and therefore the doctors had suggested waiting a few days before administering it. The disease was explicitly set within an astrological framework on other significant occasions. For instance, on 2 October 1483 Gian Galeazzo himself wrote as follows to his uncle Ascanio: 43 ASMi, Sforzesco, Potenze Sovrane (henceforth SPS), cart. 1464, n. 329. Gian Galeazzo Maria Sforza to Ascanio Sforza, Milan, 28 September 1483: Come per altre ve scripsimo essendoci sopravenuta hogi el quarto giorno certa alteratione cum la febre freda et calda in vero tutto heri et questa nocte passata fin ad le nove hore ci dede grande ambastia et passione in tanto che ne pariva pur troppo alla compressione [sic] et età nostra de adolescentia. Nondimeno circa le nove hore commenzo ad fare meglioramento et cusi per tutto hogi siamo stati assay bene. <Per la tal> cosa speramo in la divina clementia reuscirne ad bono porto et presto remanere libero. Et pero ad vostra consolatione vi ne havemo voluto dare noticia advio se fusse stato scripto altramente ne possiati remanere cum lanimo reposito et de cio ne communicarere cum lo Illustrissimo Signor Duca de Calabria. (Transcription and emphasis mine.) 44 ASMi, SPS, cart. 1464, s.n. Ludovico il Moro to Ascanio, Milan, 29 September 1483: Circa le xvij hore sopragiunse el fredo ad questo Ill.mo Signore et poy el caldo el quale gli dura ancora ad questhora 24. El parocismo e stato asay minore de quello de lalterheri et benche la materia peccante sia de natura che dimonstra dovere protrahere el male qualchi di, nondimeno sperano li medici redurre la excellentia sua ad bon porto. Non se e ordinato ancora darli medicina per expectare quello possi fare la natura da se la quale fin qua se e aiutata asay bene et etiam per lassare passare la presente coniunctione in la quale trovandosi la luna con marte faria furere la medicina. (Transcription and emphasis mine.) 198 Monica Azzolini In reply to what you wrote in your letters of the second-last day of the previous month, ex- pressing your sympathy for our alteration and fever, we say that we are absolutely certain that your Highness and the illustrious lord the duke of Calabria our father were very upset. In the beginning [this illness] caused us much pain and discomfort, but since Sunday we have felt much better and we are now without fever. Since yesterday we have had a few lines, and we believe the reason is the combustion of the moon. Thank God around the 22nd hour it went away and we hope in His clemency that we will soon be free from it as it has been much more moderate than in the beginning.45 The terms alteratione, compressione, parocismo, and materia peccante in the correspondence are all part of a specialized technical vocabulary used to ex- plain the theory of critical days (dell’Anna 1991, I: passim). The combustion of the moon refers to the moon’s position in relation to the sun: if it is within eight and a half degrees, it is combusta (i.e. burnt), an aspect that often leads to complications (Burnett 1996, 376). Far from presenting a technical and lucid medical explanation, how- ever, these letters use a lightly textured medical jargon. While they do in- clude medical theories and terminology, they do not discuss it in the same lucid and compact prose that one finds in the medical treatises; but this is hardly surprising. As the record of oral conversation, and the result of a medical discourse aimed at people with no medical training, these stylistic and rhetorical features are to be expected (cf. Crisciani 2001, 695f.).46 Gian Galeazzo’s illness fits the mould of Galenic fevers. According to the Galenic tradition, the cycle of a patient’s pathology started from the mo- ment the fever appeared. The cycle lasted twenty days, and it could be re- peated numerous times.47 Gian Galeazzo told Ascanio that his alteratione appeared on the fourth day of the cycle. According to the theory of critical 45 ASMi, SPS, cart. 1464, n. 332, Gian Galeazzo to Ascanio, Milan, 2 October, 1483: Respondendo ad quanto me scrive la signoria vostra per le soe del penultimo del passato condolendose de la alteratione nostra de la febre dicemo che siamo certissimi che sua signoria insieme con quello Illustrissimo signore Duca di Calabria nostro patre ne habino havuto displacentia et in vero al principio la ce dede grande affano et ambastia. Pur da domenica in qua semo stati assai meglio et infine tutto martedi continuamente facessemo meglioramento et se trovamo in tutto mondi de febre. Da heri in qua ne havimo pur sentita uno pocho delche credemo sia stato casone la combustione dela luna. Pur per gratia del nostro Signore dio circa le xxii hore hogi ne fumo remasti necti et speramo in la sua clementia che ne remaneremo presto liberi perche la e stata molto piu legere che non fu in li principij. (Transcription and emphasis mine.) 46 Crisciani’s argument that theory does not appear in this type of correspondence is based on a small sample of correspondence from the Milanese archives. A larger study reveals variations of the kind examined here that complicate the picture. 47 Galen makes a distinction between the mensis medicinalis and the mensis lunaris. See dell’Anna 1999, ch. I; and Galen, De diebus decretoriis, 3.9, in Kühn 1964– 1965, IX, 928-933. Galen’s treatment of this theory did not receive a sustained cri- tique until the sixteenth century, when the Milanese physician Gerolamo Cardano openly challenged Galen’s ‘medicinal month’; see Grafton and Siraisi 2001, 89f.  Reading Health in the Stars 199 days, the fourth day was considered a dies indicativus, namely a day when the symptoms of the disease appear and allow the physician to establish the illness’s progression.48 In the De diebus criticis Galen establishes a complex set of relations between the progression of the illness and the signs that ap- pear on the patient’s body. The signs can be positive or negative, and this will establish the final outcome of the illness. Galen’s theory of critical days incorporates Greek humoral theory and semiotics within a mathematical framework, indicating a primary develop- mental factor of the illness and its manifestation in the concotio of the hu- mors. The sooner the patient shows the signa concotionis the better, as the illness will be shorter.49 Hence, Gian Galeazzo’s allusion to compressione (by which he probably meant complessione) and his uncle’s reference to ma- teria peccante are explicit references to humoral theory and to the idea that, according to the theory of critical days, the early expulsion of excess humors was an essential part of the illness’s progress toward recovery. According to the tenets of classical astrology, the moon was associ- ated with the element of water, and, as a consequence, with all the liquid elements of the human body, namely its humors.50 Despite the strong rela- tionship between the position of the moon and the progression of the illness, other factors could intervene and upset this delicate balance. Among these factors, ps-Ptolemy mentioned food (cibus), anger (ira), and physical exer- cise (labor), but also, significantly, the position of the other planets.51 The 48 According to this theory, the dies indicativi are the fourth, eleventh, and seventeenth day of the cycle (which, as noted, starts at the appearance of fever). The seventh, fourteenth and twentieth days are the dies iudicativi, namely those days when the doctor will be able to determine the outcome of the illness (these are, in effect, the critical days, the dies critici). If the cycle were protracted beyond 120 days, the fe- ver would be declared chronic; otherwise it was considered acute. For a treatment of these complex aspects of the theory, see dell’Anna 1999, 48-76. See also Aphorisms 2.24 in Hippocrates 1979, Bk 4, 115; and Galen, De diebus decretoriis 2.3, in Kühn 1964–1965, IX, 848-852. 49 Galen, De diebus decretoriis, 1.11 in Kühn 1964–1965, IX, 818-831, esp. 818-820. 50 For the influence of the moon, see Galen, De diebus decretoriis, 3, esp. 2-7 in Kühn 1964–1965, IX, 901-913, and note 13 above. 51 Ps-Ptolemy 1493, fol. 112rb-va, Verbum 60. dierum creticorum et determinabilium egri: Albaharim sane et certe sunt hore quibus declarantur mutationes morborum ad bonum vel ad malum velociter. Et sunt loca lune in angulis quadrati conclusi a circulo directo. Alterationes vero que precedunt has et indicant sunt loca lune in angulis habentibus XVI latera et hoc postquam precesserit esse egretudinis, secundum equalitatem sine interpretatione, et non acciderit aliquid exterius quod conturbet infirmum, destruat vel noceat ut cibus, ira, labor et huiuscemodi. Cum igitur invenerimus huic fortunam scilicet in predictis angulis, hora principii egritudinis tam de fixis quam de erraticis significabit alterationem prosperam. Si vero infortunam alterationem adversam nisi fuerit egritudini ipsa infortuna contraria in suo hain [sic] scilicet infortuna. Luna vero in his angulis significat 200 Monica Azzolini conjunction between the moon and Mars mentioned in Ludovico’s letter was not deemed a positive one: Mars’s excessive dryness would have exerted an influence opposite to the moon’s positive effect on the humors.52 Many more letters on Gian Galeazzo’s health followed over the years until he died in 1494. Always prone to poor health, he fell seriously ill in 1492 and a wealth of correspondence offers invaluable insight into the pro- gress of the illness that ultimately led to his death. From 1492 until the mo- ment of his death, his health never improved. According to the ducal physicians Gabriele Pirovano and Nicolò Cusano, who took care of Gian Galeazzo in the years and months preceding his death, this was due both to the influence of the heavens and the concurrent eclipse, but also to Gian Galeazzo’s own ill-fated nativity: Illustrious and Excellent Lord most Distinguished, after the notice [we sent] at the 17th hour, the Illustrious Duke woke up again at about the 18th hour and we think he did not look re- stored as we expected after his meal and some sleep. Rather, he looked very weak, and, hav- ing given him a bit of broth, soon after he had a violent jump and a tremor in his stomach and he let off some air from his mouth; this was accompanied by some noise of water that one could hear moving. Further, he had a twinge and a sense of suffocation that affected the liver and the spleen with a rather sharp pain in the liver if pressed. But it stopped, and the noise appeared to descend to the intestines, which is a worrying sign in medicine for we have very few remedies [for it.] But we will carry on [caring for him], especially because of the terrible influence of the heavens, both because of the eclipse and the direction of his nativity as his Highness knows from past experience because “etiam in medicina solus casus virtutis est per se signum malum.” We will continue with the proper and necessary remedies for as long as we can, and we won’t fail to inform you of that which ensues and make provisions for that which happens and may occur easily in these circumstances. And if this happens, it is not in our power to restore his health, but he will be in clear danger of dying immediately—God forbid.53 morbos acutos. Sol vero prolixos. Et similiter omnis planeta secundum mores proprios significat. (Emphasis mine.) 52 See Ptolemy 1940, I, 5: “[…] because two of the four humours are fertile and active, the hot and the moist (for all things are brought together and increased by them), and two are destructive and passive, the dry and the cold, through which all things, again, are separated and destroyed, the ancients accepted two of the planets, Jupiter and Venus, together with the moon, as beneficent because of their tempered nature and because they abound in the hot and the moist, and Saturn and Mars as produc- ing the effects of the opposite nature, one because of his excessive cold and the other for his excessive dryness”. Also, Ptolemy 1940, III, 10-12. See also Galen, De diebus decretoris, 3. 6 (in Kühn 1964–1965, IX, 911f.): Si enim ad planetas tem- peratos steterit, quos jam nominant, salutares faustos ac bonos dies producere, si ad intemperatos, graves molestosque. On the influence of the moon in different signs of the zodiac, see Galen, De diebus decretoris, 3. 5-6 in Kühn 1964–1965, IX, 908-913. 53 ASMi, SPS 1464, n. 195, Pavia, 20 October, 21 hour, 1494. Nicolò Cusano and Gabriele Pirovano to Ludovico: Illustrissime et excellentissime domine nostre colendissime, dopo lo adviso de hore 17 lo Illustrissimo duca se resveglio circa hore 18 et ad noy non ce parso redonato alla virtute secundo che speravamo dovesse fare dopo tale refectione et sompno [sic] ma ne pariva quodammodo  Reading Health in the Stars 201 The stars were not with Gian Galeazzo (and probably never had been). On October 21 a series of letters to Ludovico announced his death. On the fol- lowing day Ludovico proclaimed himself duke of Milan and took official control of the duchy at a crucial point in the history of the Italian peninsula. The disastrous results of his rule, most notably the French invasion of Italy in 1494, can hardly be overestimated (Abulafia 1995b). Milan was occupied by the French army in 1499 and Ludovico was forced to flee. Finally captured while trying to cross the mountains and seek refuge with the emperor, he died in the Castle of Loches in 1508 (Abulafia 1995b, 24). It seems that neither Ludovico nor his astrologers and physicians could predict the events that had ensued. 4. Conclusion As this essay illustrates, astrology could be employed in many different ways in the Renaissance. At court, however, astrology was often closely connected to both political practices and the health of the ruler. Without a doubt, medi- cal astrology retained a certain prominence in both the curricula of Northern Italian universities, and in cities, as well as in the daily practice of Italian physicians. Far from being solely a theoretical body of knowledge, medical astrology was regularly employed in the treatment of illness and in medical prognostication. Its conjectural nature was disguised by fashioning astrologi- cal medicine in the language of astronomy and mathematical computation. At the same time, the complex nature of the art allowed the physician significant flexibility for adjusting the course of his prognostication and hence of his treatment. For this reason, medical astrology offered more reassurance than other branches of medicine. By determining the influence of the planets on the human body and thus resorting to different astrological practices, the phy- opressa piu la virtute et multo debile et havendoli dato uno pocho de stilato fra pocho li sopravene uno salto et moto tremulo nel stomaco cum una gurgitatide di ventositate et strepito di aqua che sensibilmente se sentiva movere et li faceva dolore et suffugatione che comunicava al fidago et ala milsa cum dolore maggiore nel fidago al tochare; pur cessava et pariva descendesse tale rugito ad le intestine, cosse che sono di grande timore in medicina, et che haveriemo poche o nulle medicine. Continuaremo maxime stando etiam lo influxu horribile di celo et per ecclipse et per directione di la nativitate cum se vostra excellentia per il passato perche etiam in medicina solus casus virtutis est per se signum malum noy continuaremo li remedij apportuni et necessarij quanto poteramo et non li mancharemo di previssione ali casi futuri et provedere ad quello poria accadere continue et sopravenire di novo facelmente in tale caso che poy accadendo non saria in nostra libertate la reductione ma seria in manifesto periculo di manchare subito che dio non voglia. (Transcription and emphasis mine.) 202 Monica Azzolini sician-astrologer could both foretell the progression of an illness and offer the more risky life or death prognostications. It was only political acumen, how- ever, that could have saved Ludovico from his fate. References 1. Manuscript Sources BOLOGNA BIBLIOTECA COMUNALE DELL’ARCHIGINNASIO Ms A. 51, sec. 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