Introduction: arguing about the stars on the southern side of the confessional divide

Arguing about the stars has rarely been more controversial and dangerous than in the early modern period in Europe, especially in Catholic countries, in a time when old and novel conceptions of the heavens, planetary models and theories of celestial motions and influences were intensely debated, revised and scrutinized for philosophical soundness and religious conformity.¹ In the hundred years or so that witnessed the birth and censorship of the Copernican theory; the execution in Rome of the most passionate defender of post-Copernican cosmology, Giordano Bruno (1548–1600), and the rise and fall of Galileo Galilei's (1564–1642) fame linked to his novel interpretation of the book of nature, the Catholic Church created some of the most powerful instruments of cultural control and educational conformity ever seen: the Inquisition, the Index of Forbidden Books and the vast network of Jesuit schools that spread from Rome and the Iberian peninsula across the globe.²

The special issue we are introducing explores how this constellation of intellectual, religious and political pressures – embodied in institutions such as universities, colleges and courts – significantly influenced the shaping of cosmological speculation in Counter-Reformation Europe. Together, the contributors go beyond the well-documented and widely studied cases of censorship and inquisition, to offer concrete case studies that show how the production of cosmological knowledge in early modern Catholicism was by itself the result of a negotiation between religious–cultural policies and scientific endeavours. Our methodological proposition is that these endeavours cannot be fully understood through the historiographical framework of censorship and the progress of scientific rationality alone; rather, all of these elements taken together should be seen as integral components of a complex sociopolitical process of transformation of the modern cosmological outlook.

In the past, the history of science embraced the idea of a clear-cut confessional and epistemological divide between the Catholic world, destined to halt scientific progress, and the northern European area, open to innovation, including in astronomical matters, identified primarily through the expansion of the Reformed creeds. This historiography often connected the two otherwise distinct themes of religious reform and the emancipatory advance of knowledge as cause and effect.³ Yet episodes of religious intolerance and pseudo-scientific obscurantism also proliferated in Protestant Europe. They are symbolized by the massive witch-hunts that often combined religious authority, popular superstition and scientific advice.⁴ Moreover, academic ostracism, which deeply influenced the difficult relationship between modern scientific culture, religion and politics, was not exclusive to Catholic environments. One thinks of Utrecht in the 1640s, when powerful Calvinist theologians censored Henricus Regius's (1598–1679) Cartesian medicine because of its implications for the immortality of the soul and other dogmas.⁵ A well-known episode of theological–political censorship took place many years after the period we are investigating in this thematic issue, in late seventeenth-century Prussia, with state attacks on intellectual freedom. It was in these circumstances that Immanuel Kant penned his famous The Contest of Faculties (1798) in response to the persecution of his views on religion ‘within the limits of reason’, which he saw as a more general problem affecting all philosophy, sciences and university disciplines.

While both the Catholic and Protestant sides of the confessional divide experienced conflicts between scientific inquiry and religious and political agency, the centralized structure of the Catholic Church – enforced through the formidable censorship and propaganda mechanisms of the Holy Office, the Inquisition and the Jesuit college network – imposed a qualitatively different and more rigorous level of control over scientific discourse. While this increased regulation was its central aim, as we suggest here, the dynamics of early modern science and the knowledge of the stars in predominantly Catholic countries cannot be reduced to simple schemes. Not only did the boundaries between different ideological, cultural, religious and vernacular communities shift over time, as confessional identities were transformed and multiplied, but also top-down attempts to establish intellectual conformity in scientific, philosophical and moral matters were variously articulated by both the institutions and the proto-scientists, and even had unexpected consequences, including the opening of inter-confessional spaces for the exchange and circulation of ideas.⁶ Indeed, early forms of cosmopolitanism can be seen as a response to confessional clashes that could not be resolved within the limits of religion. This thematic issue explores significant cases of the cultural politics of science in contexts strongly influenced by religious and confessional tensions and changes. At the same time, we aim to offer a picture that avoids oversimplifications and allows the complexity of historical, cultural, and scientific processes to emerge.⁷ To be sure, attention to complexity should not mean adopting a naive perspective, one that indulges in celebration and apology.⁸ On the contrary, the reader should be reminded of the conflictual nature of the sociocultural and religious tensions that deeply altered the form and development of astronomical and cosmological knowledge in the early modern period.⁹

Scientific developments in Northern Europe have all too often been explained as the consequence of a milieu shaped by the Reformation, by its practices, its spirit, its theology, or all of these together. The Merton thesis of the determining influence of Puritanism on the scientific culture of the early Royal Society is well known. Its success among historians has even inspired counternarratives by Catholic revisionists arguing for the relevance of Counter-Reformation spirituality as a key factor in modern science.¹⁰ Historians seeking to assess the Jesuits’ science against their image (from the Enlightenment through positivism and rationalist interpretations of the Scientific Revolution) as missionaries who sacrificed scientific integrity to propaganda fidei, a kind of militant effort to toe the party line in religious matters, have argued that their ideology was the main reason for the success of their scientific endeavours.

Other Protestant historians, following in the footsteps of Max Weber's diagnosis of the spiritual roots of capitalism, have argued that Calvinism was also responsible for the birth of modern science.¹¹ More recent inquiries into the Protestant camps (necessarily in the plural) have pointed to the importance of Melanchthon's legacy in Lutheran universities for the development of the study of the heavens in the post-Copernican era as an access to God's Providence.¹² These confessionalized accounts of modern science have tended to pit one confessional camp against the other, while neglecting the role of conflicts – intellectual, political, social and cultural – in the making of modern European culture, including the sciences, and in the emergence of secular and Enlightenment agendas. Binary and ahistorical approaches that essentialize confessional identities have too often reduced the image of science in early modern Southern Europe to either Jesuit education and scientific practices, or the struggle against the Inquisition and other forms of cultural coercion. Yet the history of science in the century of Girolamo Cardano (1501–76), Niccolò Tartaglia (1499–1557), Giovanni Battista Benedetti (1530–90) and Guidobaldo Del Monte (1545–1607) – to mention but a few of the most prominent innovators in matters of mathematics and mechanics of the sixteenth century – cannot be reduced to a simple opposition of competing fronts. This was an age of flourishing university institutions, such as Padua, where Averroism and other Scholastic legacies coexisted with novel anatomical and botanical studies, and visionary philosophies – such as the works of Bernardino Telesio (1509–88), Tommaso Campanella (1568–1639), Francesco Patrizi (1529–97) and Bruno. If we extend the investigation beyond Italy and consider other southern contexts, the picture becomes even more challenging and interesting. Our explorations in this special issue include the scientific inheritance in Renaissance Italy and Europe of the disappearing empire of Byzantium, where the new impulse to the study of the stars originated at the end of the fifteenth century; the Iberian peninsula, which was the epicentre of fundamental transformations in global relations and knowledge through colonial expansion; and the Kingdom of France, a fundamental theatre of state-led institutionalization of scientific research.

Through a collection of case studies, this special issue addresses the sociopolitical and confessional backgrounds that underpinned, informed and conditioned the production of cosmological knowledge in early modern Counter-Reformation and Southern European institutions. We address the following research questions.

How was early modern cosmology shaped and transformed by the interplay of political interests and religious agendas in the period of the Counter-Reformation, the expansion of courtly society and the formation of modern states? Why were so many intellectual and material resources invested in scientific endeavours related to the science of the stars?

Following closely on these previous questions, how did the various institutions of knowledge – universities, academies, colleges – inform and condition the cosmological discourse? In what ways did cultural policies direct the cosmological inquiry, and through what institutional mechanisms?

The contributors to this volume explore how knowledge institutions of various kinds – such as universities, academies, colleges and observatories, but also the state and the court, and the Church and its apparatus, especially the Inquisition and the Index – constituted a space of both transmission and obstruction, transformation and negotiation, of received knowledge in constant tension with the new conceptions and intellectual breakthroughs. Overall, we aim to enrich the history of knowledge dynamics by looking at the interplay of ideas, actors and contexts, considering both the macro-contexts – societal formations and churches – that shaped the cultural life of knowledge institutions, and the micro-institutions – such as more or less established and formal circles and scholarly networks.

The first article in our collection, by Alberto Bardi, examines the profound significance of Johannes Regiomontanus's (1436–76) inaugural lecture at the University of Padua in 1464 within the broader context of Byzantine intellectual influence and Graeco-Arabic traditions in early modern Italian astronomical studies. Bardi argues that it is crucial to understand Regiomontanus's inaugural lecture within the framework of the cultural policies of Bessarion (1403–72) and his support for Regiomontanus at the University of Padua in the 1460s. Bessarion, heir to a hybrid scholarly lineage, saw in Regiomontanus's teaching and scientific activity an opportunity to reform astronomical studies by emphasizing the physical properties of the heavens and integrating Graeco-Arabic traditions, thus overcoming the separation of astronomy from astrology and the condemnation of astrology which had been propounded by Meliteniotes (1320–93) and accepted by Eastern theology.

The article also explores the broader implications of Regiomontanus's views for Renaissance mathematical sciences, considering the possible influences of both Bessarion and the humanist scholars of the time. Since Regiomontanus appears to neglect the richness of Arabic mathematics in his lecture, scholars have traditionally viewed him as pursuing an anti-Arabic Latinate programme.¹³ Bardi suggests, however, that this must be understood within the context of the intellectual tools and sources available to him. Since Regiomontanus acknowledges the importance of Arabic astronomy, it is far more likely that a limited number of Latin translations of Arabic mathematical sources was available to him at the time and that his omission should therefore be seen as unintentional. Ultimately, Bardi's study highlights the complex interplay of Byzantine, Greek and Arabic influences in the development of early modern European science, challenging simplistic narratives of cultural transmission and intellectual heritage.

In his paper ‘Medicine and the heavens in Padua's Faculty of Arts, 1570–1630’, Craig Martin discusses the evolving relationship between medicine and astrology at the University of Padua from the late sixteenth century to the early seventeenth. During this period, professors at the University of Padua debated the validity of astrology and its role in medical theory. The sources reveal a shift from an initial acceptance of astrology as part of medical practice to increasing scepticism among faculty members which, driven by the influence of Aristotelian natural philosophy, culminated in the decades between the 1570s and 1620s. Key figures at Padua, such as Girolamo Mercuriale (1530–1606), Alessandro Massaria (1524–98) and Cesare Cremonini (1550–1631), played an important role in critiquing astrological theories, particularly those relating to celestial influences on human health. Paduan scholars also distanced themselves from Jean Fernel's (1497–1558) account of the astral influence of epidemics, arguing that such influences were incompatible with the empirical observations of disease and the philosophical frameworks of Aristotle and Hippocrates. Despite these criticisms, astrology was not entirely dismissed at Padua, as political and intellectual currents in Venice in the 1620s led to the re-establishment of astrological teachings.

Pietro Daniel Omodeo's article examines the cosmology of Cesare Cremonini, a leading Aristotelian philosopher at the University of Padua during a time of intense religious conflict in Europe leading up to the Thirty Years War. Cremonini, a staunch defender of the university's autonomy against theological control and Jesuit competition, advocated the separation of philosophy from theology. His views were rooted in a secular and rationalistic interpretation of Aristotle, which he used to argue for the eternity of the cosmos, the absence of divine intervention in the world and the rejection of teleology. His commitment to keeping religious concerns out of philosophical inquiry reflected a broader cultural–political programme aimed at fostering tolerance and intellectual freedom at the University of Padua, a truly cosmopolitan institution with a diverse student body, including Catholics and non-Catholics.

As the protector of the multi-confessional German Nation of Artists at Padua, Cremonini played a decisive role in mediating religious conflicts among students. His efforts to maintain a secular academic environment were consistent with his philosophical stance, which emphasized the independence of reason from faith. Despite his conservative adherence to Aristotelianism, his work contributed to a cultural agenda that supported the free pursuit of knowledge, even when it clashed with the emerging scientific ideas of the time, such as those of Galileo. Cremonini's legacy is marked by his resistance to ecclesiastical authority, and his role in shaping a culture of intellectual autonomy at Padua makes him a significant figure in the history of early modern philosophy and science.

Luís Miguel Carolino's article explores the complex integration of Tycho Brahe's astronomical theories into the Jesuit intellectual framework in seventeenth-century Portugal, particularly at the College of Saint Anthony in Lisbon.¹⁴ This integration, Carolino shows, must be understood in the framework of the Counter-Reformation's strict cultural and religious policies – which were rooted in the strenuous defence of Aristotelian physics as functional to religious orthodoxy – and the Jesuit order's approach to Scripture, which advocated its literal interpretation. The Jesuits valued Brahe's system as a compromise between the outdated Ptolemaic model and the controversial Copernican heliocentric theory, which had been rejected by the Catholic Church. On the one hand, Brahe's system offered a solution to a number of challenges that observational astronomy and the Copernican planetary theory had posed to traditional Ptolemaic theory. On the other hand, Brahe was a Lutheran, and propounded a cosmology that openly contradicted the Aristotelian one by asserting the fluidity of the heavens.

The process of the reception of Brahe's cosmology by some of the fathers of the College of Saint Anthony in Lisbon was neither straightforward nor uniform, as it involved a careful balancing act between adherence to Catholic orthodoxy and recognition of the astronomical advancements that Brahe represented. Carolino shows that, at first, the Jesuits of the College of Saint Anthony selectively adopted Brahe's geo-heliocentric theory, while strictly confining his authority to the domain of mathematics. This selective acceptance highlights the weight of confessional concerns, since the Jesuits prioritized religious conformity over scientific exploration and limited Brahe's influence to areas that did not challenge orthodoxy. At a second moment, they tacitly incorporated elements of his cosmology, but justified them by reference to the teachings of the Fathers and without explicitly attributing them to Brahe. The article concludes that the Jesuits’ cautious reception of Brahe reflects broader tensions between science and religion during the Counter-Reformation, illustrating how confessional boundaries shaped scientific authority in early modern science.

In his article, Rodolfo Garau addresses the decline of astrology as a scientific practice in the early modern period. This tendency is often linked to a broader shift in the mentality of the gentry and the bourgeoisie, or to the emergence of the ‘new science’. Garau highlights the crucial role of patronage and the political dynamics of the French elite in this process of the marginalization of astrology from the French scholarly milieu by focusing on the career of Jean-Baptiste Morin (1583–1656), a prominent astrologer and professor of mathematics at the Collège royal. Astrology in early modern France was deeply intertwined with politics and power, with figures such as Richelieu and Mazarin using astrological predictions for political decision making and propaganda. Morin, appointed as a professor of mathematics at the Collège royal in 1629, gained considerable influence through his astrological consultations for powerful patrons, including Cardinal de Bérulle and Maria de’ Medici. Drawing on previously neglected evidence, Garau argues that Morin's appointment was meant to provide socio-cognitive legitimation to astrology, a discipline which had already become the target of criticism and censorship, while at the same time validating a belief system in which Morin's patrons were themselves invested.

However, the political turmoil of the Fronde, combined with the death or fall from power of his patrons, led to a decline in Morin's influence. This period also saw a change in the intellectual climate, with Pierre Gassendi (1592–1655) and his circle, advocates of the ‘new science’, publicly attacking astrology as outdated and superstitious. These criticisms played a significant role in the decline of astrology as a respected discipline in France. Garau argues, however, that the marginalization of astrology was not only determined by scholarly verdicts. These critiques also contained political elements that challenged Morin's presumed astrological advice to Mazarin and exploited the former's lack of patronage support due to political turmoil as well as the changing priorities of the ruling class. Ultimately, the marginalization of astrology was also deeply influenced by the shifting cultural and political investments of the ruling classes. This case study highlights the importance of understanding the social and political contexts in which scientific practices develop, and shows that the decline of astrology was closely linked to the broader cultural politics of seventeenth-century France.

Nydia Pineda de Ávila's article, ‘Universal enough: the politics of nomenclature in seventeenth-century selenography’, explores early modern selenography and shows that the practice and tools used to create a standardized and unified map of the Moon were deeply intertwined with the political and religious contexts of the time. Pineda shows that lunar maps, or ‘selenographies’, were not purely scientific products but also rhetorical and political instruments that reflected the broader cultural and ideological agendas of their makers. Her article focuses on two specific cases of lunar naming schemes developed by Michael van Langren (1598–1675) and Giovanni Battista Riccioli (1598–1671). Van Langren's selenography, produced in the context of the Spanish Netherlands, was embedded with political and confessional messages reflecting the imperial ambitions of the Spanish monarchy and the neo-Stoic philosophy prevalent in the region. His map, which named lunar features after prominent political and religious figures, was a means of both scientific observation and political communication.

Riccioli's selenography, part of his Almagestum novum, aimed to provide a comprehensive and universal basis for astronomical observation. Riccioli and his collaborator Francesco Maria Grimaldi (1618–63) developed a naming system that was less politically charged but still reflected the Jesuit emphasis on education, synthesis and the reconciliation of different scientific perspectives. Their nomenclature combined traditional and contemporary names, creating a map that served both as a technical aid and as a representation of the history of astronomy. Overall, the article argues that selenographies were multifunctional objects that served multiple purposes, advancing scientific, political, religious and cultural agendas. The universal aspirations of early modern lunar maps were shaped by the specific local and institutional contexts of their creators, making them deeply embedded in the ideologies of their time.

To sum up, this special issue addresses the sociopolitical and confessional backgrounds that underpin, inform and condition the production of cosmological knowledge in early modern contexts shaped by religious hegemonies other than the Reformation. We focus on the interplay between political and confessional agendas, and on the dynamics of transmission and obstruction, transformation and negotiation, of knowledge in institutional settings such as universities, colleges and academies. Overall, this special issue introduces the interpretive lens of cultural politics in order to reassess the historical interconnection between science and religion. It problematizes this relationship from the perspective of the hegemonic struggles between local and global powers that marked the fragmented political landscape of the time. We look at the tension between novel conceptions and established forms of knowledge. Specifically, we are interested in locating them in the encounter between the cultural politics of science and religious agendas at the intersection of politics (the court, the patronage system, the formation of nation states, the bureaucratization of states and so on), identities (in processes of confessionalization, struggles for intellectual innovation, the constitution of international networks of literati or local circles of like-minded people), and institutionalization processes (in university settings as well as in relation to new institutions such as scientific academies; in the book market and in editorial policies; within institutions of control and censorship, especially the Index and the Inquisition). In short, we look at the confessional and ideological struggles affecting science, which, given the complexity of the cultural landscapes involved, cannot be reduced to monolithic or blindly ideological programmes.