of Philosophy
University of Bologna
via Zamboni, 38
40126 Bologna, Italy
tel. +39.051.2098353
fax: +39.051.2098670 Email:

About this site

No. 11, May 1998
The passions of the atoms


No. 13 - Dec 2000 (PDF)

No. 12 - Sep 1999

No. 11 - May 1998

No. 10 - Jun 1997

Marta Cavazza on Susana Gomez Lopez, Le passioni degli atomi. Montanari e Rossetti: una polemica tra galileiani. [The Passions of the Atoms. Montanari and Rossetti: A Polemic Between Followers of Galileo], Florence, Leo S. Olschki, 1997.

Susana Gomez Lopez wrote this book in Italy, in Italian, the outcome of a long and fruitful period of study at the Department of Philosophy and the International Center for the History of Universities and Science at Bologna University. It is a stimulating and in several respects original study, extending our knowledge of the history of science in the era after Galileo. Instead of analyzing the thought of an individual writer or the activities of a single institution, she chose to carry out a meticulous reconstruction of a long and bitter philosophical and scientific polemic, from the end of the sixteen-sixties, between the two important figures of the book's title. They both thought of themselves as heirs to Galileo, faithfully carrying on his work; but in reality they inhabited two very different conceptual universes, and had diametrically opposite ideas on the aims and methods of scientific research.

Geminiano Montanari (1633-1687), professor of mathematics and astronomy first at Bologna and then Padua, stood for a rigorously experimentalistic and antimetaphysical approach to science, which he had arrived at by grafting some of Bacon's, Boyle's and Gassendi's ideas on to Galileo's. In Bologna he had founded the Accademia della Traccia- on the model of the Accademia del Cimento, and on that of the more recent Royal Society of London.

Donato Rossetti (1633-1688), was the pupil at Pisa of Giovanni Alfonso Borelli, and friend of Lorenzo Bellini and Alessandro Marchetti. He taught first logic and later philosophy at Pisa, belonging to that current of post-Galileans who argued that what was absolutely basic was research on the causes of phenomena and on the structure of matter. These philosophical interests led to Descartes, and to Gassendi the restorer of atomism, but above all to uniting physics and Galilean mechanics with the Renaissance visions of nature of Bruno, Campanella and Telesio.

What rendered these positions potentially dangerous, if propagated openly, were also the connections that could be made with the youthful Galileo's sympathies for atomism. Understandably, in the seventies the Pisan circle of Galileo's followers had to suffer the attacks of the peripatetic traditionalists, who later succeeded in having the teaching of atomist doctrine in the university of the Grand Duchy banned. Rossetti's open adherence to an animated vision of nature and of the Earth, and to a form of vitalistic atomism, if it was embarrassing for his friends, who were trying to gain acceptance for a moderate version of Democritus' philosophy compatible with Christianity, certainly hasn't gained him the sympathy of posterity. To the few scholars who have noticed him in passing, Rossetti has seemed backward-looking, an obscure and fanciful Renaissance philosopher, who despite his own claims, has nothing in common with Galileo or modern science. Why waste time therefore on the study of his works, almost all devoted to his polemic with Montanari, who both his contemporaries and posterity have seen as the perfect incarnation of the new science (mechanical, experimental, metaphysically neutral and socially useful)? Surely we already know, a priori, how to distinguish the new from the old, or reason from error.

Guided by her belief in the plurality of Galilean traditions, Susana Gomez believes that it is worthwhile examining the positions of both the contenders in the dispute with equal attention, placing them in the context of the Italian and European debates on the same subjects. In reality, her sympathies seem to lie with Rossetti. Of course she spends a long time on Montanari's experiments on the phenomenon of capillarity and on the glass drops, or Prince Rupert's drops, as well as on his epistemological considerations (which owed a lot to Boyle), on the problem of empty space and the structure of matter, exploring already available research on these subjects. But at the real heart of the book stands the surprising figure of Rossetti, and the exposition of the system of nature he worked out and made public in Antignome physico-matematiche (1667), where he violently attacked Montanari's Pensieri fisico-matematici published in the same year: matter is formed, through the will of God, of atoms qualitatively distinct, "light" and "dark", endowed with an intrinsic dynamic principle, and therefore capable of "passions", "sympathies" and "antagonisms"; the Earth is a living and sentient being, with a pulsating heart at its core, whose movements (interpreted in a modern way according to the model of Harvey) are capable of explaining all hydrogeological and meteorological phenomena. The Renaissance matrix of these theories is obvious, but they were only an extreme manifestation of a need for speculative research which had been removed in public debates for reasons of prudence. This need was very widely felt at the level of private discussion among the followers of Galileo, and it was felt also by Rossetti's master, the authoritative Borelli, so much so that some suspected him of being behind the polemic, manoeuvering behind the scenes. This applies not only for Montanari, who in his Pensieri had oddly not mentioned the fact that the experiments he had proposed had already been carried out by Borelli himself in the Accademia del Cimento, and so should have been aware of the irritation felt towards him; but it also went for Marcello Malpighi, whose relationship with the man who had introduced him at Pisa to the "free and Democritean philosophy" was increasingly in difficulties precisely because of their differences over the role and the function of the capillary vessels and in particular over the capillary structure of the lungs, suggested by Borelli, but anatomically demonstrated by the Bologna scholar. The latter accepted Montanari's explanation of the rise of liquids in the capillary vessels, founded on the interaction between air pressure and the viscosity of the liquids, caused by their corpuscular structure. Borelli in his De motionibus naturalibus a gravitate pendentibus (1667), had explained the phenomenon of capillarity by attributing it exclusively to the gravity of the fluids and excluding the idea that air pressure could play any kind of role. For him gravity was an intrinsic force of bodies, and in a letter to Malpighi of the same year he had said he believed that the particles of blood were driven to penetrate the alveolus of the lungs by a faculty appertaining to each one of them. His pupil Rossetti went further, attributing the rise of the liquids in the "capillary vessels" to the "appetite" of the atoms for the glass, the true physical cause of the "effects" described by Montanari in his experiments. Lopez suggests persuasively that it was in fact the publication of Rossetti's Antignome that was the real cause of the definitive break between Malpighi and Borelli, throwing new light on an episode which has always been shrouded in mystery.

From her perceptive and detailed analyses (also on other subjects, such as Rossetti's casting doubts on the postulates of Archimedean-Galilean statics, moved by the need to find a metaphysical foundation to the new laws of motion), Pisan and Bologna scholars are ranged on opposite sides in a profound split between second generation Galileans. The Pisans did not wish to surrender the practice of philosophical freedom in the widest sense, openly attacking the defenders of the peripatetic tradition and even some of Galileo's concepts. The Bologna group, faced with the academic and religious authorities, believed that giving up enquiry into causes and principles was the price to be paid to legitimate experimental enquiry on nature. Brutal ecclesiastical and political repression put a stop to the speculative research of the Pisans, while at Bologna and Padua Montanari's (and Malpighi's) pupils succeeded in getting the new experimental philosophy to penetrate the official institutions (universities and academies). By experimental philosophy they meant research on effects which was purely descriptive, and programmatically disinterested in their metaphysical causes. From this tradition, rather than from Borelli's, undoubtedly derived the distinctive features of eighteenth century Italian science, especially that carried on and taught in the official institutions (from Bologna to Padua and Pavia), on which there has been a good deal of research in recent years. The lack of interest in metaphysical questions has been seen as a limitation of the Italian scientific tradition, both by neo-idealist philosophers and more recently by the followers of a philosophical history of science. Whereas others have argued that the adoption of experimentalism created the necessary conditions for a quite timely reception of Newtonian physics, enabling Italian natural philosophers to remain within the more advanced circles of European science.

-Chronologically these questions are beyond the period examined by Susana Gomez, who obviously does not dwell on them. Her book does, however, help to illustrate the initial phases in the process of formation of modern Italian science. Not only because through Montanari she brings out the archeology of the epistemological and methodological model which won out, but still more because through Rossetti she reminds us that Galileo's work gave rise to very different trends, more concerned about the metaphysical foundations of the new science. The Renaissance categories and style adopted by some of them, especially Rossetti, to express these needs, does not mean that they were backward-looking. Rather, in Susana Lopez' opinion, if they are interpreted from a European perspective, they may be seen to be forerunners of orientations that in the eighteenth century will become widespread, not just among Leibniz' followers but also among those of Newton. If it is possible that this kind of opinion may partly be dictated by the author's natural tendency to defend someone who has been neglected until now, and who she has rediscovered and finally come to understand, her invitation to study the debates of the post-Galilean era with less prejudice, eliminating that attitude of contempt towards the positions of the "losing" side which we could call, paraphrasing Vico, "the arrogance of the victors", should be taken seriously.

Address: Marta Cavazza, Department of Philosophy, University of Bologna, via Zamboni 38, I-40126 Bologna. E-mail: