(b. Florence, Italy, 3 September 1643; d. Florence, 8 January 1704)
physiology, medical theory.
Bellini, born to a family of small businessmen, benefited from the patronage of Duke Ferdinand II of Tuscany from his early youth. Under the duke’s protection, he attended the University of Pisa, where he studied philosophy and mathematics with some of Italy’s leading scientists, most notably Giovanni Alfonso Borelli. At the precocious age of twenty, Bellini was appointed professor of theoretical medicine at Pisa, and with Duke Ferdinand’s assistance he acquired a chair of anatomy five years later. He resigned the chair when he was about fifty, to become first physician to Duke Cosimo III of Tuscany.
Considered a founder of Italian iatromechanism, Bellini was a pioneer in applying mechanical philosophy to the explanation of the functions of the human body. His earliest interests were anatomy and physiology. The first essay he published, Exercitatio anatomica de usu renum (1662), was an important study of the structure and function of the kidneys. Until Bellini’s time, the kidneys were widely understood in terms laid down by Galen. Said to be composed of a dense, undifferentiated “parenchymatous” material, they were thought to form urine through the exercise of special “faculty” that controlled the selective secretion of urine from the mass of the incurrent blood. But under the influence of the mechanical philosophy he learned from Borelli, Bellini rejected this Galenic theory as absurd. He sought a less verbal and more mechanical explanation, and when he reexamined renal anatomy in this frame of mind, he discovered in the supposedly unorganized parenchyma a complicated structure composed of fibers, open spaces, and densely packed tubules opening into the pelvis of the kidney. This unsuspected structure provided the key to true renal function.
Bellini posited that arterial blood brought into the kidneys is separated into urinous and sanguineous portions by a sievelike arrangement in the renal vessels and fibers; the urinous portion collected in the urinary tubules and the blood returned to the circulatory stream through the venules. He meant this mechanical explanation of urinary secretion, achieved by the “configuration alone” of the renal vessels, as a general substitute for Galen’s incomprehensible “faculties.”
Bellini’s mechanical manner of physiological explanation won the admiration of contemporary scientists in Italy and abroad, and his anatomical discoveries were considered worthy enough in themselves to merit careful scrutiny by, among others, Marcello Malpighi. Nevertheless, after his initial triumph Bellini’s direct interest in anatomy and physiology slackened. In 1665 he published an essay on taste, Gustus organum, which included sections on the functional anatomy of the tongue. The intention of this work, however, was mainly to account for the general phenomena of gustatory sensation according to corpuscular principles. For years afterward, Bellini published no other serious anatomical work, although he did maintain active friendships with Francesco Redi and, after 1676, with Malpighi. He kept abreast of scientific developments through his contracts and correspondence, and in 1683 he returned to print with De urinis et pulsibus et missione sanguinis, the first important attempt by an Italian systematically to apply the mechanical philosophy to medical theory.
In De urinis, Bellini seems to have been inspired by two earlier authors: the English physician and corpuscular philosopher Thomas Willis, whose medical works were published on the Continent in the early 1680’s, and Bellini’s old mentor Borelli, whose De motu animalium appeared posthumously in 1680. Both Willis and Borelli had tried, to some extent, to apply the mechanical philosophy to medical theory. Willis in particular had attempted to formulate corpuscular hypotheses, both to account for disease phenomena and to justify such traditional therapeutic methods as bleeding, purging, and vomiting. Bellini sympathized with Willis’ intentions but felt that he had introduced too many unnecessary and ad hoc assumptions. Willis supposed, for example, that a “fermentation” of the blood’s constituent particles was required to explain such diseases as fevers. By contrast, Bellini, under Borelli’s influence, preferred to think of the blood as a physical fluid with such simple mechanical and mathematicizable attributes as density, viscosity, and momentum. He postulated that health consisted in a well-ordered circulation and that disease implied some sort of circulatory imbalance or inefficiency. Thus, to arrive at the proper theory for a particular disease, one needed merely to set out the pathological phenomena and then to deduce them as consequences of an increased or diminished velocity of the blood. In this manner, Bellini thought, one could get beyond Willis’ tentative hypotheses to the real and “necessary” mechanical causes of fevers. He therefore substituted a hydraulic iatromechanism for a corpuscular one.
First reactions to Bellini’s hydraulic iatromechanism were uncertain. A few scattered admirers, such as Bohn in Germany and Baglivi in Italy, communicated their enthusiasm, but otherwise the De urinis seems to have made little real impact. Bellini turned seriously to medical practice, and in his letters he consoled Malpighi with the news that he too had many enemies and critics. But in 1692 Bellini’s affairs took a dramatic turn for the better. The Scots mathematician and physician Archibald Pitcairne, then lecturer on theoretical medicine at Leiden, wrote to express his admiration. Pitcairne was then trying to construct a mathematical and “Newtonian” medical theory, and he saw in Bellini’s work an example of the “methods of the Geometers” applied to medical problems. Pitcairne praised Bellini’s general theory of disease and urged him to develop further some of the ideas contained only in compressed form in the De urinis.
Bellini reacted favorably to Pitcairne’s encouragement; and he devoted the next few years to his last set of essays, which he dedicated to Pitcairne and published in 1695 as Opuscula aliquot. The Opuscula developed Bellini’s earlier iatromechanical themes most fully. Organized into postulates, theorems, and corollaries, it treats problems ranging from the hydraulics of intrauterine and extrauterine circulation to the mechanics of the “contractile villi.” For example, he considered the blood to be a fluid flowing through conical vessels, according to Borelli’s laws of hydraulics, and he imagined that the “contractile villi”(which explain the body’s reaction to stimuli) expand, contract, and vibrate like ordinary musical strings. In these carefully stated propositions Bellini hoped to explain all important physiological phenomena according to the laws of mechanics.
By the time the Opuscula was published, Bellini had already begun to enjoy an international reputation, largely through the influence of Pitcairne. During the early decades of the eighteenth century that reputation spread. Hermann Boerhaave, the most influential medical teacher of the time, studied with Pitcairne at Leiden and absorbed his enthusiasm for Bellini’s medical science. In England, too, Bellini’s theories enjoyed a considerable vogue from 1710 to 1730, when such physicians as George Cheyne and Richard Mead tried to build a “Newtonian” theory of the “animal oeconomy” and turned appreciatively to Bellini’s writings. His influence was somewhat tempered in Italy by the Hippocratic revival encouraged by Giorgio Baglivi, who had once been Bellini’s ardent admirer. Nevertheless, Bellini remained a major scientific authority until the mid-eighteenth century, when a general reaction to iatromechanism, in all its forms, set in.
1. Original Works. Bellini’s total scientific production was collected in a handsome posthumous edition, 2 vols. (Venice, 1732). Correspondence between Bellini and Malpighi has been edited by Gaetano Atti as Notizie edite ed inedite della vita e della opere di Marcello Malpighi e di Lorenzo Bellini (Bologna, 1847).
His individual works include Exercitatio anatomica de usu renum (Florence, 1662); De urinis et pulsibus et missione sanguinis (Bologna, 1683); and Opuscula aliquot (Leiden, 1695).
II. Secondary Literature. There is no full-length study of Bellini. A useful short biography can be found in Dizionario biografico degli italiani, VII (Rome, 1965), 713–716. Augusto Botto-Micco’s account in Rivista di storia delle scienze mediche e naturale, 12 (1930), 38–49, is also helpful. Charles Daremberg presents a summary of some of Bellini’s theories, along with a general account of the medical environment of the late seventeenth and early eighteenth centuries, in Histoire des sciences médicales, II (Paris, 1870), esp. 765–783. Useful information on Bellini’s career, particularly on his connections with Malpighi, can be found throughout Howard Adelmann’s mammoth Marcello Malpighi and the Evolution of Embryology, 5 vols. (Ithaca, N.Y., 1966).
Theodore M. Brown