Machines and diseases: Giorgio Baglivi and his mechanistic physiopathology

The Croatian physician Giorgio Baglivi (1668-1707), professor of anatomy and surgery and, from 1702, of theoretical medicine at the Studium Urbis, is traditionally considered a leading representative of the Italian “iatromechanism”. Iatromechanism (or iatrophysics) is a 17th-century medical tradition, which attempts to explain normal and diseased states of the body in mechanistic terms, according to the laws of physics. In a famous passage from De praxi medica, quoted by Canguilhem in Machine et organisme, Baglivi compares the parts of the body to different kinds of physical devices, such as retorts, hydraulic pipes, springs, ropes, and so on. However, despite this radical reductionism, Baglivi also realizes that diseases cannot be entirely reduced to physics, the morbid states of the body being something completely different from malfunctioning of machines. Baglivi in fact rejects the use of mechanical devices for the treatment of diseases; in his view, the improvement of medicine only depends on the practice itself. Therefore, Baglivi recognizes, albeit not explicitly, the limits of iatromechanism in pathology, proving that this category needs a thorough revision. In this paper, I examine the role of mechanics in Baglivi’s medicine, by analysing, in particular, the problem of the relationship between solids and fluids in the body.