Niccolò Fioravanti

This paper explores the metaphysical significance of Leibniz’s conception of elasticity and its development during the 1680s. The first part is devoted to the discussion of elasticity as a system property in the Hypothesis physica nova of 1671. A second section shows the transition, in the second half of the 1670s, from such a conception to an understanding of elasticity as a condition for the spontaneity and individuality of bodies. Finally, through an examination of writings from the 1680s about the transmission of sound and the elastic properties of materials, I will reconstruct the underlying metaphysical framework characterizing Leibniz’s conception of elastic matter, namely the idea of a “mechanical mirroring” which is proper to individual bodies.

Cet article analyse la conception leibnizienne de l’élasticité comme principe structurel de la matière et son rôle dans le développement d’une métaphysique des substances corporelles. Il se concentre spécifiquement sur la fonction de l’élasticité comme condition nécessaire d’inhérence et de distribution de la force dans les corps vivants et comme réquisit structurel d’organisation physiologique. Cette fonction sert à actualiser la notion leibnizienne de mouvement naturel perpétuel, caractérisant l’économie interne des forces dans les êtres vivants. Le recours à l’élasticité pour incarner ce point de vue indique l’émergence d’une métaphysique des corps véritables, relevant de substances corporelles et conçus comme des structures requérant la coopération d’autres substances pour réaliser la distribution des forces.

This paper examines the development of Leibniz’s conception of elasticity in the framework of his theory of force and its connection with the individuality of bodies. The main aim of the paper is to show how elasticity, according to Leibniz, constitutes the main conceptual device that allows one to conceive bodies as structures and also a necessary (albeit not sufficient) feature of what he considers to be real bodies. To do so, I firstly discuss Leibniz’s subdivision of forces into “dead”, “living”, “respective”, and “directive”, and their “economy” within bodies. Secondly, I address the problem of the conversion of living force into dead force and vice versa and show how the “economy of forces” is grounded in Leibniz’s conception of elasticity as a structural property of matter. I conclude by examining how the function of elasticity leads to a structural conception of bodies and by evaluating its metaphysical consequences.