In February 1689 Gottfried Wilhelm von Leibniz (1646–1716) published
the Tentamen de motuum coelestium causis in Acta Eruditorum. This work deals
with a planetary model. This essay is not a mere formal–or–virtuosic mathematical
exercise only. It represents a significant conceptualization within a general physical
theory that Leibniz was going to construct. It is well known that Leibniz rejected the
action at a distance. He was convinced that each interaction between bodies should
be explained by means of mechanical causes only. However, we remark: 1) he was a
contemporary of Huygens and Newton and – obviously – he had to take into account
Newton’s results; 2) he thought that also the final causes should play a role in the
physical explanations. In fact, his introduction of the vis viva is connected to the
idea that the final causes could play a role within physics. This fact offers an
interesting and stimulating picture, which has fertile consequences both in his
planetary model and in the role played by planetary model in his entire theoretical
system. In order to inquiry historically and philosophically Leibniz’s planetary
model, we introduce the epistemological key–notion of the physical–structural
model. This is connected with Leibniz’s attempt of edifying a physical system:
observation, physical quantities and mathematical interpretations are involved in
such model. Within this context both the effects of the most important actions
(specifically gravity) and physical causes were dealt with by Leibniz. In this paper,
we present and discuss, by means of the above key–concept, Leibniz’s planetary
model. This paper is part of a larger research programme (RP) concerning the
relationship between physics and mathematics in the history and philosophy of
science.
