Abstract

Kant developed his protophysics mainly during his precritical period. His first presentation of it is found in Thoughts on the True Estimation of Living Forces. However, the most important work of his protophysics is Physical monadology. Physical monadology is a conception that is more closely connected with dogmatic than with critical metaphysics. His principal adversaries here are Newton and Leibniz. Physical monadology is an immediate link between his early critical conception and his later critical ideas. The culmination of his protophysical inquiries is his habilitation dissertation, which is an attempt to reconstruct this system concisely.Insofar as they were necessary for his alternative system, Kant considered problems that had not been taken up by his predecessors. For example, in his Meditations of fire he tried to point out what the ether was, something which Newton had not considered, while in his Thoughts on the True Estimation of Living Forces he attempted to establish a law for measuring living forces, which Leibniz, in turn, had not taken up. Defining the notion of ether made it possible to decide whether matter was punctual or not and to establish the nature of the mutual influence of the material elements. This notion was thus crucial for organizing the system. Furthermore, his attempt to establish the law governing the living forces was, in turn, intended to put in order the whole domain of activity in the world and was necessary to ground the principles of mechanics, dynamics, kinematics, etc.The final attempt to overcome the conceptions of his predecessors was the creation of his own project of a new physics, the first part of which was the Physical monadology.