Abstract
In this paper it is argued that the _Physical Monadology of 1756 has to be seen as an attempt to evade the same paradox as the one given in the second antinomy of the _Critique of Pure Reason. Since this attempt presupposes the claim that space rests upon relations between substances, it contradicts the thesis that it is a mere form of intuition, presented by Kant in his dissertation of 1770. Therefore, at least since 1770 the paradox of the divisibility of matter rose up again so that Kant had to deal with it once again in his first _Critique. Remarkably, his key to solve the second antinomy is the same which ruled out his earlier solution of 1756 and gave rise to the paradox again, i.e., the ideality of space and time. But, contrary to the dissertation, in the _Critique it is substituted by the doctrine that our knowledge of objects depends on and is restricted to intuitively given objects and this is crucial to the solution of the second antinomy. Finally, it will be shown how Kant deals with the problem of the divisibility of matter in the _Metaphysical Foundations of Natural Science