  But there was a difficulty inherent in Jacobi’s proposed theory. It came out most poignantly in the third part of the Dialogue — a part dedicated, for the most part, to an exposition of Leibniz’s metaphysics (Jacobi, 1787: 144ff). Here Jacobi portrays the German Leibniz as the champion of individuality, and also tries to show how it is possible to accept his Monadology if duly modified. The transition in the Dialogue between second and third part is performed rhetorically. There was, however, a conceptual basis for it. And it was in this, in the obvious logical connection between Jacobi’s just suggested theory of experience and Leibniz’s Monadology, that the difficulty lay. For the organic conception of rationality that that theory implied — reason being nothing more than a more developed, more reflective, form of sensibility — fitted well indeed with Leibniz’s system. But it also clearly led to Leibnizian naturalism. And the idea that the ‘self’ cannot be defined except in terms of an ‘other’, while also well fitted to the Monadology, also led to the equally Leibnizian position that everything in the universe is itself by reflecting everything else. Jacobi had however made his philosophical debut precisely by combating the assumption that everything can be explained by reference to everything else — a position that he thought reflected the philosophers’ logical enthusiasm for explanation and which he opposed because it ended up undermining human subjectivity.