What Kind of Idealist Was Leibniz ?

Since the publication of Montgomery Furth’s groundbreaking 1967 essay, ‘Monadology’, discussions of Leibniz’s phenomenalism have been one of the main staples of Anglo-American Leibniz-scholarship. By no means, however, has any consensus been reached with regard to this issue. I think one important reason for this failure in agreement has to do with how one goes about understanding a related concern in Leibniz: namely, Leibniz’s idealism. In the present essay, I propose to interpret Leibniz’s idealism in contrast to two extreme versions of idealism. What I would like to suggest is that Leibniz promoted arguments in favour of a kind of idealism that may be described as ‘conceptual’, but wound up with an unusual brand of idealism that may be considered neither conceptual nor phenomenal. Another reason for the failure in consensus is a perceived incompatibility between Leibniz’s phenomenalism and his aggregatum-theory of corporeal substances. I will deal with this perceived incompatibility in Section II by emphasizing Leibniz’s epistemological account of how what he calls ‘clear but confused perceptions’ may be resolved into distinct perceptions. In Section III, I will pursue a conceptualist interpretation of Leibniz’s idealism with recourse to his conception of unity. In Section IV, I will examine the limits of the conceptual idealist approach.