The eighteenth-century German rationalist tradition is, broadly speaking, committed to (what I call) ‘the principle of rational cognition’: the grounded must be rationally cognizable from its sufficient ground. Whereas the prevailing view takes the fundamental challenge to rationalist paradise to stem from the principle of sufficient reason, I argue that it instead stems from this principle: How is it possible to rationally cognize anything at all from its ground? By investigating the opposing responses of two of Leibniz’s most influential immediate (...) successors, Christian Wolff and Christian Crusius, we find no easy way to remain in rationalist paradise. (shrink)

Christian Wolff, long regarded as a champion of dogmatic rationalism, was in fact deeply involved in empirical sciences such as physics, astronomy, meteorology, and agronomy. He also devoted a significant part of both his research and teaching to the life sciences and was especially eager to establish the theoretical foundations of medical practice. Challenging the scholarly cliché of Wolff ’s methodical apriorism, recent research has highlighted an empirical, a posteriori, or even experimental component of Wolffian science. This paper aims to (...) provide a different insight into.. (shrink)

This paper argues that Wolff’s rejection of Leibnizian monads is rooted in a disagreement concerning the general notion of substance. Briefly, whereas Leibniz defines substance in terms of activity, Wolff retains a broadly scholastic and Cartesian conception of substance as that which per se subsists and sustains accidents. One consequence of this difference is that it leads Wolff to interpret Leibniz’s concept of a constantly striving force as denoting a feature of substance separate from its static powers, and not as (...) their replacement. For Wolff, powers are essential possibilities of acting in subjects suited for independent existence. Force is a further ingredient that provides a reason for the contingent operation of powers. Unlike Leibniz, Wolff conceives force narrowly as a principle of actuality, which he calls the “nature” of substance, as distinct from its principle of possibility, or essence. (shrink)