The Principle of Sufficient Reason in Early Modern Philosophy of Science: Leibniz, Du Châtelet, and Euler

I distinsuish three ways in which early modern rationalists seek to apply the principle to empirical science. Previous readings have neglected how these thinkers assume substantive theories of explanation and intelligibility in many of their deployments of this rationalist principle. I argue that Leibniz, Du Châtelet, and Euler are all vulnerable to the objection that they deploy their standards of intelligibility inconsistently: their own favored explanations do not always live up to the standard. This chapter also defends more particular interpretive claims about these thinkers, for example arguing against Jeff McDonough’s anti-realist reading of Leibniz on laws of nature.