  The seventeenth and early eighteenth centuries saw the heyday of metaphysical system-building, but the expression “continental rationalism” primarily connotes rather a set of epistemological views. By contrast to British empiricism, which traces all knowledge to sensory experience, these views emphasize a reliance on reason (ratio in Latin, hence rationalism), the resources of which are taken to be sufficient in some sense for what we know. Thus, a signature doctrine of rationalism is the doctrine of innate ideas, according to which the mind has built into it not just the structure of knowledge but even its content. Nonetheless, among the philosophers comprising the extension of the expression, metaphysical issues, particularly the ontology of substance, occupy the central place. Certainly, this is true of Leibniz and Spinoza, but also of Malebranche and other Cartesians, and even of Descartes on some plausible understandings of him.