This chapter summarizes section II of Immanuel Kant's dynamic conception of matter in the Metaphysical Foundations of Natural Science. It also summarizes Schelling's metaphysical construction of matter in the Ideas, which represents Schelling's initial thoughts on the concept of life. In the transcendental doctrine of method, Kant distinguishes philosophical cognition, which is rational cognition from concepts, from mathematical cognition, which follows from the construction of concepts. According to Kant, the Cartesian mathematical-mechanical mode of explanation seeks to explain all the properties and actions of matter by its purely geometrical properties. If Schelling's solution in the First Outline subdued his much stronger dogmatic claims in the Ideas and the World-Soul, it brought forth a new problem, namely, the conception of science as a body of knowledge not grounded on self-evident and absolutely necessary principles.