In this paper, I attempt to reconstruct Schelling’s theory of organism, primarily as it is elaborated in the First Outline of a System of the Philosophy of Nature and the Introduction to the Outline. First, I discuss the challenge that the properties of organisms presented to the dominant scientific viewpoint by the end of the eighteenth century. I present different responses to this challenge, including reductive materialism, metaphysical and heuristic vitalism, and the Kantian response, and I situate Schelling’s account of (...) organism with respect to these responses. I argue that while Schelling agrees with vitalism in that he wants to preserve the specificity of organic phenomena, he rejects principles such as vital forces or the formative drive postulated by vitalism, even for purely heuristic purposes. I argue that Schelling understands organisms fundamentally in terms of the coordinated functioning of their organs. I further clarify Schelling’s account of problematic organic phenomena by focusing on his treatment of the relation between organic activity and organic receptivity. For Schelling, organic activity and organic receptivity mutually condition each other. I provide a detailed account of how this is supposed to work. (shrink)