This chapter concludes the detailed analysis of Le Monde, begun in the previous two chapters. It has three main goals: Firstly, Le Monde is examined as a competitive bid for supremacy in the natural philosophical field. This is done by viewing it in relation to key natural philosophical aspirations and strategies of similar contemporary actors, such as Kepler, who, like Descartes, were attempting to displace Aristotelianism, install some version of realist Copernicanism, and create alternative hegemonic natural philosophical syntheses. Secondly, Le Monde is assessed in terms of its strengths and weaknesses as a system of natural philosophy, using the model of natural philosophical systematicity developed in  Chap. 2. Finally, examination of the systematicity of Le Monde leads to some striking individual examples of refinements in that regard, as displayed by the Principia philosophiae to come.