This article explores the role of constitutional thought in Latour’s work on cosmopolitics. It will study his non-modern proposal in the Politics of Nature (2004) and argue for a constitutional rather than political understanding. To address criticisms of being too metaphysical or unpractical, we will work out the notion of a “constitutional ecology of practices” to highlight how different practices such as politics, science, organization, but also law, all contribute to the design of the stage and processes for composing a common world. Special focus will here be placed on the role of “epigrams”: practical models for ordering contributions of different practices or modes in hierarchical relationships. This renders them identifiable, mobilizable, and contestable as cross-cutting models for shaping mutual relations in concrete collaborative settings. The case of the legal regulation of robots will be presented as an example of a cosmopolitical attempt to introduce non-human entities in the common collective. We will here observe the role that epigrams play in framing, ordering and contesting the epistemic contributions of the various practices involved in this innovation ecology. This case will be used to discuss Latour’s proposals and to study non-modern constitutionalism in action.