This contribution draws on work in political philosophy to reflect on the growing discourse about "commons" in science and civil society. In general, "commons" can be seen as contested (mostly through enclosure, under-/overuse or social dilemma) im/material resources, whose relevance for a group (e.g. humanity) justifies a demand for regulation, mostly described as a form of inclusive self-governance. Thus, it's not only about a specific governance of common-pool-resources in diverse property regimes, but touches fundamental questions of legitimate ownership, sovereignty, inclusion or democratic will-formation - just to name a few.
The paper explicates some of these inherent implicit and explicit normative assumptions found in the commons concept to then ask whether this helps to tackle wicked problems of sustainable global commons (GC) management, e.g. related to biodiversity, forests or atmosphere. In giving reference to a Habermasian approach on the possibilities of a "global public policy" in a post-national setting, it claims and justifies a politicization of global governance to develop notions of a transnational derivative legitimation.
The origins of this politicization are twofold. Firstly, there's a demand for regulation, meeting the prevalent absence of "global-internal-policy-institutions", or a "world state". At the same time the indisputable influence of existing global governance on domestic decisions generates a demand for legitimation, which hardly can be met via formal democratic procedures globally.
In using this approach the paper stresses the need for a discursive public struggle about the most justifiable rationalities and adequate procedures in dealing with GC-problems. Therefore the (re)emergence of political competency on the international level does neither rely exclusively on professional expertise or output orientation, nor only on abstract moral claims (like the one on initial ownership of natural resources), but also on the proper involvement of a global public sphere to shape the horizon of recognized justifications for global action.
