General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Science suggests a thought-provoking reorientation of the social sciences. Addressing some of the key assumptions in Wendt's account, this article argues that despite a quite elaborate and eloquent development of a monist ontological position, conceptual discussions remain solely focussed on the nature of beings and neglect wider implications for the nature of being, particularly human being, that arise out of its abandonment of a substance ontology. To develop such a critique, I will first address some preliminary considerations about the broader assumptions underlying Wendt's argument. Secondly, the article zooms in on the central concern arising out of Wendt's approach regarding the conceptualisation of human being before raising a set of critical remarks which need further deliberation if a quantum approach to the social sciences is to be successful.Keywords: ontology, consciousness, reflexivity, ontological difference Big leaps in the conceptualisation and understanding of IR are rare. We can list seminal contributions (mostly only recognised retrospectively as such) at critical junctures within the discipline but overall these 'revolutionary', rather than 'evolutionary', contributions are few and far between. Additionally, even those often seen as 'revolutionary' in their contribution to the study of international relations are not unanimously recognised as such, not least due to the growing and accelerating diversification of (meta-)theoretical positions within IR. 1 In many ways, Wendt's contribution arrives at a time when meta-theoretical debates are back on the agenda within the discipline of IR. 2 Of course, matters concerning fundamental 1 Peter Marcus Kristensen, 'Discipline admonished: On International Relations fragmentations and the disciplinary politics of stock taking