In this paper, I argue that stance voluntarism is a coherent and useful view for understanding debates about the ontological commitments warranted by science. To do so, I first engage in a defensive move: I rescue stance voluntarism from what I take to be the most pressing objection to have emerged in recent literature, which I call the ‘irrationality objection’. According to this objection, an agent courts irrationality by simultaneously holding an epistemic stance and believing that stance voluntarism is true. (...) I argue that this objection is based on a misunderstanding of stance voluntarism and the kinds of reasons that agents take themselves to have for their adopted stances. I then make the positive contention that we can expect the idea of stance voluntarism, thus saved, to not only be a defensible, but also a useful framework for understanding ontological disputes within science. I do this by presenting a case study from contemporary cosmology in which it is so. Combining these two claims, I argue that stance voluntarism is a coherent and useful view for understanding some ongoing disputes about ontology within scientific contexts. (shrink)