Stance voluntarism highlights the role of the will in epistemic agency, claiming that agents can control the epistemic stances they assume in forming beliefs. It claims that radical belief changes are not compelled by the evidence; they are rationally permitted choices about which epistemic stances to adopt. However, terms like “will”, “choice”, and “stance” play a crucial role while being left as vague notions. This paper investigates what kind of control rational agents can have over epistemic stances. I argue that (...) whether epistemic stances are voluntary depends on what kind of stance is being assessed. Sometimes epistemic stances are taken to be evaluative attitudes about how to produce knowledge. This kind of stance is not directly controllable, since it is essentially connected to beliefs, and believing is not voluntary. But sometimes epistemic stances are taken to be styles of reasoning and modes of engagement, expressing ways of approaching the world in order to produce knowledge, which can be voluntary. Overall, this supports a formulation of stance voluntarism as a dual-systems theory of epistemic agency, where epistemic rationality is compounded by a dynamic interplay between involuntary processes of belief formation and voluntary processes of cognitive guidance. (shrink)