This article aims to highlight the difficulties encountered by the experimental psychology promoted by Ribot, at the end of the nineteenth century up until the beginning of the twentieth century, with regard to the question of free will as part of his analysis of voluntary attention. It also aims to shed some light on William James’s possible role in Ribot’s subtle change of opinion in regards to the power of attention, as a mental effort somehow revealing the possibility of a top-down voluntary activity. In most of Ribot’s work, at first glance, the will is understood as a determined product of our idiosyncratic character, of our affective and physiological tendencies—rather than as an autonomous faculty of self-determination. But what might look like Ribot's commitment to determinism calls for some nuance. Some uses of the term "voluntary" in his work, particularly to describe the phenomenon of attention, seem to refer to a form of free will looking a lot more like an autonomous faculty than like a mere illusion induced by an epiphenomenal conscious state. We end the paper with remarks about the current state of studies of consciousness and voluntary action in relation to Ribot and James’s accounts of attention and will.