Conflicts of the soul and mind-body interaction in Descartes’s "Passions of the Soul"

In the following paper, I aim to provide a clear account of Descartes’s explanation of akratic behaviour in his “Passions of the Soul”. The analysis of Descartes’s arguments will give me the occasion to remark on some aspects, which I regard as seminal for the understanding of his controversial theory of mind-body interaction through the pineal gland. In particular, I will focus on Descartes’s insights into his theory of the “Natural Institution” and the role of the body as the effective place where the “conflicts of the soul” are determined to occur. To begin my exposition, in the first section I will briefly recall the Platonic theory of the partitioning of the soul, presenting it—in agreement with a long interpretive tradition—as Plato’s answer to the philosophical problem of akratic behaviour. In the second section, I will introduce Descartes’s arguments in favour of the unity of the soul, and identify their possible polemical targets. In the third section, I will analyse Descartes’s treatment of the notion of “conflicts of the soul” and his characterisation of the role of the body in determining the origin of these conflicts. In the fourth section, I will analyse Descartes’s account of mind-body interaction, focusing on the autonomy of the body, its union with the soul, and the activity of the soul. I will complete this analysis, in the fifth section, by considering Descartes’s remarks on the “natural institution” of a correspondence between psychological and physiological states. These considerations will clarify Descartes’s references to an indirect activity of the mind upon the body, and of the body upon the mind, and will help understand the means by which Descartes maintains the existence of akratic behaviour and the unity of the soul at the one and the same time.