Union and Interaction of Body and Soul

Notes and Discussions REPLIES TO DAISIE RADNER'S "IS THERE A PROBLEM OF CARTESIAN INTERACTION?"* 1. UNION AND INTERACTION OF BODY AND SOUL 1 By the end of the Meditations, having reinstated the existence of corporeal objects, Descartes acknowledged that his distinction between body and soul threatened to render incoherent the notion of a person as a unified creature which is the subject of sensations and appetites. Thus, he insisted that it was insufficient to suppose the soul is lodged in the body "like a pilot in a ship," and that such a conception did violence to the concept of a person, making it impossible to understand the nature of the passions. Those following Descartes saw even more severe problems deriving from Cartesian dualism; for the essential difference between body and soul appeared to rule out altogether the very possibility of interaction between the two. This included not only Cartesians such as R6gius and Arnauld, but other philosophers no less eminent than Spinoza, Leibniz, and Malebranche. Indeed, the apparent incoherence of maintaining at once the essential difference of body and soul together with their interaction in perception and action has served as a touchstone in post-Cartesian discussions of the nature of body and soul. It has seemed apparent to many that Descartes' own attempts to handle the problem, most notably in his correspondence with Elizabeth and The Passions of the Soul, were virtually unqualified failures. They amounted, it seemed, to either an insistence on the fact of interaction, which few were disposed to doubt, or an appeal to the "union" of body and soul which *Journalof theHistoryofPhilosophy~3:l (1985): 35-49. I am thankful for discussions with A. Donagan, D. Gustafson, and W. E. Morris, which were helpful in formulating the ideas here. Comments from a referee for thisjournal were also extremely useful. [221] 222 JOURNAL OF THE HISTORY OF PHILOSOPHY manifestly presupposed the interaction of body and soul and so could not explain its possibility. ~ As Daisie Radner points out, insisting on the fact of interaction is no help, because the question is not whether there is interaction but whether the Cartesian philosophy can render it coherent; moreover , as she points out, if the possibility of mind-body interaction is explained in terms "of the nature of the union of mind and body, then Descartes has no solution. ''~ Despite the fact that emphasis on the problem of interaction between body and soul has a place of honor in traditional discussions, no less than in contemporary commentaries, I have argued in "The 'Scandal' of Cartesian Interactionism TM that the difficulty is apparent only and that the force of Descartes' responses to it has been misunderstood and underestimated. First, there is no difficulty with mind-body interaction internal to the Cartesian philosophy. Descartes assumes simply that there are two fundamentally different forms of causal interaction. Causation in the case of interaction between bodies is a function of extension. Interaction between mind and body is not. Second, there is no logical incoherence in such a position. A multiplicity of forces is no less coherent than a single force in nature. To posit such a multiplicity may be less parsimonious, but to admit that is hardly to admit that there is a serious principled or logical objection to Cartesianism. Third, the task of explaining the unity of the person, and understanding the passions, is the task which engages Descartes in his discussions of the "union of body and soul." The nature of this union, he claims, can explain the appearance of there being a problem with interaction of body and soul. 5 It is nonetheless a wholly distinct problem. Fourth, the crucial notion to be understood in understanding his doctrine of the union of body and soul is that of a "substantial union" and, correlatively, that of sensations as "modes of a thinking substance." The person is a substantial union in being a composite entity with attributes which are attributes only of the composite and of neither of the elements alone. That l am by no means disposed to deny or doubt that some did cometo doubt that there was interaction between body and soul. The occasionalismof Malebranche, as wellas the...