Dilemma and Opportunity: The Physiology of the Soul

Dilemma and Opportunity: The Physiology of the Soul KATHLEEN WELLMAN W hen eighteenth-century physiologists set out the fundamental principles for their studies of the human body, they began, quite unexpectedly for the modern reader, with the soul. Their exploration of the soul was not formulaic, an atavistic invocation of tradition, or even simply a nod toward orthodoxy. Instead, in the physiological texts I propose to discuss , written between 1674 and 1753, discussions of the soul were both central to the text and, I would contend, crucial to the development of the French Enlightenment. The pre-eminent role of the soul in physiology was long standing. As historians of physiology have noted, most crucial questions of physiology derived from the Greeks, including the issue of the soul or psyche. For example, a significant early formulation of this theme was Aristotle's definition, "the soul, therefore, is the primary act of a physical body capable of life."1 Although prominent in Greek philosophy and still influential in the Middle Ages, the soul, in the course of the early modern period, was gradually assigned a less significant role in describing physiological functions. Histories of physiology suggest that as the mechanical philosophy became more influential, questions of the soul were progressively excluded until a vitalistic reaction was provoked.2 Thus a return to a traditional theme in the late seventeenth and early eighteenth century might be thought to be simply a reaction against 301 302 / WELLMAN mechanism or an early vitalist revival. Furthermore, it might well be assumed that such a traditional theme impeded eighteenth-century physiological speculations. My intent, however, is to suggest that discussion of the soul afforded particular opportunities for physiologists to effectively expand their area of inquiry. They did not use the soul because they were opposed to mechanism,3 but rather because it afforded them fruitful ways to discuss physiological functions. And discussions of the soul also led physiologists to treat philosophical and theological issues in new and radical ways that were subsequently useful to the philosophes. The question of the soul was so prominent in the early eighteenth century in part because physiologists set their works explicitly within the parameters of philosophical debates.4 This philosophical concern can be explained in part by the very nature of physiology in the eighteenth century—biological sciences were divided into physiology and natural history.5 Natural history, based in part on a system of Baconian classification and considered as a function of memory on the encyclopedic tree of knowledge, used natural phenomena to oppose the aridity of mechanism and to demonstrate the glory of God.6 Physiology, however, was a different kind of discipline. Classified as a part of physics, its place on the encyclopedic tree of knowledge was under reason, its realm was the investigation of function, and its practitioners were inclined to place their investigations within a philosophical context. Several factors contributed to the affinity between philosophy and physiology: physiologists of the period were almost invariably physicians well trained in Aristotelianism7 ; they pursued or were fully aware of investigations of brain physiology; and their investigations inevitably challenged metaphysical assumptions which could not be empirically demonstrated. The Physiology of the Soul In physiological texts written in France from 1688 to 1753, a number of medical practitioners, for example, Guillaume Lamy, François Maubec, Antoine Louis, Louis Moreau de St. Elier, and Antoine Le Camus8 investigated the physiological bases of human behavior by treating the physiology of the soul. Although these works were written over a period of about seventy years, and despite the fact that their authors belong to no particular physiological or philosophical school, they all nonetheless reflect great interest in the physiology of the soul and an awareness of the problems and opportunities discussion of this issue afforded them. These physiologists considered the soul such a central issue that they addressed either an entire text or an extensive section of Physiology of the Soul / 303 their texts to it. For all of them, it was fundamental to define at the outset their positions on the question of what the soul is, where it resides, and how it interacts with a body. They also sought to describe the...