The Problem of Unconscious Perception in the Early Enlightenment: The Case of David-Renaud Boullier

Abstract

or early modern readers, Descartes's views on animals were both scandalous and fascinating. His intriguing description of animals in terms of mechanism, coupled with the denial of any immaterial principle operating behind their observable behavior, prompted various critical reactions, which from the second half of the eventeenth century tended to focus on the problem of unconscious perception. On the Cartesian view, human cognition is accompanied by reflective consciousness, and clearly belongs to immaterial beings, whereas bodily interactions rely on mechanical principles. The challenge leveled against this dichotomy attempted to point out that certain mental states are both essential to the animal and irreducible to either bare mechanism or conscious mental operations. What this objection suggests is that between the uncontroversial cases at the two extremes there exists an intermediate realm, a gray zone of cognition as it were where an immaterial agent performs unconscious operations. Such a middle ground is crucial for understanding animal life, for it allows the proponents of the anti-Cartesian case to argue that although animals are incapable of reflexive thought (and for this reason cannot aspire to the highest privilege of immortality) they transcend the limits of pure mechanism. In this manner, unconscious, or not fully conscious, perceptions provide a model for animal cognition. This area of uncertainty between higher cognition and lower mechanism plays a prominent role in David-Renaud Boullier's (1699-1753) Essai philosophique sur l'âme des bêtes. As this book, first published in two volumes in 1728, is the most elaborate early eighteenth-century study of the animal soul, it