a1 Brock University
In Leibniz: Perception, Apperception, and Thought, Robert McRae alleges a flat “contradiction” (McRae 1976, p. 30) at the heart of Leibniz's doctrine of three grades of monads: bare entelechies characterized by perception; animal souls capable both of perception and of sensation; and rational souls, minds or spirits endowed not only with capacities for perception and sensation but also with consciousness of self or what Leibniz calls (introducing a new term of art into the vocabulary of philosophy) “apperception.” Apperception is a necessary condition of those distinctively human mental processes associated with understanding and with reason. Insofar as it is also a sufficient condition of rationality, it is not ascribable to animals. But apperception is a necessary condition of sensation or feeling as well; and animals are capable of sensation, according to Leibniz, who decisively rejected the Cartesian doctrine that beasts are nothing but material automata. “On the one hand,” writes McRae, “what distinguishes animals from lower forms of life is sensation or feeling, but on the other hand apperception is a necessary condition of sensation, and apperception distinguishes human beings from animals” (McRae 1976, p. 30). “We are thus left with an unresolved inconsistency in Leibniz's account of sensation, so far as sensation is attributable both to men and animals” (ibid., p. 34).
* Mark Kulstad, Leibniz on Apperception, Consciousness, and Reflection (Munich, Hamden and Vienna: Philosophia Verlag, 1991), 183 pp., US$82.00. Page references are to this work. Adam and Tannery's Oeuvres de Descartes will be cited as AT; Leibniz's works, as they appear in Die Philosophischen Schriften von Gottfried Wilhelm Leibniz, edited by C. I. Gerhard, will be cited as G. [Google Scholar]