ライプニッツにおける内的現象と外的現象 : 一七〇一―一六年を手がかりに

Abstract

In his letter to De Voider of June 30 1704, Leibniz notes that a body or matter is not a substance, but a phenomenon of a percipient being or perceiver (G2 270). The best commentators have been outspoken about this doctrine. Thus Louis Loeb reminds us that for Leibniz bodies do not exist outside of perceiving minds. According to Loeb, June 1704 marks a decisive claim in Leibniz's theory of body, from which we can understand that Leibniz is a phenomenalist. Another interpretation is made by Donald Rutherford, who admits that the thesis in the letter to De Voider may seem to support a phenomenalistic interpretation, yet insists that "phenomena" in that thesis can still be taken as "well-founded phenomena, " or aggregates of substances. In his interpretation, understanding bodies requires us to look at something external to our own perception, since bodies are aggregates of substances which are external to perceivers. Thus Rutherford claims that "the 'reality' of these phenomenal aggregates 'is located in the harmony of the percipients with themselves (at different times) and with other beings, ' i.e. in relations among the perceptual phenomena of the monads constituting the aggregate." Here Rutherford understands phenomenal aggregates as aggregates of substances rather than a mere appearance or perception. However, in this paper I will propose another kind of interpretation. First, I will interpret phenomena in that thesis as representational contents which are internal for perceivers. At that point my position is closer to Loeb's. Secondly, on the other hand, I admit that even after June 1704 Leibniz often emphasizes that bodies actually are aggregates of simple substances, and these aggregates cannot be reduced to perceptions of perceivers. Both Loeb and Rutherford seem to take the terms "phenomenon" and "body" too narrowly, since Loeb understands that phenomena must be internal perceptions while Rutherford always takes bodies to be aggregates of substances. In the first section, I introduce the notion of internal phenomenon, which is identified to the representational content of a perceiving mind. In the second section, I explain the notion of external phenomenon. Leibniz often regards aggregates of simple substances as "phenomena, " but this kind of phenomenon is clearly not internal since unlike representational contents aggregates are actually made up of many simple substances. But the existence of an aggregate of simple substances in some sense depends upon a mind even though it is constituted by many external simple substances (G2 256; G5 133 NE 2.12.7 etc.). Considering this dependence, Leibniz assigned the term "phenomenon" to an aggregate of simple substances. In the third and forth sections, I critically examine univocal interpretations of "phenomenon" and "body." Montgomery Furth, Loeb and Glenn Hartz were wrong in supposing that the term "phenomenon" only refers to representational contents. Also, despite Rutherford's interpretation, the term "body" sometimes refers to an internal phenomenon. In the fifth section, I contrast my approach with the interpretation made by Robert Adams, which takes an aggregate of substances to be internal for a perceiver. In the last section, I conclude that aggregates of substances are external objects of perceiving minds, and Leibniz is a realist in that he often regards bodies as things outside of perceivers.