Leibnizian idealism

Abstract

According to most interpreters, Gottfried Wilhelm Leibniz (1646–1716) held a strong form of idealism according to which simple mental substances and their features exhaust fundamental reality. Leibniz called these substances monads (from the Greek word monas, ‘one’ or ‘unit’), and he assigns them two main features: (i) perceptual representations, and (ii) tendencies to move from one set of representations to the next. In more traditional interpretations of Leibniz, although monads are ultimately immaterial and non-located, material reality and everything in it derives from them and their two main features (Adams, 1994; Baxter, 1995; Rutherford, 1995, 2008; Cover & O’Leary-Hawthorne, 1999; Duarte, 2015, 2017; Look, 2010, 2013; Look & Rutherford, 2007: pp. xix–lxxii; Mercer, 2001; Pearce, 2016; Puryear, 2016; Sleigh, 1990; Whipple, 2017). Not all interpreters entirely agree with this assessment. Some argue that Leibniz held nonidealist views (Arthur, 1998; Bolton, 2004; Broad, 1975; Fichant, 2003; Garber, 1985, 2009; Hartz, 1998, 2007; Hartz & Wilson, 2005; Jolley, 1986; Lodge, 2014; Loptson, 1999; Loptson & Arthur, 2006; Phemister, 1999, 2005). Others argue that Leibniz’s views developed substantially over time or that he never clearly settled on one side or the other (Garber, 2004, 2005, 2009: pp. 382–388; Hartz, 2007; Lodge, 2005; Wilson, 1999). Recently, McDonough (2013) has argued that Leibniz remained deliberately non-committal between idealism and non-idealism and that his deeply held views were compatible with both. At the heart of these disagreements lies Leibniz’s treatment of corporeal substance.1 Despite Leibniz’s frequent claim that the universe ultimately boils down to monads, he also sometimes appears to say that the world’s fundamental furniture includes extended, corporeal substances. Was Leibniz an idealist, then, or not? I do think Leibniz was an idealist. John Whipple (2015, 2017) argues compellingly that some of the apparently anti-idealist passages in Leibniz stem from a range of rhetorical and pedagogical strategies meant to bridge the gap between his idealism and the non-idealism of his interlocutors. When we factor in these strategies, as well as the wider body of work, it seems to me much more likely than not that Leibniz was a firmly committed idealist, especially in his later years. However, even if we grant that Leibniz was an idealist, di"cult questions remain about his particular brand of idealism. In this chapter, I try to o#er, in the sense of Rutherford 11 LEIBNIZIAN IDEALISM