On Unity and Simple Substance in Leibniz

Abstract

What is Leibniz's argument for simple substances? I propose that it is an extension of his prior argument for incorporeal forms as principles of unity for individual corporeal substances. The extension involves seeing the hylomorphic analysis of corporeal substances as implying a resolution of matter into forms, and this seems to demand that forms, which are themselves simple, be the only elements of things. The argument for simples thus presupposes the existence of corporeal substances as a key premise. Yet a theory of simple substances as the elements of things threatens to preclude the existence of corporeal substances for Leibniz, and the extension of the argument for forms into an argument for simples is not cogent. If nothing else rides on the simplicity of individual substances, then perhaps instead of being its most fundamental tenet, the doctrine of simples-the monadology-is something that over-extends and destabilizes Leibniz's metaphysics.

2. Simple Substances and Composite Bodies (§§ 1–5)

“…In this vein, it has been argued that Leibniz cannot consistently uphold the doctrine that the only true unities are monads, since the concept of the monad is a generalization of the idea of an immaterial soul or form, which is the principle of unity of some corporeal substance. Thus, if monads exist, there must exist corporeal substances, whose souls the monads are (Levey 2007).…”

“…The Analysis Problem is paired with a second puzzle, which I will call the Construction Problem (Levey 2007). Suppose that reality consists ultimately of simple, mind-like substances.…”

The Logic of Leibniz’s Borrowed Reality Argument

“…1 My aim in what follows is to clarify the underlying logic of this argument. In particular, I will be concerned with understanding Leibniz's rationale for the crucial premise that not all reality can be borrowed, a rationale that I believe has been missed both by Leibniz scholars and by 1 The name appears to originate with Levey (2007), who also calls it the "derivedreality argument " (2003: 261). Others have called this general line of thought the "aggregate argument" (Garber 2009: 74-76, 88-89) and the "presupposition argument" (Arthur 2011: 100-1).…”

“…Others have called this general line of thought the "aggregate argument" (Garber 2009: 74-76, 88-89) and the "presupposition argument" (Arthur 2011: 100-1). For discussions of other possible arguments for simples in Leibniz, see Levey (2007;2012) along with the responses of Rutherford (2008b) and Doggett (2010).…”

Leibniz’s Metaphysics and Metametaphysics: Idealism, Realism, and the Nature of Substance

“…1 1 View (a) is advocated by Mercer (2001); view (b) by Sleigh (1990), Adams (1994), Rutherford (1995, 2008), and Cover and Hawthorne (1999); view (c) is advocated most prominently by Garber (1985, 2009); and view (d) by Loptson (1999), Loptson and Arthur (2006), Phemister (2005), Levey (2007), Hartz (2007), and Smith (forthcoming). There are many subtle differences within each group, but this will serve as a rough picture of the field.…”