ABSTRACTThe most prominent early modern argument against materialism is to be found in Descartes. Previously I had argued that this argument relies crucially on a robust conception of substance, according to which it has a single principal attribute of which all its other intrinsic qualities are modes. In the present paper I return to this claim. In Section 2, I address a question that is often raised about that conception of substance: its commitment to the idea that a substance has (...) a single such principal attribute. Gonzalo Rodriguez-Pereyra and Daniel Garber have argued that this claim relies on Descartes's identification of substance with attribute. But I argue that it relies on his view that a substance has a single, unitary nature. In Section 3, I examine the role of this conception of substance in arguments found in Malebranche and Leibniz and compare these arguments with Descartes's. (shrink)

This article discusses Leibniz’s claim that every substance is endowed with the property of perception in connection with Platonism, rationalism and the problem of substance monism. It is argued that Leibniz’s ascription of perception to every substance relies on his Platonic conception of finite things as imitations of God, in whom there is ‘infinite perception’. Leibniz’s Platonism, however, goes beyond the notion of imitation, including also the emanative causal relation and the logical (i.e. definitional) priority of the absolute over the (...) limited. It is proposed that Leibniz’s endorsement of Platonism, in conjunction with some rationalist elements of his philosophy, implies a monistic conception of particulars as modifications of a single substance. Following some scholars and opposing others, the article offers evidence that Leibniz accepted this implication during the last years of his Paris period. However, it is further argued that it was precisely the idea of perception as a property of every substance that allowed Leibniz to find a way out of monism after that period. More specifically, the article defends the view that what made room for ontological pluralism within Leibniz’s rationalist and Platonic outlook was the idea that perception is the property which constitutes the very being of substances: substances are their perceptions. (shrink)

Leibniz argues that there must be a fundamental level of simple substances because composites borrow their reality from their constituents and not all reality can be borrowed. I contend that the underlying logic of this ‘borrowed reality argument’ has been misunderstood, particularly the rationale for the key premise that not all reality can be borrowed. Contrary to what has been suggested, the rationale turns neither on the alleged viciousness of an unending regress of reality borrowers nor on the Principle of (...) Sufficient Reason, but on the idea that composites are phenomena and thus can be real only insofar as they have a foundation in substances, from which they directly ‘borrow’ their reality. The claim that composites are phenomena rests in turn on Leibniz's conceptualism about relations. So understood, what initially looked like a disappointingly simple argument for simples turns out to be a rather rich and sophisticated one. (shrink)

I propose a straightforward reconciliation of Leibniz’s conception of bodies as aggregates of simple substances (i.e., monads) with his doctrine that bodies are the phenomena of perceivers, without in the process saddling him with any equivocations. The reconciliation relies on the familiar idea that in Leibniz’s idiolect, an aggregate of Fs is that which immediately presupposes those Fs, or in other words, has those Fs as immediate requisites. But I take this idea in a new direction. Taking notice of the (...) fact that Leibniz speaks of three respects in which one thing may immediately presuppose others--i.e., with respect to its being, its existence, and its reality--I argue that a phenomenon having its being in one perceiving substance (monad) can plausibly be understood to presuppose other perceiving substances (monads) in two of these respects. Accordingly, good sense can be made of both the claim that a phenomenon in one monad is an aggregate of other monads (in Leibniz’s technical sense of 'aggregate') and the (equivalent) claim that the latter monads are constituents of the phenomenon (in his technical sense of 'constituent'). So understood, the two conceptions of body are perfectly compatible, just as Leibniz seems to think. (shrink)

I examine several alleged grounds of the principle of sufficient reason in Leibniz’s philosophy. These include the nature of a requisite and a sufficient condition, the nature of truth, and the nature of harmony. I argue that Leibniz does not ground the PSR in any of these ways. Instead, he is committed to a value-based grounds of the PSR: God creates the best possible world, and the fact that the PSR obtains in this world contributes to it being the best. (...) I conclude by considering some objections to this way of grounding the PSR. (shrink)

In Matter and Memory, Bergson identifies a problem with perception and resolves it by arguing that matter is an aggregate of images. However, it is unclear whether and how Bergson justifies this thesis, and interpreters differ considerably on this question. This paper formulates and analyzes Bergson’s arguments for this thesis in Chapter 1 of Matter and Memory. Bergson presents five arguments, some of which echo arguments in early modern philosophy. They jointly compose a substantive, well-structured defense of his thesis. This (...) paper also illuminates an aspect of Bergson’s method that departs from his famous reliance on intuition and is grounded in his conception of the clarity required in philosophy. (shrink)

Leibniz’s mature philosophical understanding of the laws of nature emerges rather suddenly in the late 1670’s to early 1680’s and is signaled by his embrace of three central theses.1 The first, what I’ll call the thesis of Contingency, suggests that the laws of nature are not only contingent, but, in some sense, paradigmatically contingent; they are supposed to provide insight into the very nature of contingency as Leibniz comes to understand it. The second, what I’ll call the thesis of Providence, (...) suggests that the laws of nature provide a basis for a new argument from design by showing how reflection on God’s ends can be positively useful in the practice of natural philosophy. The third, what I’ll call thesis of .. (shrink)

I shall proceed in the following way. In parts II and III of this paper, I shall discuss the strengths and weaknesses of the interpretation put forward by Robert Merrihew Adams in his recent book, and I shall expand upon this account, discussing a crucial but hitherto unexamined aspect of the relation between dominant and subordinate monads, reconstructed from Leibniz's letters to Des Bosses and his essays of 1714, _Principles of Nature and Grace and Monadology. In part IV of this (...) paper, I shall examine various difficulties that arise both for my interpretation and, more generally, for Leibniz's account of the relation of domination and subordination. (edited). (shrink)

The article is a critical notice of Daniel Garber, Leibniz: Body, Substance, Monad. Garber presents a developmental reading of Leibniz's metaphysics that focuses on Leibniz's evolving analysis of body and force as the key to his account of substance. Garber claims that Leibniz shifts from an early theory of body to a theory of corporeal substance in his middle years, and only develops a theory of monads in his later writings—and that even then Leibniz looks not to abandon the scheme (...) of corporeal substances but to reconcile it with that of monads. The present article considers several challenges to Garber's interpretation, questioning, among other things, Garber's claims about development and Garber's account of Leibniz's primary arguments for the theory of monads. The article concludes that while crucial elements of the standard interpretation of Leibniz as an idealist can be defended against Garber's critique, the original traditional view that takes the theory of monads as the first and most fundamental principle of Leibniz's metaphysics is no longer sustainable. (shrink)

This article examines Leibniz's philosophy of causation with the aim of clarifying how causes are related to their effects. I argue that, much like J. L. Mackie's INUS conditions, Leibnizian causes are members of complex causal conditions. More precisely, Leibniz identifies causes with elements of complex causal conditions, where the complex condition as a whole is sufficient for the effect, and the cause is a necessary part of that condition. This conception of causation is able to incorporate Leibniz's many other (...) definitions of ‘cause’, thereby resolving what appear to be internal inconsistencies in his philosophy of science. Introduction The ingredients of causation Causes and conditions Causes as INUS conditions Conclusion. (shrink)

Resumen En el presente trabajo analizo el concepto de cuerpo en los escritos maduros de Leibniz. En el marco del debate contemporáneo acerca del estatus de la sustancia corpórea examino el entramado de las tres nociones sobre las que se construye la metafísica leibniziana de los cuerpos, a saber, la de materia prima, la de cuerpo orgánico y la de extensión. En cada caso evalúo el estatus ontológico que Leibniz les reconoce así como el papel que cumplen en su metafísica.In (...) this paper I examine the concept of body in Leibniz’s mature writings. In the context of the contemporary debate on the status of the corporeal substance, I analyze the relation between the three notions from which he builds his metaphysics of bodies, namely, the primary matter, the organic body, and the extension. For each case I evaluate their ontological status and the role they play in his metaphysics. (shrink)

According to Leibniz's late metaphysics, sensory perception represents to us as extended, colored, textured, etc., a world which fundamentally consists only of non-spatial, colorless entities, the monads. It is a short step from here to the conclusion that sensory perception radically misleads us about the true nature of reality. In this paper, I argue that this oft-repeated claim is false. Leibniz holds that in typical cases of body perception the bodies perceived really exist and have the qualities, both primary and (...) secondary, they are perceived to have. At the same time, Leibniz holds that our perceptions of these bodies are accurate representations of the monads from which the bodies result. The contrary thesis — that our body perceptions are misrepresentations of the monads — stems from a misunderstanding of Leibniz's theory of confused concepts and his phenomenalist account of the nature of body. Clarifying these issues will have important consequences for our understanding of Leibniz's idealistic metaphysics and the manner in which that metaphysical theory is meant to support mechanistic science. (shrink)

I argue that Leibniz consistently subscribes to the view that phenomena (thus bodies) have their being in perceiving substances. I then argue that this mentalistic conception of phenomenon coheres with three of his doctrines of body: (1) that bodies presuppose the unities or simple substances on which they are founded; (2) that bodies are aggregates of those substances; and (3) that bodies derive or borrow their reality from their simple constituents.