Section 17 of Leibniz’s Monadology contains a famous argument in which considerations of what it would be like to enter a machine that was as large as a mill are offered as reasons to reject materialism about the mental. In this paper, I provide a critical discussion of Leibniz’s mill argument, but, unlike most treatments, my discussion will focus on texts other than the Monadology in which considerations of the mill also appear. I provide a survey of three previous interpretations (...) of the argument and a partial defence of one of them, namely the one that Marc Bobro and I offered in Stepping Back Insider Leibniz's Mill (The Monist, 1998). However, I also argue that a fourth interpretation is necessary to account for the appearances of Leibniz’s mill in at least some of his writings. (shrink)

This volume is a critical edition of the eight-year correspondence between Gottfried Wilhelm Leibniz and Burcher de Volder, professor of philosophy and mathematics at Leiden University. Containing the surviving correspondence between Leibniz and De Volder, the volume also presents a generous selection from the letters between Leibniz and his friend Johann Bernoulli, through whose intercession the correspondence began. Bernoulli acted as intermediary throughout, and the often candid discussions between Leibniz and Bernoulli provide illuminating background to the correspondence proper. Each of (...) the selections appears both in the original Latin and in English translation. (shrink)

According to one of Leibniz's theories of contingency a proposition is contingent if and only if it cannot be proved in a finite number of steps. It has been argued that this faces the Problem of Lucky Proof , namely that we could begin by analysing the concept ‘Peter’ by saying that ‘Peter is a denier of Christ and …’, thereby having proved the proposition ‘Peter denies Christ’ in a finite number of steps. It also faces a more general but (...) related problem that we dub the Problem of Guaranteed Proof . We argue that Leibniz has an answer to these problems since for him one has not proved that ‘Peter denies Christ’ unless one has also proved that ‘Peter’ is a consistent concept, an impossible task since it requires the full decomposition of the infinite concept ‘Peter’. We defend this view from objections found in the literature and maintain that for Leibniz all truths about created individual beings are contingent. (shrink)

In a recent paper, Dennis Plaisted examines an important argument that Leibniz gives for the existence of primitive concepts. After sketching a natural reading of this argument, Plaisted observes that the argument appears to imply something clearly inconsistent with Leibniz’s other views. To save Leibniz from contradiction, Plaisted offers a revision. However, his account faces a number of serious difficulties and therefore does not successfully eliminate the inconsistency. We explain these difficulties and defend a more plausible alternative. In the process, (...) we call attention to the neglected topic of Leibniz’s views on the nature of conceiving, and reveal his commitment to the somewhat surprising thesis that one can conceive something through a concept even if one has no conscious grasp of that concept. (shrink)

In 1985 Daniel Garber published his highly intluential paper “Leibniz and the Foundations of Physics: The Middle Years”. In two recent articles, Garber returns to these issues with a new position - that we should perhaps conclude that Leibniz did not have a view concerning the ultimate ontology of substance during his middle years. I discuss the viability of this position and consider some more general methodological issues that arise from this discussion.

Leibniz’s reasons for rejecting materialism are complex and often rely on assumptions that are deeply puzzling to contemporary philosophers. However, the discussion of these issues in § 17 of the Monadology has received a lot of attention over the past couple of decades. For it is here that Leibniz presents the most well known version of his “mill argument.”.

Unlike most of the other great philosophers Leibniz never wrote a magnum opus, so his philosophical correspondence is essential for an understanding of his views. This collection of essays by pre-eminent figures in the field of Leibniz scholarship is a most thorough account of Leibniz's philosophical correspondencee. It both illuminates Leibniz's philosophical views and pays due attention to the dialectical context in which the relevant passages from the letters occur. The result is a book of enormous value to all serious (...) students of early-modern philosophy and the history of ideas. (shrink)

The aim of this paper is to shed light on Leibniz’s justification of the Principle of Sufficient Reason. It approaches this issue through a close textual analysis of the correspondence with Samuel Clarke and a more abstruse and lesser-known writing, ‘Leibniz’s Philosophical Dream’.

This paper is a discussion of the treatment of Leibniz's conception of substance in Heidegger's The Metaphysical Foundations of Logic. I explain Heidegger's account, consider its relation to recent interpretations of Leibniz in the Anglophone secondary literature, and reflect on the ways in which Heidegger's methodology may illuminate what it is to read Leibniz and other figures in the history of philosophy.

This paper explores the issue of Leibniz's commitment to the doctrines of eternal punishment and universal salvation. I argue against the dominant view that Leibniz was committed to eternal punishment, but rather than defending the minority position that Leibniz believed in universal salvation, I suggest that the evidence for his adherence to each is indicative of the way in which he regards religious doctrine as instrumentally valuable. My hypothesis is that Leibniz thought that the appropriateness of advocating eternal damnation, universal (...) salvation or any other eschatological position was a function of the role that it would play in engendering the virtue of true piety in a given audience. (shrink)

Locke and Leibniz on Substance gathers together papers by an international group of academic experts, examining the metaphysical concept of substance in the writings of these two towering philosophers of the early modern period. Each of these newly-commissioned essays considers important interpretative issues concerning the role that the notion of substance plays in the work of Locke and Leibniz, and its intersection with other key issues, such as personal identity. Contributors also consider the relationship between the two philosophers and contemporaries (...) such as Descartes and Hume. (shrink)

According to Robert Sleigh Jr., “The opening remarks of DM.18 make it clear that Leibniz took the results of DM.17 as either establishing, or at least going a long way toward establishing, that force is not identifiable with any mode characterizable terms of size, shape, and motion.” Sleigh finds this puzzling and suggests that other commentators have generally been insufficiently perplexed by the bearing that the DM.17 has on the metaphysical issue. In this brief paper, I examine the solution that (...) Sleigh offers to his puzzle, and present an alternative way of understanding the relationship between these two sections of the Discourse. (shrink)

According to Robert Sleigh Jr., “The opening remarks of DM.18 make it clear that Leibniz took the results of DM.17 as either establishing, or at least going a long way toward establishing, that force is not identifiable with any mode characterizable terms of size, shape, and motion.” Sleigh finds this puzzling and suggests that other commentators have generally been insufficiently perplexed by the bearing that the DM.17 has on the metaphysical issue. He notes that §17 of the Discourse is a (...) presentation of “the argument of the Brevis demonstratio to the effect that Descartes erred in measuring force in terms of mass and velocity, rather than in terms of mass and the square of velocity,” and observes that, given this, it is initially plausible to think that Leibniz ought to have concluded the very opposite, for “if force were measurable in terms of mass and the square of velocity—then force would be characterizable in terms of size and motion.”. (shrink)

The question of Leibniz’s relationship to mysticism has been a topic of some debate since the early part of the 20th Century. An initial wave of scholarship led by Jean Baruzi presented Leibniz mystic. However, later in the 20th Century the mood turned against this view and this negative appraisal holds sway today. In this paper I aim to do two things: First I provide a detailed account of the ways in which Leibniz is critical of mysticism; second, I argue (...) that there is, nonetheless, an important sense in which Leibniz should be regarded as an advocate of mysticism. However, the approach that I take does not focus on an effort to overturn the kinds of considerations that led people to reject the views of Baruzi. Instead, I try to reframe the discussion and explore more complex and interesting relationships that exist between mysticism and Leibniz’s philosophical theology than have been articulated previously. Here I draw on some recent discussions of mysticism in the philosophical literature to illuminate Leibniz’s own distinction between “false mysticism” and “true mystical theology.”. (shrink)

Between 1698 and 1706 Leibniz was engaged in one of his most interesting correspondences, with the Dutch philosopher and physicist Burcher de Volder. The two men were concerned primarily with the question of how the motion of bodies can be explained without appeal to the direct intervention of God. Leibniz presented a naturalistic account of motion to De Volder, but failed to convince him of its adequacy. I shall examine one reason for this failure - the disagreement that arose over (...) the issue of whether there is a substance whose nature is constituted by extension. (shrink)

In this paper I offer a discussion of chapter 3 of Adrian Moore’s The Evolution of Modern Metaphysics, which is titled “Leibniz: Metaphysics in the Service of Theodicy.” Here Moore discusses the philosophy of Leibniz and comes to a damning conclusion. My main aim is to suggest that such a conclusion might be a little premature. I begin by outlining Moore’s discussion of Leibniz and then raise some problems for the objections that Moore presents. I follow this by raising a (...) Moore-inspired problem of my own and offer a possible response. The response is based on a little-known essay of Leibniz’s called “Leibniz’s Philosophical Dream” and leads me to consider Leibniz’s deepest motivations for engaging in philosophical reflection. (shrink)

This paper illuminates Leibniz’s conception of faith and its relationship to reason. Given Leibniz’s commitment to natural religion, we might expect his view of faith to be deflationary. We show, however, that Leibniz’s conception of faith involves a significant non-rational element. We approach the issue by considering the way in which Leibniz positions himself between the views of two of his contemporaries, Bayle and Locke. Unlike Bayle, but like Locke, Leibniz argues that reason and faith are in conformity. Nevertheless, in (...) contrast to the account that he finds in Locke’s Essay, Leibniz does not reduce faith to a species of reasonable belief. Instead, he insists that, while faith must be grounded in reason, true or divine faith also requires a supernatural infusion of grace. (shrink)

It is well known that Leibniz believes that the motion of bodies is caused by an internal force.1 Moreover, he distinguishes between two kinds of force that are associated with bodies, which he calls primitive and derivative forces respectively. My aim is to explain Leibniz’s account of the relation between these two kinds of force, and to address a puzzle that arises in connection with this relation. In fact Leibniz speaks of two different kinds of derivative force. The first, and (...) most fundamental, kind of derivative force is the momentary tendency to move from one perception to another within a simple substance, or monad. Sometimes these are called “appetitions”.2 The second kind are the forces of bodies that are found in the mechanical explanations of Leibnizian Dynamics.3 We shall be concerned primarily with the latter in what follows. However, the derivative forces of monads will also play an important role in the discussion. As one might expect, Leibniz holds that derivative forces are derived from the primitive ones. This idea is more usually expressed in terms of the notion of modification. Thus, derivative forces are said to be “nothing but the modifications and results of primitive forces”4 and to “arise as shapes arise from modification of extension”.5 Here it is natural to assume that Leibniz understands the relation between primitive and derivative force in something like the way in which Descartes understood the relation between modes of extended and thinking substances and the substances themselves, namely as particular ways of being an extended or thinking thing that inhere in their subjects.6 Although this account of derivative forces as modifications of primitive forces may seem plausible at first, difficulties arise when we try to understand how it could apply to the derivative forces in Leibnizian bodies. For it seems to be in conflict with two further aspects of Leibniz’s philosophy. Both can be found in the following passage from a letter to De Volder of 1705.. (shrink)

In discussion of Leibniz’s philosophical methodology Donald Rutherford defends the view that Leibniz regarded metaphysics as an a priori demonstrative science. In the course of this discussion Rutherford isolates and tries to deflect a significant challenge for his view, namely the observation that in many of his mature writings on metaphysics Leibniz appears to defend his views by means of a posteriori arguments. I present some prima facie difficulties with Rutherford’s position and then offer an alternative account of how Leibniz (...) thought he needed to establish metaphysical claims. My suggestion is that the challenge that Rutherford poses may be best answered by attending to the fact that Leibniz recognized a kind of metaphysical enquiry, ‘real metaphysics’, that is essentially a posteriori, in virtue of the fact that it is concerned not just with possible kinds of beings, but with the kinds of beings that God actually created. (shrink)

It has become something of a received view among contemporary scholars that Leibniz first adopted the pre-established harmony around the time of the Discourse on Metaphysics and Correspondence with Arnauld, i.e., 1686-87. However, in their recent contribution to the Cambridge Companion to Leibniz, Christia Mercer and Robert Sleigh Jr. have challenged this orthodoxy by claiming that Leibniz was committed to the doctrine, in all but name, by April 1676. In the present paper, I argue that the evidence that Mercer and (...) Sleigh present to support their somewhat radical thesis is problematic in a number of respects. But rather than embracing the ‘received view’, I present further evidence in favor of the view that Leibniz had in fact adopted the pre-established harmony by 1679. (shrink)

This volume presents introductory chapters from internationally-renowned experts on eleven of Leibniz's key philosophical writings. Offering accessible accounts of the ideas and arguments of his work, along with information on their composition and context, this book is an invaluable companion to the study of Leibniz.

Thanks to the efforts of Paul Schrecker and John W. Nason some half century ago, the University of Pennsylvania is home to microfilm reproductions of over one hundred thousand hand-written pages drawn from the collection of Leibniz’s papers presently housed in the Niedersächsische Landesbibliothek, Hannover. The microfilms are to be found on the mezzanine floor of the reference section in the Van Pelt Library and are readily accessible to visitors. Xerox copies may be made, although the Van Pelt Library stresses (...) that the microfilms remain the property of the Niedersächsische Landesbibliothek, and that permission to copy must be obtained from Hannover beforehand. (shrink)

Seine Kritik an Descartes' Auffassung vom Körper gründet Leibniz bekanntlich auf Erörterungen zur Teilbarkeit und Ausdehnung. Obgleich jene Argumentation im Fokus einer Auseinandersetzung mit Leibniz' Metaphysik angesiedelt werden muss, ist sie bisher nicht recht verstanden worden. Mein Anliegen hier ist im Kern, Leibniz' Gedankengang zu explizieren und dessen Stichhaltigkeit auszuleuchten. Das Argument, um das es geht, ist wohl am ehesten aus der Darlegung in Leibniz' Korrespondenz mit Antoine Arnauld bekannt, findet sich jedoch zudem im späteren Briefwechsel mit De Volder. Neben (...) Parallelen gibt es zwischen den Verfahrensweisen, die Leibniz in den zwei Korrespondenzen jeweils favorisiert, gleichwohl derart signifikante Differenzen, dass es nicht unbegründet scheint, ihm auch zwei Argumentationslinien zuzuschreiben -die Unterschiede dieser Linien werde ich im Folgenden auch hinsichtlich ihres Entstehungszusammenhangs beleuchten und einen Ausblick auf weitere Forschungserfordernisse wagen. (shrink)

contemporaries, Bayle and Locke. Unlike Bayle, but like Locke, Leibniz argues that reason and faith are in conformity. Nevertheless, in contrast to the account that he finds in Locke’s Essay, Leibniz does not reduce faith to a species of reasonable belief. Instead, he insists that, while faith must be grounded in reason, true or divine faith also requires a supernatural infusion of grace.

Page 116 According to Robert Sleigh Jr., “The opening remarks of DM.18 make it clear that Leibniz took the results of DM.17 as either establishing, or at least going a long way toward establishing, that force is not identifiable with any mode characterizable terms of size, shape, and motion.”†2 Sleigh finds this puzzling and suggests that other commentators have generally been insufficiently perplexed by the bearing that the DM.17 has on the metaphysical issue. He notes that §17 of the Discourse (...) is a presentation of “the argument of the Brevis demonstratio to the effect that Descartes erred in measuring force in terms of mass and velocity, rather than in terms of mass and the square of velocity,”†3 and observes that, given this, it is initially plausible to think that Leibniz ought to have concluded the very opposite, for “if force were measurable in terms of mass and the square of velocity†4—then force would be characterizable in terms of size (mass) and motion.”†5.. (shrink)

In discussion of Leibniz’s philosophical methodology Donald Rutherford defends the view that Leibniz regarded metaphysics as an a priori demonstrative science. In the course of this discussion Rutherford isolates and tries to deflect a significant challenge for his view, namely the observation that in many of his mature writings on metaphysics Leibniz appears to defend his views by means of a posteriori arguments. I present some prima facie difficulties with Rutherford’s position and then offer an alternative account of how Leibniz (...) thought he needed to establish metaphysical claims. My suggestion is that the challenge that Rutherford poses may be best answered by attending to the fact that Leibniz recognized a kind of metaphysical enquiry, ‘real metaphysics’, that is essentially a posteriori, in virtue of the fact that it is concerned not just with possible kinds of beings, but with the kinds of beings that God actually created. (shrink)

Schon in seinen frühen Jahren war Leibniz ein Gegner der Cartesischen Naturphilosophie, ca. 1697 zeigt sich in seinen Texten dann ein Argument gegen Descartes, das ich im folgenden behandle und als ,heterogeneity argument‘ bezeichnen möchte - eingangs wird hier dargestellt, wie Leibniz es im Paragraphen 13 seiner Schrift De ipsa natura expliziert, anschließend diskutiere ich zwei frühere Ansätze, die sich um das Thema drehen und die darin einig sind, daß Leibniz Descartes' Auffassung von der materiellen Welt aus a priori - (...) Gründen kritisiert, da sie intern inkonsistent bleibt: Ich versuche nachzuweisen, daß diese Interpretationen Leibniz nicht gerecht werden und plädiere für eine a posteriori - basierte Auslegung - Leibniz zieht Descartes' Ansatz in Zweifel, indem er sich auf ,contingentia‘ hinsichtlich der Art beruft, in der unsere Sinneswahrnehmung die materielle Welt repräsentiert. Zum Abschluß erörtere ich einige allgemeinere hermeneutische Probleme, die sich aus den Unterschieden zwischen früheren Interpretationen und meiner eigenen Deutung nun ergeben. (shrink)

It has become something of a received view among contemporary scholars that Leibniz first adopted the pre-established harmony around the time of the Discourse on Metaphysics and Correspondence with Arnauld, i.e., 1686-87. However, in their recent contribution to the Cambridge Companion to Leibniz, Christia Mercer and Robert Sleigh Jr. have challenged this orthodoxy by claiming that Leibniz was committed to the doctrine, in all but name, by April 1676. In the present paper, I argue that the evidence that Mercer and (...) Sleigh present to support their somewhat radical thesis is problematic in a number of respects. But rather than embracing the ‘received view’, I present further evidence in favor of the view that Leibniz had in fact adopted the pre-established harmony by 1679. (shrink)

Thanks to the efforts of Paul Schrecker and John W. Nason some half century ago, the University of Pennsylvania is home to microfilm reproductions of over one hundred thousand hand-written pages drawn from the collection of Leibniz’s papers presently housed in the Niedersächsische Landesbibliothek, Hannover. The microfilms are to be found on the mezzanine floor of the reference section in the Van Pelt Library and are readily accessible to visitors. Xerox copies may be made, although the Van Pelt Library stresses (...) that the microfilms remain the property of the Niedersächsische Landesbibliothek, and that permission to copy must be obtained from Hannover beforehand. (shrink)