Leibniz: Metaphysics

In this article I interpret resilience and evolution in view of the philosophy of Leibniz. First, I discuss resilience as a substance’s or a monad’s “quantity of essence” — its “degree of perfection” — which I express as the quality of the Whole with respect to the sum of the qualities of the Parts. Then I discuss evolution, which I interpret here as the autopoietic Principle that sets Itself in motion and creates all reality, including Itself. This Principle may be (...) considered as a sort of ante-litteram metaphysical Darwinian Selection. My interpretations provide a different formulation for questions such as “why natural evolution evolves?” and “why is this the best of all possible worlds?” In this article I also provide a geometrical interpretation of a key aspect behind the “divine mathematics” of the autopoietic Principle. (shrink)

This paper argues that, contrary to what one might think, early modern rationalism displays an increasing and well-grounded sensitivity to certain metaphysical questions the substantial form was designed to answer – despite the fact that the notion itself was in such disrepute, and emphatically banished from natural philosophy. This main thesis is established by examining the thought of Descartes, Spinoza, and Leibniz through the framework constituted by what have been designated as the two aspects, metaphysical and physical, of the substantial (...) form. This examination shows that Descartes ends up assigning the soul a notable metaphysical task formerly assigned to the substantial form, whereas Spinoza advances a theory of essences motivated by the philosophical concerns behind the two aspects of the substantial form. Leibniz finally makes a sharp distinction between natural philosophy and metaphysics as he develops a dynamistic theory that deliberately aims at understanding the substantial form in a new fashion. This line of development is designated as one major factor contributing to the separation of philosophy and natural science. -/- . (shrink)

Leibniz initially believed in the absoluteness of time and place, but later he changed his idea. His true and final view is that time and place are relative and subjective concepts, whereas Newton believed that they are absolute and have a real and objective existence independent of other phenomena. In his correspondence with Samuel Clark, he refers to the weak points of the views of Newton and Clark and presents several philosophical and theological arguments to reject them. Time and place (...) are treated in his philosophy ontologically, and their existence is relative. Epistemologically speaking, these concepts correspond to phenomena and depend on external phenomena and objects. From a psychological point of view, these concepts are formed in the mind through observing the relations among objective phenomena. Time and place are attributes of phenomena rather than monads or simple substances.In contrast to Newton's idea, the existence of an empty place or vacuum is impossible and in contradiction to Leibniz's accepted principles. He has presented some metaphysical and theological arguments on rejecting this issue in most of his works. (shrink)

As far as treatments of causation are concerned, the pre-Kantian 18th century German context has long been dismissed as a period of uniform and unrepentant Leibnizian dogmatism. While there is no question that discussions of issues relating to causation in this period inevitably took Leibniz as their point of departure, it is certainly not the case that the resulting positions were in most cases dogmatically, or in some cases even recognizably, Leibnizian. Instead, German theorists explored a range of positions regarding (...) the nature of causal powers, the appropriate systems to explain the observed agreement between the states of substances, and the ground of free actions, or so I will argue in this chapter. Focusing on these three issues, I will here sketch the development of the debates relating to causation and trace the evolution of positions among the philosophers within the so-called Leibnizian-Wolffian philosophy as well as among its many opponents. (shrink)

In eighteenth-century post-Leibnizian German philosophy, the debate on immortality did not concern only the fate of the soul after death but also the fate of the body. Leibniz had famously maintained that no animal ever dies, for the soul is never entirely deprived of its living body. In spite of Bilfinger’s almost isolated defense, this doctrine never became dominant, even among Leibniz’s followers. Christian Wolff, long considered a mere popularizer of Leibniz’s philosophy, departed from this account of immortality and replaced (...) it with the traditional Platonic model, based on the survival of separated souls. After reconstructing Leibniz’s, Wolff’s, and Bilfinger’s positions, this paper considers how the debate evolved within the so-called Wolffian school during the 1730s and 1740s. Both partisans and detractors of separated souls diverged from Leibniz on a crucial point: namely, they argued that another key Leibnizian doctrine, pre-established harmony, entails that the soul need not be forever united to its body. Furthermore, the cases of Johann Heinrich Winckler, Johann Gustav Reinbeck, Israel Gottlieb Canz, and even Alexander Gottlieb Baumgarten show that the post-Leibnizian detractors of separated souls drew, in fact, more inspiration from the neo-Platonic and esoteric doctrine of the subtle body than from Leibniz’s original immortalism. (shrink)

En el presente trabajo estudiamos el concepto de naturaleza en Leibniz y Boyle y la fundamentación que a partir de dicha noción cada uno ofrece del mecanicismo. De modo más específico, proponemos que De ipsa natura de Leibniz se articula como un debate póstumo con A Free Enquiry into the Vulgarly Received Notion of Nature de Boyle, siendo el objetivo inicial del texto leibniziano revisar la concepción boyleana de naturaleza y ofrecer una fundamentación alternativa del mecanicismo que permita introducir una (...) comprensión internalista de las leyes naturales. Palabras Clave: Leibniz, Boyle, naturaleza, mecanicismo, fuerza. (shrink)

Leibniz argues against Descartes’s conception of material substance based on considerations of unity. I examine a key premise of Leibniz’s argument, what I call the Plurality Thesis—the claim that matter (i.e. extension alone) is a plurality of parts. More specifically, I engage an objection to the Plurality Thesis stemming from what I call Material Monism—the claim that the physical world is a single material substance. I argue that Leibniz can productively engage this objection based on his view that matter is (...) discrete. The discreteness of matter provides two aspects of support for the Plurality Thesis. First, it indicates that the parts of matter do not share boundaries and are, therefore, independent in an important sense. Second, it indicates that the parts of matter are determinate and are, therefore, ontologically prior to the wholes they compose. (shrink)

This paper reconsiders Leibniz’s conception of the nature of possible things and offers a novel interpretation of the actualization of possible substances. This requires analyzing a largely neglected notion, the reality of individual essences. Thus far scholars have tended to construe essences as representational items in God’s intellect. We acknowledge that finite essences have being in the divine intellect but insist that they are also grounded in the infinite essence of God, as limitations of it. Indeed, we show that it (...) is critical to understand that this dependence on God’s essence is prior to the dependence on God through divine ideas. Here it is crucial to distinguish questions concerning the ontological status of essences from questions concerning their reality. This yields a fresh view of Leibniz’s theory of creation, which takes seriously his claim that the same thing is first a mere possibility but after creation an actually existent substance. (shrink)

The concept of every real thing from all eternity contains the unavoidability of its existence before the divine decision. Thus every complete concept of a real thing contains the property of being such that the thing will exist if a created universe exists. Then a thing's existence cannot be external to its concept. There is bound to be more in the concept of something that exists than in that of "something" that does not-since existence is explained through the quidditative property (...) of being an essence that constitutes an integral part of the most perfect series of things. Such an essential, quidditative perfection explains the divine decision, and hence existence. Therefore, existence can be deduced from that essential perfection. The essence-as-such, the mere possible, contains something from which existence follows. What Leibniz never manages to explain is what distinguishes existence from the quidditative perfection it unavoidably stems from. (edited). (shrink)

Leibniz was a philosopher of principles: the principles of Contradiction, of Sufficient Reason, of Identity of Indiscernibles, of Plenitude, of the Best, and of Continuity are among the most famous Leibnizian principles. In this article I shall focus on the first three principles; I shall discuss various formulations of the principles (sect. 1), what it means for these theses to have the status of principles or axioms in Leibniz’s philosophy (sect. 2), the fundamental character of the Principles of Contradiction and (...) Sufficient Reason (sect. 3), some attempts to demonstrate the Principles of Contradiction and Sufficient Reason (sect. 4), and one attempt to demonstrate the Principle of Identity of Indiscernibles (sect. 5). The main results of the chapter are summarized in a short conclusion (sect. 6). (shrink)

This paper aims to show that Deleuze’s ideas on space and extension are heavily in debt to Leibniz. The focus is on chapter five, ‘the Asymmetrical Synthesis of the Sensible’, of Difference and Repetition. Concepts such as ‘intensive magnitude’, ‘distance’, ‘order’ and most importantly ‘spatium’ are shown to have their origin in Leibniz’s philosophy. In order to do so, the article starts with Leibniz’s critique on Cartesian mechanics and how this leads Leibniz to a conception of space that goes beyond (...) the Cartesian concept of extension. The latter lacks difference, potentiality and individuality. Leibniz argues that the Cartesian homogeneous plenum should therefore be grounded in a deeper more substantial space: the spatium. Understood as such, space is not an absolute substance but a structure of relations between substances. Although Leibniz’s texts offer enough to understand this spatium, they do not explain how the genesis of extension out of space should be understood. It is on this point that Deleuze offers a fruitful interpretation of Leibniz by conceptualizing such a genesis in terms of difference. Extension is understood as a homogenization and externalization of the internal and pure differences in space. In the end, Leibniz helps us to understand Deleuze’s theory, while Deleuze offers us an enriching interpretation of Leibniz that succeeds where authors such as Yvon Belaval and Martial Gueroult have failed. (shrink)

The Principle of Sufficient Reason —the principle that everything has a reason—plays a central role in Leibniz’s philosophical system. It is rather difficult, however, to determine what Leibniz’s attitude towards the modal status of the PSR is. The prevailing view is that Leibniz takes the PSR to be true necessarily. This paper develops a novel interpretation and argues that Leibniz’s PSR is a contingent principle. It also discusses whether a merely contingent PSR can do the metaphysical heavy lifting that Leibniz (...) aims for. The paper shows that, despite appearance to the contrary, this is possible. In a nutshell, the argument is that the only possible PSR violation Leibniz allows for is God’s creation of a suboptimal world; there is no Leibnizian possible world, though, which intrinsically violates the PSR. Despite its contingency, then, Leibniz’s PSR is modally robust enough to serve as a foundational principle of his metaphysics. (shrink)

This paper locates a source of contingency for Leibniz in the fact that God can do otherwise, absolutely speaking. This interpretative line has been previously thought to be a dead-end because it appears inconsistent with Leibniz’s own conception of God, as the ens perfectissimum, or the most perfect being (Adams, 1994). This paper points out that the best argument on offer which seeks to demonstrate this inconsistency fails. The paper then argues that the supposition that God does otherwise implies for (...) Leibniz (at least) that God would not be praiseworthy, which is an absurd implication—or a violation of the principle of sufficient reason (PSR)—but that this is not, strictly speaking, an inconsistency—or a violation of the principle of contradiction (POC). While praiseworthiness is a perfection—and is compossible with God’s other perfections—and so God must instantiate it, this paper argues that, given the nature of praiseworthiness for Leibniz, it in fact makes sense to say that praiseworthiness is merely a contingent perfection of God. (shrink)

El presente artículo ofrece un análisis del concepto de continuidad, tal como fue desarrollado por dos de sus principales exponente, Leibniz y Peirce. Comienza por definir el significado del concepto, señalando las diferentes propiedades del continuum identificadas en ambos autores. Después señala las consecuencias y aplicaciones filosóficas que el concepto tiene para ambos filósofos, en especial para la ontología. En primer lugar, expone lo que Leibniz llamó la ley de continuidad y sus diferentes versiones. Luego, se habla de lo que (...) Peirce denominó «sinequismo», que constituye el conjunto de ideas de este filósofo acerca de la continuidad y de sus implicaciones filosóficas. Aquí se intenta mostrar, especialmente, como el sinequismo constituye la clave para la comprensión de muchos problemas lógicos, epistemológicos y metafísicos, como el de la validez de los axiomas de la lógica, la justificación del conocimiento, el dualismo mente cuerpo, el evolucionismo y el realismo acerca de los universales. (shrink)

I argue for a novel interpretation of Leibniz’s conception of the kind of contingency that matters for freedom, which I label ‘agential contingency.’ In brief, an agent is free to the extent that she determines herself to do what she judges to be the best of several considered options that she could have brought about had she concluded that these options were best. I use this novel interpretation to make sense of Leibniz’s doctrine that the reasons that explain free actions (...) are merely inclining and not necessitating. (shrink)

Leibniz famously argues that there must be simple substances, since there are composites, and a composite is nothing but a collection of simples. I reconstruct Leibniz’s argument, showing that it relies on a commitment to mereological nihilism. I show further that Leibniz endorses mereological nihilism as early as the 1680s and offers both direct and indirect support for this commitment: indirect support via the notion of unity and direct support via the notion of persistence. I then assess the alignment of (...) Leibniz’s mereological nihilism with his other commitments during the 1680s, including his potential commitment to corporeal substances. I argue that any viable interpretation of Leibniz’s commitment to corporeal substances is compatible with mereological nihilism, which provides a new perspective both on Leibniz’s developing theory of substance and on his mature theory of simple substance. (shrink)

The problem at the center of this essay is how one can reconcile the continuity of space with a monadological theory of matter, according to which matter is ultimately composed of simple elements, a problem that greatly exercised Leibniz, the Wolffians, and Kant. The underlying purpose of this essay is to illustrate my reading of Kant’s philosophical development, and of his relation to the Wolffians and Leibniz, according to which, (a), this development was fueled by ‘home-grown’ problems that arose within (...) the framework of the Wolffian philosophy from which Kant started out, and, (b), on his journey to critical idealism, Kant gradually moved away from Wolffianism, but closer to Leibniz, which, however, he came to realize only some years after the publication of the Critique of Pure Reason. This reading is illustrated by showing that the problem of how to reconcile the continuity of space with a monadological theory of matter is a problem that Kant inherits from Leibniz and the Wolffians, in whose thinking it already plays an important role, that Leibniz’s mature solution to the problem differs markedly from the Wolffian solution, and that Kant’s early, pre-critical solution is largely Wolffian, while his later critical solution is largely Leibnizian, as he himself notes with gleeful satisfaction. The discussion also reveals that this problem is one of the key problems that fueled Kant’s philosophical development and, eventually, led him to the discovery of transcendental idealism. (shrink)

This paper is a new translation and interpretation of the essay by Leibniz which has come to be known as “Leibniz’s Philosophical Dream.” Leibniz used many different literary styles throughout his career, but “Leibniz’s Philosophical Dream” is unique insofar as it combines apparent autobiography with a dreamscape. The content is also somewhat surprising. The essay is reminiscent of Plato, insofar as Leibniz describes a transition from existence in a cave to a more enlightened mode of being outside of it. But, (...) in contrast with the usual identification of Leibniz as a “rationalist,” the mode of being that is valorised involves cognition that is intuitive and supra-rational. The paper begins with the translation followed by an interpretation of the essay. I conclude by considering the ramifications of my interpretation for our conception of Leibniz’s philosophy. (shrink)

La traduction latine du livre de Maïmonide Moreh Nevukhim | Guide des égarés, a été l'ouvrage juif le plus influent des derniers millénaires (Di Segni, 2019 ; Rubio, 2006 ; Wohlman, 1988, 1995 ; Kohler, 2017). Elle marqua le début de la scolastique, fille du judaïsme élevée par des penseurs juifs, selon l'historien Heinrich Graetz (Geschichte der Juden, L. 6, Leipzig 1861, p. xii). Imprimée par la première presse mécanique de Gutenberg, son influence en Occident s'étendit jusqu'au Vème concile du (...) Latran (1512-1517) « où les savants furent encouragés à lever les difficultés qui semblaient diviser l'ensemble de la théologie et de la philosophie — (Leibniz, Théodicée, 11 ) ». Pendant des siècles, le Guide a révolutionné le programme d'instruction scolaire en réintégrant dans le domaine de la foi les lois de la pensée (dont la quatrième est devenue le principe de la raison suffisante de Leibniz). Cette collection complète de notes qui expose les idées du Guide fournit tous les passages sélectionnés et réécrits par Leibniz. Cette première traduction complète bilingue annotée des manuscrits originaux en latin sert de porte d'entrée à la foi conforme à la Raison. -/- « L'excellent livre du Rabbin Moïse Maïmonide, le Guide des égarés, est plus philosophique que je ne l'avais imaginé et mérite une lecture attentive. L'auteur, distingué par son intelligence en philosophie, était versé dans les mathématiques, l'art médical, et aussi dans la connaissance de Saintes Écritures. » — G. W. LEIBNIZ, 1685, Anthologie de Leibniz du Guide de Maïmonide, Chapitre III. (shrink)

La traducción al latín de la obra de Maimónides Moreh Nevukhim | Guía para Perplejos, ha sido la obra judía más influyente en los últimos milenios (Di Segni, 2019; Rubio, 2006; Wohlman, 1988, 1995; Kohler, 2017). Ésta marcó el comienzo de la escolástica, «hija del judaísmo nutrida por pensadores judíos, » según el historiador Heinrich Graetz (Geschichte der Juden, L. 6, Leipzig 1861, p. xii). Impresa por la primera imprenta mecánica de Gutenberg, su influencia en Occidente se extendió hasta el (...) Quinto Concilio de Letrán (1512-1517) « donde se instó a los eruditos a eliminar las dificultades que parecían dividir el conjunto de la teología y la filosofía (Leibniz, Teodicea, 11 ). » Durante siglos, la Guía revolucionó el currículo de estudios de la instrucción escolar al reintegrar en el ámbito de la fe las leyes del pensamiento (la cuarta de las cuales se convirtió en el principio de la razón suficiente de Leibniz). La colección completa de las notas que exponen las ideas de la Guía incluye todos los pasajes seleccionados y reescritos por Leibniz. Esta primera traducción bilingüe completa y anotada de los manuscritos originales en latín sirve como una puerta de entrada a la fe conforme a la Razón. -/- « El excelente libro del rabino Moisés Maimónides, Guía para perplejos, es más filosófico de lo que había imaginado y merece una lectura atenta. El autor, distinguido por su inteligencia filosófica, fue versado en matemáticas, en el arte de la medicina, y también en el conocimiento de las Sagradas Escrituras. » — GW LEIBNIZ, 1685. Antología de Leibniz de la Guía de Maimónides, Capítulo III. (shrink)

Rosi Braidotti has recently argued that the emerging scholarship on posthumanism should employ what she calls nomadic thinking. Braidotti identifies Gilles Deleuze’s work on Spinoza as the genesis of posthumanist ontology, yet Deleuze’s claims about nomadic thinking or nomadology come from his work on Leibniz. I argue that for posthumanist thought to theorize subjectivity beyond the human, it must use nomadology to overcome ontology itself. To make my argument, I demonstrate that while Braidotti is correct about Spinoza’s influence on Deleuze, (...) his work on Leibniz is necessary to adequately conceptualize nomadology. I employ Deleuze and Guattari’s figure of the Thought-brain as a model for conceptualizing posthumanist subjectivity that they claim goes beyond the subject itself. (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)

This chapter explores the relationship between the views of Leibniz and Berkeley on the fundamental nature of the created universe. It argues that Leibniz concurs with Berkeley on three key points: that in the final analysis there are only perceivers and their contents (subjective idealism), that there are strictly speaking no material or corporeal substances, and that bodies or sensible things reduce to the contents of perceivers (phenomenalism). It then reconstructs his central argument for phenomenalism, which rests on his belief (...) in the infinite division of matter, his doctrine of the ideality of relations, and the traditional principle of the convertibility of being and unity. Finally, it explores Leibniz’s belief that a body having its being in one perceiver can be “founded” on other perceivers, and considers Berkeley’s reasons for opposing such a view. (shrink)

This article examines the fundamental ontological significance that the category of perception has in philosophy of G.W. Leibniz, and establishes the connection between the category of perception and modern panpsychism. There is a problem of definition of protopsychic properties in modern panpsychism. The problem is expressed not only in the absence of such a definition, but also in the absence of a good strategy for finding possible candidates for the role of protopsychic property. To solve this problem, the author considers (...) the status of the monad as the center of perception in Leibniz’s monadology, as well as the question of the relation of different monads to each other. Based on Leibniz’s ideas, the following modifications for modern panpsychism have been proposed, among others. First, it was proposed that protopsychic properties be viewed as properties that represent all reality in some vague way, preventing the emergence of high-level psychic properties. Second, it was proposed that mental properties be viewed not as a combination of protopsychic properties, but as state of protopsychic properties. This means that to form high-level mental properties, protopsychic properties must not only form some system, but must also be partially blocked. The author also considers the question of whether it is possible to borrow the proposed ideas in modern panpsychism. The problem for this is the ontological differences between modern naturalistic panpsychism and Leibniz’s classical panpsychism. The article proposes three different strategies for dealing with this problem related to three interpretations of Leibniz’s philosophy. First, it is possible to limit ourselves to considering physics as a set of structural phenomena derived from the activity of monads. Second, it is possible to try to show that there is some other, non-causal, type of relationship between the monads. Third, it is possible to consider this system as naturalistic pantheism and assume that God is a mediator and a common non-spatial coordinate system through which the monads agree with each other. (shrink)

In the Theodicy, Leibniz argues against two impious conceptions of God—a God who makes arbitrary choices and a God who doesn’t make choices at all. Many interpret Leibniz as navigating these dangers by positing a kind of non-Spinozistic necessitarianism. I examine passages from the Theodicy which reject not only blind necessitarianism but necessitarianism altogether. Leibniz thinks blind necessitarianism is dangerous due to the conception of God it entails and the implications for morality. Non-Spinozistic necessitarianism avoids many of these criticisms. Leibniz (...) finds that even necessary actions should receive certain rewards and punishments as long as they necessarily lead to a change in future behavior. But Leibniz rejects even non-Spinozistic necessitarianism on the grounds that it is inconsistent with punitive justice. Whether Leibniz successfully avoids necessitarianism, it ought to be clear that he sees his own position as significantly distinct from necessitarianism and not just Spinozism. (shrink)

This book presents fresh interpretations of Gottfried Leibniz's theories of time, space, and the relativity of motion, based on a thorough examination of Leibniz's manuscripts as well as his published papers. These are analysed in historical context, but also with an eye to their contemporary relevance.

El presente trabajo de investigación tiene por objetivo reconstruir la noción de identidad práctica tanto en Aristóteles como en Leibniz, a fin de mostrar en qué medida el hannoveriano es deudor del Estagirita y en qué medida se distingue una propuesta de la otra. Para lograr esto hacemos dos cosas: por un lado, analizamos la noción aristotélica de praxis y de agencia moral a la luz de su noción de habituación; por otro lado, damos cuenta de la dimensión práctica que (...) el hannoveriano adscribe a su noción de identidad personal, a partir de sus nociones de conscientia y cualidad moral. -/- The purpose of this research is to reconstruct the notion of practical identity in both Aristotle and Leibniz in order to show to what extent, the Hanoverian is indebted with Aristotle and to what extent one proposal can be distinguished from the other. To achieve this we do two things: on the one hand, we analyze the Aristotelian notion of praxis and moral agency trough his notion of habituation; on the other hand, we notice the practical dimension that Leibniz assigns to his notion of personal identity, based on his notions of conscientia and moral quality. (shrink)

Leibniz and Kant were heirs of a biblical theistic tradition which viewed miraculous activity in the world as both possible and actual. But both were also deep explanatory rationalists about the natural world: more committed than your average philosophical theologian to its thoroughgoing intelligibility. These dual sympathies—supernaturalist religion and empirical rationalism—generate a powerful tension across both philosophers’ systems, one that is most palpable in their accounts of empirical miracles—that is, events in nature that violate one or more of the natural (...) laws. The primary goal of this chapter is to exhibit their respective efforts to resolve this tension, and to show how Kant’s noumenal ignorance doctrine allows him to set aside some key difficulties that Leibniz’s model leaves unresolved. The chapter concludes with the unorthodox suggestion that both systems leave conceptual space for the idea that finite free beings, rather than just God, can produce empirical miracles. (shrink)

Philosophers often rely on the notion of conceptual containment and apply mereological terminology when they talk about the parts or constituents of a complex concept. In this paper, I explore two historical approaches to this general notion. In particular, I reconstruct objections Bernard Bolzano puts forward against a criterion that played a prominent role in the history of philosophy and that was endorsed, among others, by Leibniz. According to this criterion, a concept that represents objects contains all and only the (...) concepts that represent properties the objects must have in order to be represented by the former concept. Bolzano offers several counterexamples and arguments against the criterion. I argue that while some of them presuppose a strongly mereological understanding of containment, which Leibniz is not committed to, one of them also succeeds without relying on demanding mereological principles. (shrink)

The article explores the relationship between Locke and Leibniz's account of space and how this impacts on their understanding of possibility, and particularly practical choices between possibilities within a modal space. Using Borges' short story 'Pierre Menard, author of the Quixote' it argues that Locke's acquiescence to absolute space severely restricts his account of the power to do things. Leibniz's retention of relative space permits a much richer account of possible, yet he binds these worlds together under a universal set (...) of principles which are morally true in every possible world. He calls these morally impossible (prohibited), echoing the Scholastic language of repugnance. 'Menard' is employed to critique this resort to universality, before an alternative possible truth structure is sketched as a response to the 'self-evident' truths defended by Leibniz. (shrink)

In the controversy that arose between Gottfried Wilhelm Leibniz and Georg Ernst Stahl following the publication of the latter’s Theoria medica vera, both theoreticians strove to distance themselves from what they took to be the classical conception of the vegetative soul, while relating and partly reducing their opponent’s doctrine to it. I shall first attempt to establish their respective meanings for such a soul and the reasons why they would challenge the relevance of that notion for physiology. I shall then (...) try to show how they nevertheless integrated explanatory functions equivalent to those attributed to that metaphysical entity into the theoretical frameworks they proposed and favoured. As a consequence of alternative interpretations of this kind, eighteenth-century physiologists will tend to link vegetative life either with “organic mechanism” or with various kinds of “vital principle,” akin to Stahl’s anima. (shrink)

In the second edition of Hermann Cohen’s Kant’s Theory of Experience, he abandons the interpretation of Kant’s Anticipations of Perception that he gave in the first edition, in favourof a radically different one. On his early interpretation, the Anticipations is largely of psychological interest for its influence on, and continuing significance for, physiological psychology and psychophysics. But on his mature interpretation, it defends the superiority of a dynamic conception of nature over a mechanical conception. Further, on his early interpretation, Cohen (...) thought the Anticipations was not a central part of Kant’s critical theory of knowledge. But on his mature interpretation, he thinks it is absolutely central to that project. What is more, Cohen seems to have revised his interpretation in a relatively short period of time, in 1880-1. This paper argues that Cohen’s change in views about Kant’s Anticipations is explained by his reception of Leibniz in the very early 1880s, and specifically Cohen’s reception of Leibniz’s arguments against Descartes’ view that extension is the essence of matter. (shrink)

Saul Kripke may have argued that unicorns could not possibly exist, but if you’re personally unconvinced, you’d be in good company. When he wasn’t busy independently inventing infinitesimal calculus and devising his famous theodicy, Gottfried Wilhelm Leibniz found time to write about unicorns in what would become Protogaea.

In a 1687 letter to Arnauld, Leibniz draws on an argument against mind-body causation that is reminiscent of one from Spinoza’s Ethics. According to this argument, mind-body causation is impossible because of the lack of proportion between thoughts and motions. This paper aims to shed light on Leibniz’s use of Spinoza’s argument by reconstructing both its internal structure and its development in Leibniz’s later works. In particular, the reconstruction focuses on the new version of this argument that Leibniz adopts against (...) Stahl’s vitalism as well as on the change that this new version reveals in Leibniz’s attitude towards occasionalism. The possible influence of Cordemoy is also taken into consideration. The epistemological and metaphysical issues surrounding this argument are an essential part of the history of Leibniz’s psycho-physical parallelism. (shrink)

I discuss an objection by Margaret Wilson against Robert Brandom’s interpretation of Leibniz’s account of perceptual distinctness. According to Brandom, Leibniz holds that (i) the relative distinctness of a perception is a function of its inferentially articulated content and (ii) apperception, or awareness, is explicable in terms of degrees of perceptual distinctness. Wilson alleges that Brandom confuses ‘external deducibility’ from a perceptual state of a monad to the existence of properties in the world, with ‘internally accessible content’ for the monad (...) in that state. Drawing on Leibniz, I develop a response to Wilson on Brandom’s behalf. (shrink)

Kant attacks the Leibnizians on various fronts but the objection that occurs most frequently in his writings is that they are committed to an untenable conception of the relation between sensible and intellectual representations. They regard the difference between intellectual and sensible representations as a merely ‘logical’ difference that concerns their form, namely, their different degrees of distinctness, while in truth it is a difference in kind that concerns their nature, origin, and content. In the first part of this essay, (...) I provide a detailed reconstruction of what exactly this objection amounts to, and show why Kant takes this misconception to be so significant that he keeps coming back to it over and over again. The misconception is so significant because virtually all of the other mistaken doctrines of the Leibnizians can be traced back to it. Several commentators have argued that Leibniz is not guilty of the confusion of sensible and intellectual representations that Kant accuses him of. But this does not automatically clear him from all the other errors that Kant takes to be closely connected with this confusion. In the second part of this essay, I take a look at Leibniz's theory of confused perceptions and examine whether he is committed to one of these errors, namely, the view that we could learn something about things in themselves by experience if our senses were acute enough or our powers of 'disfusing' perceptions were strong enough. (shrink)

The way Leibniz applied his philosophy to mathematics has been the subject of longstanding debates. A key piece of evidence is his letter to Masson on bodies. We offer an interpretation of this often misunderstood text, dealing with the status of infinite divisibility innature, rather than inmathematics. In line with this distinction, we offer a reading of the fictionality of infinitesimals. The letter has been claimed to support a reading of infinitesimals according to which they are logical fictions, contradictory in (...) their definition, and thus absolutely impossible. The advocates of such a reading have lumped infinitesimals with infinite wholes, which are rejected by Leibniz as contradicting the part–whole principle. Far from supporting this reading, the letter is arguably consistent with the view that infinitesimals, as inassignable quantities, arementis fictiones, i.e., (well-founded) fictions usable in mathematics, but possibly contrary to the Leibnizian principle of the harmony of things and not necessarily idealizing anything inrerum natura. Unlike infinite wholes, infinitesimals—as well as imaginary roots and other well-founded fictions—may involve accidental (as opposed to absolute) impossibilities, in accordance with the Leibnizian theories of knowledge and modality. (shrink)