In this paper I will discuss the doctrine of substance which emerges from Leibniz’s unpublished early memoir De affectibus of 1679. The memoir marks a new stage in Leibniz’s views of the mind. The motivation for this change can be found in Leibniz’s rejection of the Cartesian theory of passion and action in the 1670s. His early Aristotelianism and some features of Cartesianism persisted to which Leibniz added influences from Hobbes and Spinoza. His nascent dynamical concept of substance is seemingly (...) a combination of old and fresh influences, representing a characteristically eclectic approach, but I will argue that the influence of Hobbes is especially important in the memoir. To do that, I will examine Leibniz’s development in the 1670s up to the De affectibus and consider the nature of affects in the memoir, especially the first affect which starts the thought sequence. This first affect of pleasure or pain is the key to Leibniz’s theory of active substances and in this way to the whole of Leibniz’s moral psychology and ethical metaphysics. (shrink)

In this paper I argue that inconsistencies in scientific theories may arise from the type of causality relation they—tacitly or explicitly—embody. All these seemingly different causality relations can be subsumed under a general strategy developed to defeat the paradoxes which inevitably occur in our experience of the real. With respect to this, scientific theories are just a subclass of the larger class of metaphysical theories, construed as theories that attempt to explain a (part of) the world consistently. All metaphysical theories (...) share a common structural backbone specificially designed to defeat paradoxes, their often wildly diverging ontological claims notwithstanding. This common structure shapes the procedures which govern the invention of ideas in the context of such theories, by codifying some onto-logical a priori assumptions regarding the consistency of reality into its bare conceptual framework. Causality plays a key rôle here, because it implies conservation of identity, itself a far from simple notion. It imposes strong demands on the universalising power of the theories concerned. These demands are often met by the introduction of a metalevel which encompasses the notions of ‘system’ and ‘lawful behaviour’. In classical mechanics, the division between universal and particular leaves its traces in the separate treatment of cinematics and dynamics. The fundamental backbone’s specific gestalt thus functions as a theory’s individual signature and paves the way to a comparative historical approach towards their study. An important part of my paper therefore explores the strong connections between paradoxes as they appear and are dealt with in ancient philosophy and their re-appearance in early modern natural philosophy and science. This analysis is applied to the mechanical theories of Newton and Leibniz, with some surprising results. (shrink)

This article aims to interpret Leibniz’s dynamics project through a theory of the causation of corporeal motion. It presents an interpretation of the dynamics that characterizes physical causation as the structural organization of phenomena. The measure of living force by mv2 must then be understood as an organizational property of motion conceptually distinct from the geometrical or otherwise quantitative magnitudes exchanged in mechanical phenomena. To defend this view, we examine one of the most important theoretical discrepancies of Leibniz’s dynamics with (...) classical mechanics, the measure of vis viva as mv2 rather than ½ mv2. This “error”, resulting from the limits of Leibniz’s methodology, reveals the systematic role of this quantity mv2 in the dynamics. In examining the evolution of the quantity mv2 in the refinement of the force concept from potentia to actio, I argue that Leibniz’s systematic limitations help clarify dynamical causality as neither strictly metaphysical nor mechanical but a distinct level of reality to which Leibniz dedicates the “dynamica” as “nova scientia”. (shrink)

This anthology is about the signal change in Leibniz’s metaphysics with his explicit adoption of substantial forms in 1678-79. This change can either be seen as a moment of discontinuity with his metaphysics of maturity or as a moment of continuity, such as a passage to the metaphysics from his last years. Between the end of his sejour at Paris and the first part of the Hanover period, Leibniz reformed his dynamics and began to use the theory of corporeal substance. (...) This book explores a very important part of the philosophical work of the young Leibniz. Expertise from around the globe is collated here, including Daniel Garber’s work based on the recent publication of Leibniz's correspondence from the late 1690s, examining how the theory of monads developed during these crucial years. Richard Arthur argues that the introduction of substantial forms, reinterpreted as enduring primitive forces of action in each corporeal substance, allows Leibniz to found the reality of the phenomena of motion in force and thus avoid reducing motion to a mere appearance. Amongst other themes covered in this book, Pauline Phemister’s paper investigates Leibniz’s views on animals and plants, highlighting changes, modifications and elaborations over time of Leibniz’s views and supporting arguments and paying particular attention to his claim that the future is already contained in the seeds of living things. The editor, Adrian Nita, contributes a paper on the continuity or discontinuity of Leibniz’s work on the question of the unity and identity of substance from the perspective of the relation with soul and mind. (shrink)

This article discusses some reasons for taking a reconstructive approach to the argumentative structure of Leibniz’s metaphysics. One reason is the fragmentary nature of the countless notes and letters that constitute by far the largest part of Leibniz‘s philosophical output. Another reason is that conjecturing how the many isolated arguments proposed by Leibniz fit into a large-scale argumentative structure could yield insights into how Leibniz made use of the method of intuition – both in his analysis of mind and in (...) his analysis of matter. Contemporary critics have objected that the method of intuition leads to philosophical conservatism, arbitrary choices between conflicting intuitions, and a preoccupation with psychological facts rather than with reality. By contrast, reconstructing the methodology behind Leibniz’s metaphysics could indicate how intuitions could be used in a way that sidesteps these problems. Leibniz gives priority to intuitions concerning the structure of mental operations over intuitions concerning the structure of material objects; this is why intuitions concerning the structure of material objects can be replaced by innovative philosophical theories; these theories, however, make use of metaphysical concepts implied by the analysis of mind and, thereby, can capture facts both about psychology and about the structure of extra-mental reality. (shrink)