In a text written during his stay in Paris, Leibniz, to deny ontological reality to relations, employs an argument well known to the medieval thinkers and which later would be revived by Francis H. Bradley. If one assumes that relations are real and that a relation links any property to a subject – so runs the argument – then one falls prey to an infinite regress. Leibniz seems to be well aware of the consequences that this argument has for his (...) own metaphysical views, where the relation of inherence (‘inesse’) plays such a central role. Thus, he attempts first to interpret the relation of inherence as something ‘metaphoric’, originating from our ‘spatial way’ of looking at the surrounding world; and then he tries to reduce it to the part-whole relation which clearly he considers weaker, from the ontological point of view, than that of ‘being in’. (shrink)

In this paper I argue that what has been called Leibniz’s “aggregate argument” for unities in things in fact comprises three quite distinct lines of argument, with different concepts being advanced under the name ‘unity’ and meriting quite different conceptual treatment. Two of those arguments, what I call the Borrowed Reality Argument and the Multitude Argument, also appear in later writings to be further elaborated into arguments not just for unities but for simples. I consider the arguments in detail. I (...) suggest that one of the two, the Borrowed Reality Argument, is philosophically more promising and has the stronger evidence for being central in Leibniz’s thought as he argues for the existence of simple substances. (shrink)

The aim of this paper is to trace in Leibniz’s drafts the sketched outline of a conceptual framework he organized around the key concept of ‘requisite’. We are faced with the project of a semi-formal theory of conditions, whose logical skeleton can have a lot of different interpretations. In particular, it is well suited to capture some crucial relations of ontological dependence. Firstly the area of ‘mediate requisites’ is explored - where causal and temporal relations are dealt with on the (...) basis of a general theory of ‘consequence’.Then the study of ‘immediate requisites’ is taken into account - a true sample of mereological inquiry, where Leibniz strives for a unitary treatment of part-whole relation, conceptual inclusion and inherence. Far from simply conflating these relations one with another and with causality, therefore, Leibniz tried to spell them out, while at the same time understanding them within a single conceptual framework. (shrink)

This paper consists in a study of Leibniz’s argument for the infinite plurality of substances, versions of which recur throughout his mature corpus. It goes roughly as follows: since every body is actually divided into further bodies, it is therefore not a unity but an infinite aggregate; the reality of an aggregate, however, reduces to the reality of the unities it presupposes; the reality of body, therefore, entails an actual infinity of constituent unities everywhere in it. I argue that this (...) depends on a generalized notion of aggregation, according to which a thing may be an aggregate of its constituents if every one of its actual parts presupposes such constituents, but is not composed from them. One of the premises of this argument is the reality of bodies. If this premise is denied, Leibniz’s argument for the infinitude of substances, and even of their plurality, cannot go through. (shrink)

Legendary since his own time as a universal genius, Gottfried Wilhelm Leibniz (1646-1716) contributed significantly to almost every branch of learning. One of the creators of modern mathematics, and probably the most sophisticated logician between the Middle Ages and Frege, as well as a pioneer of ecumenical theology, he also wrote extensively on such diverse subjects as history, geology, and physics. But the part of his work that is most studied today is probably his writings in metaphysics, which have been (...) the focus of particularly lively philosophical discussion in the last twenty years or so. The writings contain one of the great classic systems of modern philosophy, but the system must be pieced together from a vast and miscellaneous array of manuscripts, letters, articles, and books, in a way that makes especially strenuous demands on scholarship. This book presents an in-depth interpretation of three important parts of Leibniz's metaphysics, thoroughly grounded in the texts as well as in philosophical analysis and critique. The three areas discussed are the metaphysical part of Leibniz's philosophy of logic, his essentially theological treatment of the central issues of ontology, and his theory of substance (the famous theory of monads). (shrink)

In the present book, Pauline Phemister argues against traditional Anglo-American interpretations of Leibniz as an idealist who conceives ultimate reality as a plurality of mind-like immaterial beings and for whom physical bodies are ultimately unreal and our perceptions of them illusory. Re-reading the texts without the prior assumption of idealism allows the more material aspects of Leibniz's metaphysics to emerge. Leibniz is found to advance a synthesis of idealism and materialism. His ontology posits indivisible, living, animal-like corporeal substances as the (...) real metaphysical constituents of the universe; his epistemology combines sense-experience and reason; and his ethics fuses confused perceptions and insensible appetites with distinct perceptions and rational choice. In the light of his sustained commitment to the reality of bodies, Phemister re-examines his dynamics, the doctrine of pre-established harmony and his views on freedom. The image of Leibniz as a rationalist philosopher who values activity and reason over passivity and sense-experience is replaced by the one of a philosopher who recognises that, in the created world, there can only be activity if there is also passivity; minds, souls and forms if there is also matter; good if there is evil; perfection if there is imperfection. (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)

This translation of Suarez's 54th Disputation documents the ancient Greek and Medieval sources of his discussion. It also considers Suarez's influence upon hitherto unknown late scholastic writers and the relevance of his intentionality theory to figures such as Descartes and Kant.

Gottfried Wilhelm Leibniz was one of the central figures of seventeenth-century philosophy, and a huge intellectual figure in his age. This book from Glenn A. Hartz is an advanced study of Leibniz's metaphysics. Hartz analyzes a very complicated topic, widely discussed in contemporary commentaries on Leibniz, namely the question of whether Leibniz was a metaphysical idealist, realist, or whether he tried to reconcile both trends in his mature philosophy. Because Leibniz is notoriously unclear about this, much has been written on (...) the subject. In recent years, the debate has centered on whether it is possible to maintain compatibility between the two trends. In this controversial book, Hartz demonstrates that it is not possible to maintain compatibility of idealist and realist views - they must be understood as completely separate theories. As the first major work on realism in Leibniz's metaphysics, this key text will interest international Leibniz scholars, as well as students at the graduate level. (shrink)

Daniel Garber presents a study of Leibniz's conception of the physical world, elucidating his puzzling metaphysics of monads, mind-like simple substances.

Robert M. Adams behauptet, daß Leibniz' zwei Konzeptionen der Körper als bloße Phänomene und als Aggregate von Substanzen konsistent und somit Bestandteile einer einzigen Theorie der Phänomene seien. Dagegen möchte ich hier zeigen, daß Adams' Strategie, Körper als intentionale Objekte der Perzeption zu verstehen - als objektive Realität von Ideen im kartesischen Sinn - nicht vereinbar damit ist, sie als Aggregate von Substanzen aufzufassen. Mit Adams stimme ich insofern überein, als Aggregate von Monaden sich nur im Geist als Einheit finden, (...) ich bestreite jedoch, daß nur im Geist die Aggregate dann auch sind. (shrink)

In der neuen Literatur tiber Leibniz' Spatphilosophie findet man zwei deutlich einander entgegengesetzte Theorien Uber die Realitat des Körpers. Auf der einen Seite gibt es Gesichtspunkte, die ihn mit einer Phänomenalismuslehre verbinden, nach welcher die Körper nichts anderes als koordinierte Perzeptionen unausgedehnter Monaden sind. Auf der anderen Seite gibt es Griinde, die dafur sprechen, daß Leibniz die Auffassung vertreten muß, daß Körper Aggregate von Monaden sind. In diesem Aufsatz suche ich zu zeigen, daß die phanomenalistische Interpretation aufgrund der starken Textzeugnisse, (...) die Leibniz beständig zur Aggregatthese hindrängen, zuriickzuweisen ist. Daruber hinaus weise ich jedoch die verbreitete Auffassung eben der Aggregatthese zurück, d. h. die Meinung, gewisse Vielheiten von Monaden riefen bloß die Illusion, Körper zu sein, hervor, wenn sie durch andere Monaden M falsch perzipiert" werden. Gegen diese Auffassung des falschen Perzipierens ftihre ich ins Feld, daß die Aggregatthese als ein Deutungsversuch der Natur oder des Wesens des Körpers verstanden werden mufi. Wenn Leibniz sagt, Körper seien Aggregate von Monaden, so ist das nicht als blofie Behauptung, gewisse Monaden erschienen anderen Monaden als Körper, zu verstehen, sondern als die These, daß jeder Körper seinem Wesen nach eine Vielheit von Monadenist. (shrink)

This essay offers an alternative account of Leibniz’s views on substance and fundamental ontology. The proposal is driven by three main ideas. First, that Leibniz’s treatment should be understood against the backdrop of a traditional dispute over the paradigmatic nature substance as well as his own overarching conciliatory ambitions. Second, that Leibniz’s metaphysics is intended to support his conciliatory view that both traditional views of substance are tenable in at least their positive and philosophical respects. Third, that the relationship between (...) immaterial substances, corporeal substances, and ordinary bodies in Leibniz’s metaphysics is best understood as one of “material” constitution. The interpretation as a whole thus suggests that Leibniz needn’t be read as offering either an exclusive defense of corporeal substance realism, nor of immaterial substance idealism, nor as being deeply torn (at a time or over time) between two such views. He may instead be seen as offering a carefully presented, consistent, and sophisticated conciliatory account of substance. (shrink)

Leibniz est-il devenu phénoménaliste pendant ses années dernières ? Contre Furth et Loeb, ce travail rend une réponse négative à cette question. Quoique Leibniz a caressé les idées phénoménalistes, il ne les a jamais vraiment acceptées ; au contraire, il soutient une autre thèse réductioniste, c'est-à-dire que les corps sont des agrégats des monades. Cependant, cette conclusion entraîne ses propres difficultés, car à certains égards, la doctrine phénoménaliste paraît plus satisfaisante que l'option concurrante. On soutient que la répugnance leibnizienne à (...) accepter le phénoménalisme doit s'expliquer par son dessein de concilier la monadologie et la physique. (shrink)