This book reveals a thread that runs through Leibniz’s metaphysics: from his logical notion of possible individuals to his notion of actual, nested ones. It presents Leibniz’s subtle approach to possibility and explores some of its consequential repercussions in his metaphysics. The book provides an original approach to the questions of individuation and relations in Leibniz, offering a novel account of Leibniz’s notion of Nested Individuals.

This volume brings together a number of original articles by leading Leibniz scholars to address the meaning and significance of Leibniz’s notions of compossibility and possible worlds. In order to avoid the conclusion that everything that exists is necessary, or that all possibles are actual, as Spinoza held, Leibniz argued that not all possible substances are compossible, that is, capable of coexisting. In Leibniz’s view, the compossibility relation divides all possible substances into disjoint sets, each of which constitutes a possible world, or a way that God might have created things. For Leibniz, then, it is the compossibility relation that individuates possible worlds; and possible worlds form the objects of God’s choice, from among which he chooses the best for creation. Thus the notions of compossibility and possible worlds are of major significance for Leibniz’s metaphysics, his theodicy, and, ultimately, for his ethics. Given the fact, however, that none of the approaches to understanding Leibniz’s notions of compossibility and possible words suggested to date have gained universal acceptance, the goal of this book is to gather a body of new papers that explore ways of either refining previous interpretations in light of the objections that have been raised against them, or ways of framing new interpretations that will contribute to a fresh understanding of these key notions in Leibniz’s thought.

The Actual and the Possible presents new essays by leading specialists on modality and the metaphysics of modality in the history of modern philosophy from the seventeenth to the twentieth centuries. It revisits key moments in the history of modern modal doctrines, and illuminates lesser-known moments of that history. The ultimate purpose of this historical approach is to contextualise and even to offer some alternatives to dominant positions within the contemporary philosophy of modality. Hence the volume contains not only new scholarship on the early-modern doctrines of Baruch Spinoza, G. W. F. Leibniz, Christian Wolff and Immanuel Kant, but also work relating to less familiar nineteenth-century thinkers such as Alexius Meinong and Jan Lukasiewicz, together with essays on celebrated nineteenth- and twentieth-century thinkers such as G. W. F. Hegel, Martin Heidegger and Bertrand Russell, whose modal doctrines have not previously garnered the attention they deserve. The volume thus covers a variety of traditions, and its historical range extends to the end of the twentieth century, addressing the legacy of W. V. Quine's critique of modality within recent analytic philosophy.

This book presents a comprehensive examination of Gottfried Leibniz's views on the nature of agents and their actions. Julia Jorati offers a fresh look at controversial topics including Leibniz's doctrines of teleology, the causation of spontaneous changes within substances, divine concurrence, freedom, and contingency, and also discusses widely neglected issues such as his theories of moral responsibility, control, attributability, and compulsion. Rather than focusing exclusively on human agency, she explores the activities of non-rational substances and the differences between distinctive types of actions, showing how the will, appetitions, and teleology are key to Leibniz's discussions of agency. Her book reveals that Leibniz has a nuanced and compelling philosophy of action which has relevance for present-day discussions of agency. It will be of interest to scholars and students of early modern philosophy as well as to metaphysicians and philosophers of action.

Gonzalo Rodriguez-Pereyra presents an original study of the place and role of the Identity of Indiscernibles in Leibniz's philosophy. The Principle of the Identity of Indiscernibles rules out numerically distinct but perfectly similar things; Leibniz derived it from more basic principles and used it to establish important philosophical theses. Rodriguez-Pereyra aims to establish what Leibniz meant by the Principle of Identity of Indiscernibles, what his arguments for and from it were, and to assess those arguments and Leibniz's claims about the Principle of Identity of Indiscernibles. He argues that Leibniz had a very strong version of the principle, according to which no possibilia (whether or not they belong to the same possible world) are intrinsically perfectly similar, where this excludes things that differ in magnitude alone. The book discusses Leibniz's arguments for the Identity of Indiscernibles in the Meditation on the Principle of the Individual, the Discourse on Metaphysics, Notationes Generales, Primary Truths, the letter to Casati of 1689, the correspondence with Clarke, as well as the use of the Identity of Indiscernibles in Leibniz's arguments against the Cartesian conception of the material world, atoms, absolute space and time, the Lockean conception of the mind as a tabula rasa, and freedom of indifference. Rodriguez-Pereyra argues that the Identity of Indiscernibles was a central but inessential principle of Leibniz's philosophy.

In Living Mirrors, Ohad Nachtomy examines Leibniz's attempt to "re-enchant" the natural world-that is, to infuse life, purpose, and value into the very foundations of nature, a nature that Leibniz saw as disenchanted by Descartes' and Spinoza's more naturalistic and mechanistic theories. Nachtomy sees Leibniz's nuanced view of infinity- how it differs in the divine as well as human spheres, and its relationship to numerical and metaphysical unity-as key in this effort. Leibniz defined living beings by means of an infinite nested structure particular to what he called "natural machines"-and for him, an intermediate kind of infinity is the defining feature of living beings. Using a metaphor of a "living mirror," Leibniz put forth infinity as crucial to explaining the unity of a living being as well as the harmony between the infinitely small and the infinitely large; in this way, employing infinity and unity, we can better understand life itself, both as a metaphysical principle and as an empirical fact. Nachtomy's sophisticated and novel treatment of the essential themes in Leibniz's work will not only interest Leibniz scholars, but scholars of early modern philosophy and students of the history of philosophy and science as well.

This volume congregates articles of leading philosophers about potentials and potentiality in all areas of philosophy and the empirical sciences in which they play a relevant role. It is the first encompassing collection of articles on the metaphysics of potentials and potentiality. Potentials play an important role not only in our everyday understanding of objects, persons and systems but also in the sciences. An example is the potential to become an adult human person. Moreover, the attribution of potentials involves crucial ethical problems. Bioethics makes references to the theoretical concept "potential" without being able to clarify its meaning. However, despite its relevance it has not been made subject of philosophical investigation. Mostly, potentials are regarded as a subspecies of dispositions. Whilst dispositions are a flourishing field of research, potentials as such have not come into focus. Potentials like dispositions are modal properties. But already a first glance at the metaphysics of potentials shows that concerning their ascription potentials are more problematic than dispositions since "potential" means that an entity has the potential to acquire a property in the future. Therefore, potentials involve a time structure of the entities in question that is much more complex than those of dispositions. This handbook brings this important concept into focus in its various aspects for the first time. It covers the history of the concept as well as contemporary systematic problems and will be of special interest for philosophers in the fields of general metaphysics, philosophy of science and ethics, especially bioethics. It will also be of interest to scientists and persons concerned with bioethical problems.