The main objective of this Element is to reconstruct Aristotle's view on the nature of ontological priority in the Categories. Over the last three decades, investigations into ontological dependence and priority have become a major concern in contemporary metaphysics. Many see Aristotle as the originator of these discussions and, as a consequence, there is considerable interest in his own account of ontological dependence. In light of the renewed interest in Aristotelian metaphysics, it will be worthwhile - both historically and systematically - to return to Aristotle himself and to see how he himself conceived of ontological priority (what he calls 'priority in substance' [proteron kata ousian] or 'priority in nature' [proteron tēi phusei]), which is to be understood as a form of asymmetric ontological dependence.

Aristotelian (or neo-Aristotelian) metaphysics is currently undergoing something of a renaissance. This volume brings together fourteen essays from leading philosophers who are sympathetic to this conception of metaphysics, which takes its cue from the idea that metaphysics is the first philosophy. The primary input from Aristotle is methodological, but many themes familiar from his metaphysics will be discussed, including ontological categories, the role and interpretation of the existential quantifier, essence, substance, natural kinds, powers, potential, and the development of life. The volume mounts a strong challenge to the type of ontological deflationism which has recently gained a strong foothold in analytic metaphysics. It will be a useful resource for scholars and advanced students who are interested in the foundations and development of philosophy.

Aristotle's views on the fundamental nature of reality are usually taken to be inconsistent. Two sources for these views are Categories and the central books of Metaphysics. This text argues that he is engaged in different projects in these books.

Cleary discusses the origin, development, and use of the many senses of priority as a central thesis in Aristotle's metaphysics. Cleary contends that one of the most revealing problems for the ambiguity of Aristotle's relationship to Platonism is that of the ontological status of mathematical objects. In support of his claim, Cleary analyzes a curious passage from Aristotle's Topics, where he appears to accept a schema of priorities that makes mathematical entities more substantial than sensible things. How does Aristotle try to reconcile the ordering of things dictated by sciences like mathematics and dialectic with the ordering of sense experience upon which his own physics and metaphysics are based? To find the answer, Cleary reviews three different outlines of the many senses of priority given by Aristotle himself and found in Categories 12-13, Metaphysics Delta 11, and Metaphysics Theta 8. Cleary suggests there is an implicit hierarchy for Aristotle that leads him to posit the Prime Mover at its apex as complete actuality and, therefore, as the focus for the concept of priority. Having reviewed Aristotle's treatment of the many uses of priority, Cleary demonstrates how the concept is used in some typical arguments by Aristotle for his mature metaphysical positions.

Christian Pfeiffer explores an important, but neglected topic in Aristotle's theoretical philosophy: the theory of bodies. A body is a three-dimensionally extended and continuous magnitude bounded by surfaces. This notion is distinct from the notion of a perceptible or physical substance. Substances have bodies, that is to say, they are extended, their parts are continuous with each other and they have boundaries, which demarcate them from their surroundings. Pfeiffer argues that body, thus understood, has a pivotal role in Aristotle's natural philosophy. A theory of body is a presupposed in, e.g., Aristotle's account of the infinite, place, or action and passion, because their being bodies explains why things have a location or how they can act upon each other. The notion of body can be ranked among the central concepts for natural science which are discussed in Physics III-IV. The book is the first comprehensive and rigorous account of the features substances have in virtue of being bodies. It provides an analysis of the concept of three-dimensional magnitude and related notions like boundary, extension, contact, continuity, often comparing it to modern conceptions of it. Both the structural features and the ontological status of body is discussed. This makes it significant for scholars working on contemporary metaphysics and mereology because the concept of a material object is intimately tied to its spatial or topological properties.

The idea that some parts of reality are fundamental and others derivative was an important one in Aristotle's philosophical system, and is now again of great current interest in philosophy. Michail Peramatzis presents a new account of priority relations in Aristotle's metaphysics, and draws out their continuing philosophical significance.

This volume explores crucial ontological categories that are designed to classify all existents. The contributors discuss three major categories: substance ontologies, trope ontologies and fact ontologies. In addition, they address the central problems of the theory categories in the classical, phenomenological and analytical tradition.

During the past two decades Metaphysics of Natural Complexes has exerted a strong a growing influence on the continuing development of contemporary philosophy. This new and expanded edition acknowledges this influence and brings together much material. Included are the previously published articles “On the Concept of ‘the World,’” and “Probing the Idea of Nature,” which Buchler wrote subsequent to Metaphysics of Natural Complexes as extensions and completions of the system. Previously unpublished work on the key concept of contour has also been added. In addition there are excerpts from Buchler’s replies to his critics, a set of editors’ notes to facilitate cross-referencing, and an updated index. This work presents a bold and forceful metaphysics and general ontology. It provides a systematic framework for understanding the broadest features of the world and nature, and for locating our understanding of human nature, selfhood, and society as complexes in and of nature. Buchler’s detailed analysis of identity, ordinality, nature, world, and validation advance our understanding of the basic categories to be used in defining and exploring whatever is. Unlike other contemporary philosophers that confine themselves to narrowly defined problems in hermeneutics or theory of knowledge, Buchler is unrelenting in his drive toward a more encompassing perspective, simultaneously combining interpretive precision with sheer breadth of vision.

"Aristotle versus Plato. For a long time that is the angle from which the tale has been told, in textbooks on the history of philosophy and to university students. Aristotle's philosophy, so the story goes, was au fond in opposition to Plato's. But it was not always thus."—from the Introduction In a wide-ranging book likely to cause controversy, Lloyd P. Gerson sets out the case for the "harmony" of Platonism and Aristotelianism, the standard view in late antiquity. He aims to show that the twentieth-century view that Aristotle started out as a Platonist and ended up as an anti-Platonist is seriously flawed. Gerson examines the Neoplatonic commentators on Aristotle based on their principle of harmony. In considering ancient studies of Aristotle's Categories, Physics, De Anima, Metaphysics, and Nicomachean Ethics, the author shows how the principle of harmony allows us to understand numerous texts that otherwise appear intractable. Gerson also explains how these "esoteric" treatises can be seen not to conflict with the early "exoteric" and admittedly Platonic dialogues of Aristotle. Aristotle and Other Platonists concludes with an assessment of some of the philosophical results of acknowledging harmony.

Aristotle's reliance on dialectic as a method of philosophy appears to conflict with his metaphysical realist view of his conclusions. This book explores Aristotle's philosophical method and the merits of his conclusions, and shows how he defends dialectic against the objection that it cannot justify a metaphysical realist's claims. The author does not presuppose extensive previous acquaintance with Aristotle. Greek texts are translated, and Greek words transliterated.